UserAgent.me

What Does Your User Agent Say About You?

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A user agent is a computer program representing a person, for example, a browser in a Web context.

Besides a browser, a user agent could be a bot scraping webpages, a download manager, or another app accessing the Web. Along with each request they make to the server, browsers include a self-identifying User-Agent HTTP header called a user agent (UA) string. This string often identifies the browser, its version number, and its host operating system.

Spam bots, download managers, and some browsers often send a fake UA string to announce themselves as a different client. This is known as user agent spoofing.

The user agent string can be accessed with JavaScript on the client side using the navigator.userAgent property.

A typical user agent string looks like this: "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:35.0) Gecko/20100101 Firefox/35.0".

(Source: Mozilla.org)

User Agent String

Browser Data

Find User Agent In Wireshark Trace

author
James Lee
• Saturday, 31 July, 2021
• 135 min read

When a host is infected or otherwise compromised, security professionals need to quickly review packet captures (caps) of suspicious network traffic to identify affected hosts and users. This tutorial offers tips on how to gather that cap data using Wireshark, the widely used network protocol analysis tool.

agent wireshark user windows host line using chrome users hosts x64 figure google operating microsoft
(Source: unit42.paloaltonetworks.com)

Contents

In most cases, alerts for suspicious activity are based on IP addresses. If you have access to full packet capture of your network traffic, a cap retrieved on an internal IP address should reveal an associated MAC address and hostname.

DHCP traffic can help identify hosts for almost any type of computer connected to your network. Open the cap in Wireshark and filter on boot pas shown in Figure 1.

Note : With Wireshark 3.0, you must use the search term DHCP instead of boot. Select one of the frames that shows DHCP Request in the info column.

Go to the frame details section and expand the line for Bootstrap Protocol (Request) as shown in Figure 2. Expand the lines for Client Identifier and Host Name as indicated in Figure 3.

Figure 3: Finding the MAC address and hostname in a DHCP request This cap is from a Windows host using an internal IP address at 10.2.4101.

agent user wireshark malware pcap strings timestamp specified did location
(Source: pcsxcetrasupport3.wordpress.com)

Figure 5: Correlating hostname with IP and MAC address using Nuns traffic The frame details section also shows the hostname assigned to an IP address as shown in Figure 6.

Figure 7: Following the TCP stream for an HTTP request in the third cap This TCP stream has HTTP request headers as shown in Figure 8.

Figure 11: Following the TCP stream for an HTTP request in the fifth cap However, for those lucky enough to find HTTP web-browsing traffic during their investigation, this method can provide more information about a host.

Go to the frame details section and expand lines as shown in Figure 13. You should find a user account name for Theresa.Johnson in traffic between the domain controller at 172.16.8[.

Figure 14: Finding the Windows user account name Hamstring values for hostnames always end with a $ (dollar sign), while user account names do not.

user wireshark agent using iphone hosts identifying users figure line safari
(Source: unit42.paloaltonetworks.com)

To filter on user account names, use the following Wireshark expression to eliminate Hamstring results with a dollar sign: Using the methods from this tutorial, we can better utilize Wireshark to help us identify affected hosts and users.

Like whether chrome of Firefox or what browser or script is used for connecting to internet services Capturing traffic with pump on Linux CentOS 5.7 machine running Apache HTTP and analyzing in Wireshark.

Making statements based on opinion; back them up with references or personal experience. You can see the FIN, ACK, and RST (reset) packets that are exchanged as part of the standard connection termination.

Using the user ’s secret key derived from the windows' password, a current timestamp is encrypted by the client (Windows workstation or server) and used to populate the Pre-Authentication data with a KRB5-PADATA-ENC-TIMESTAMP message in the request below. This is essentially the exact same message that came through the first time, but now the pre-authentication data is populated.

This includes Message 3 (the TNT from Message 2 and the ID of the requested service, krbtgt@rcbj.net for our Windows Domain login) and Message 4 (Authenticator, encrypted using the Client/TGS Session Key) from our earlier description. At this point, the TGS uses its secret key to decrypt the TNT.

wireshark agent user malware strings pcap specified did location find2
(Source: pcsxcetrasupport3.wordpress.com)

Then, it can retrieve the Client/TGS session key from the decrypted ticket. Then, it can use the session key to decrypt the authenticator (enc-part field).

The TGS can now compare the username in the authenticator to the name in the TNT. If the two names match, TGS proceeds as described below; otherwise, an error will be returned.

Flags: Flags describing what type of Service Ticket to return (in this case, the ticket should be renewable, forwardable, and cannibalized. Etype: The desired encryption algorithm(s) to be used in the response.

To further clarify what secret key is being used to decrypt the Service Ticket in Message 5, recall that every workstation and server registered in the Windows Domain has a computer account defined that has a secret key (password) associated with it. Upon receipt, the client can decrypt the client-server session key that it needs for the next step and the encrypted client-to-server ticket is available for submission to the desired service.

During Windows login for domain users, the final exchange (KRB-AP-REQ and KRB-AP-REP messages) does not actually occur because the “service” we are hitting is the local workstation (or Windows server) login service, which is the same thing that initiated the Kerberos authentication sequence to start with. The first time I ever ran Wireshark to capture the examples used in this post, I spent about ten minutes looking for the third part, that was quite obviously missing.

wireshark strings pcap malware agent user
(Source: pcsxcetrasupport3.wordpress.com)

Hopefully, this also helps anyone to look for an explanation of how Windows domain logins work. Wireshark is the world’s foremost network protocol analyzer, but the rich feature set can be daunting for the unfamiliar.

We hope that you find it useful and look forward to your comments. This book explains all the basic and some advanced features of Wireshark.

As Wireshark has become a very complex program, not every feature may be explained in this book. By reading this book, you will learn how to install Wireshark, how to use the basic elements of the graphical user interface (such as the menu) and what’s behind some advanced features that are not always obvious at first sight.

It will hopefully guide you around some common problems that frequently appear for new (and sometimes even advanced) Wireshark users. Gerald Combs, for initiating the Wireshark project and funding to do this documentation.

Guy Harris, for many helpful hints and a great deal of patience in reviewing this document. Gilbert Ramirez, for general encouragement and helpful hints along the way.

wireshark tcp follow frame contains stream lab window
(Source: gitlearning.wordpress.com)

The authors would also like to thank the following people for their helpful feedback on this document: Pat Tyler, for his suggestions on improving the example on generating a backtrack.

It was originally written in Logbook/XML and converted to Acidic by Gerald Combs. The following table shows the typographic conventions that are used in this guide.

This is a warning should pay attention to a warning, otherwise data loss might occur. This is a noted note will point you to common mistakes and things that might not be obvious.

You could think of a network packet analyzer as a measuring device for examining what’s happening inside a network cable, just like an electrician uses a voltmeter for examining what’s happening inside an electric cable (but at a higher level, of course). Wireshark is available for free, is open source, and is one of the best packet analyzers available today.

Wireshark captures packets and lets you examine their contents. Wireshark can capture traffic from many network media types, including Ethernet, Wireless LAN, Bluetooth, USB, and more.

agent wireshark user hex strings string malware pcap program editor there appears
(Source: pcsxcetrasupport3.wordpress.com)

The specific media types supported may be limited by several factors, including your hardware and operating system. Wireshark is an open source software project, and is released under the GNU General Public License (GPL).

You can freely use Wireshark on any number of computers you like, without worrying about license keys or fees or such. In addition, all source code is freely available under the GPL.

Because of that, it is very easy for people to add new protocols to Wireshark, either as plugins, or built into the source, and they often do! Wireshark isn’t an intrusion detection system.

It will not warn you when someone does strange things on your network that he/she isn’t allowed to do. However, if strange things happen, Wireshark might help you figure out what is really going on.

Wireshark doesn’t send packets on the network or do other active things (except domain name resolution, but that can be disabled). The amount of resources Wireshark needs depends on your environment and on the size of the capture file you are analyzing.

buntstift faber tri winner headers httpclient damian correctly apache eberhard regenbogen trace wireshark request nikodem sent solution thank always edit
(Source: stackoverflow.com)

The values below should be fine for small to medium-sized capture files no more than a few hundred MB. Larger capture files will require more memory and disk space.

A computer with a fast processor, and lots of memory and disk space is always a good idea. Capture files require additional disk space.

It is often difficult or impossible to support these systems due to circumstances beyond our control, such as third party libraries on which we depend or due to necessary features that are only present in newer versions of Windows such as hardened security or memory management. Wireshark 1.10 was the last release branch to officially support Windows XP.

Similar to Windows, supported macOS versions depend on third party libraries and on Apple’s requirements. Wireshark 2.0 was the last release branch to support OS X on 32-bit Intel.

Wireshark 1.8 was the last release branch to support Mac OS X on PowerPC. The system requirements should be comparable to the specifications listed above for Windows.

wireshark agent user pcap malware strings threw error going there
(Source: pcsxcetrasupport3.wordpress.com)

Wireshark runs on most UNIX and UNIX-like platforms including Linux and most BSD variants. The system requirements should be comparable to the specifications listed above for Windows.

Binary packages are available for most UNICEF and Linux distributions including the following platforms: If a binary package is not available for your platform you can download the source and try to build it.

Both are GPG-signed and include verification instructions for Windows, Linux, and macOS. As noted above, you can also verify downloads on Windows and macOS using the code signature validation features on those systems.

In late 1997 Gerald Combs needed a tool for tracking down network problems and wanted to learn more about networking, so he started writing Ethereal (the original name of the Wireshark project) as a way to solve both problems. Ethereal was initially released after several pauses in development in July 1998 as version 0.2.0.

Within days patches, bug reports, and words of encouragement started arriving and Ethereal was on its way to success. Not long after that Gilbert Ramirez saw its potential and contributed a low-level dissector to it.

wireshark adjust string value filter
(Source: samsclass.info)

In October 1998 Guy Harris was looking for something better than tcpview, so he started applying patches and contributing dissectors to Ethereal. In late 1998 Richard Sharpe, who was giving TCP/IP courses, saw its potential on such courses and started looking at it to see if it supported the protocols he needed.

While it didn’t at that point new protocols could be easily added. The list of people who have contributed to the project has become very long since then, and almost all of them started with a protocol that they needed that Wireshark or did not already handle.

So they copied an existing dissector and contributed the code back to the team. In 2006 the project moved house and re-emerged under a new name: Wireshark.

In 2008, after ten years of development, Wireshark finally arrived at version 1.0. This release was the first deemed complete, with the minimum features implemented.

Its release coincided with the first Wireshark Developer and User Conference, called Shark fest. Ongoing development and maintenance of Wireshark is handled by the Wireshark team, a loose group of individuals who fix bugs and provide new functionality.

wireshark filter traffic protocol transfer hypertext information host
(Source: networkproguide.com)

There have also been many people who have contributed protocol dissectors to Wireshark, and it is expected that this will continue. Wireshark is an open source software project, and is released under the GNU General Public License (GPL) version 2.

The developers of Wireshark can further improve your changes or implement additional features on top of your code, which may also benefit you. The maintainers and developers of Wireshark will maintain your code, fixing it when API changes or other changes are made, and generally keeping it in tune with what is happening with Wireshark.

If you have problems or need help with Wireshark there are several places that may be of interest (besides this guide, of course). You will find a lot of information not part of this user ’s guide.

For example, it contains an explanation how to capture on a switched network, an ongoing effort to build a protocol reference, protocol-specific information, and much more. And best of all, if you would like to contribute your knowledge on a specific topic (maybe a network protocol you know well), you can edit the wiki pages with your web browser.

Wireshark .org/ offers a resource where questions and answers come together. You can search for questions asked before and see what answers were given by people who knew about the issue.

wireshark retrieving downloaded
(Source: samsclass.info)

Keep in mind that a lot of people are subscribed to the mailing lists. You might prefer this online version, as it’s typically more up to date and the HTML format is easier to use.

There are several mailing lists of specific Wireshark topics available: Wireshark -announce Information about new program releases, which usually appear about every six weeks.

People typically post questions about using Wireshark and others (hopefully) provide answers. If you want to develop a protocol dissector or update the user interface, join this list.

When reporting problems with Wireshark please supply the following information: The version number of Wireshark and the dependent libraries linked with it, such as Qt or Glib.

Information about the platform you run Wireshark on (Windows, Linux, etc. Don’t send confidential information! If you send capture files to the mailing lists be sure they don’t contain any sensitive or confidential information like passwords or personally identifiable information (Pin).

wireshark tcpdump extract data useful headers webpage capture example website go stack
(Source: stackoverflow.com)

In many cases you can use a tool like TraceWrangler to sanitize a capture file before sharing it. For bugs and feature requests, you can create an issue on Bugzilla and upload the file there.

You can obtain this trace back information with the following commands on UNIX or Linux (note the back ticks): If you do not have GDB available, you will have to check out your operating system’s debugger.

Several Linux distributions offer Wireshark packages, but they commonly provide out-of-date versions. For that reason, you will need to know where to get the latest version of Wireshark and how to install it.

Windows installer names contain the platform and version. The Wireshark installer includes NICAP which is required for packet capture.

/S runs the installer or uninstaller silently with default values. /D sets the default installation directory (Einstein), overriding Install Dir and InstallDirRegKey.

agent malware strings wireshark pcap user found fullsearch
(Source: pcsxcetrasupport3.wordpress.com)

The official Wireshark Windows package will check for new versions and notify you when they are available. If you have the Check for updates preference disabled or if you run Wireshark in an isolated environment you should subscribe to the Wireshark -announce mailing list to be notified of new versions.

A reboot is usually not required and all your personal settings remain unchanged. You can uninstall Wireshark using the Programs and Features control panel.

Select the Wireshark entry to start the uninstallation procedure. The Wireshark uninstaller provides several options for removal.

The default is to remove the core components but keep your personal settings and NICAP. Remember that if you uninstall NICAP you won’t be able to capture anything with Wireshark.

The official macOS packages are distributed as disk images (.DMG) containing the application bundle. In order to capture packets, you must install the “ChmodBPF” launch daemon.

wireshark url
(Source: samsclass.info)

If you are using Linux or your version of UNIX uses GNU tar you can use the following command: Configure your source so it will build correctly for your version of UNIX.

Use the following command to install Wireshark under FreeBSD: A number of errors can occur during the build and installation process.

You can check the file CMakeOutput.log and CMakeError.log in the build directory to find out what failed. Note that installing a library package isn’t enough.

Cmake will also fail if you do not have liberal (at least the required include files) on your system. Include the output from make and anything else you think is relevant such as a trace of the make stage.

By now you have installed Wireshark and are likely keen to get started capturing your first packets. You can start Wireshark from your shell or window manager.

(Source: isc.sans.edu)

In the following chapters a lot of screenshots from Wireshark will be shown. But as there are no real differences in functionality these screenshots should still be well understandable.

Figure 3.1, “The Main window” shows Wireshark as you would usually see it after some packets are captured or loaded (how to do this will be described later). Wireshark ’s main window consists of parts that are commonly known from many other GUI programs.

The main toolbar (see Section 3.16, “The “Main” Toolbar”) provides quick access to frequently used items from the menu. Move to the next packet of the conversation (TCP, UDP or IP).

In the packet detail, opens the selected tree item. In the packet detail, opens the selected tree item and all of its subtrees.

In the packet detail, toggles the selected tree item. Additionally, typing anywhere in the main window will start filling in a display filter.

wireshark decrypt preferences protocols edit log go
(Source: www.python4networkengineers.com)

Lonesome menu items will be disabled (greyed out) if the corresponding feature isn’t available. This menu contains items to open and merge capture files, save, print, or export capture files in whole or in part, and to quit the Wireshark application.

This menu contains items to find a packet, time reference or mark one or more packets, handle configuration profiles, and set your preferences; (cut, copy, and paste are not presently implemented). This menu contains items to manipulate display filters, enable or disable the dissection of protocols, configure user specified decodes and follow a TCP stream.

This menu contains items to display various statistic windows, including a summary of the packets that have been captured, display protocol hierarchy statistics and much more. This menu contains items to display various telephony related statistic windows, including a media analysis, flow diagrams, display protocol hierarchy statistics and much more.

This menu contains items to display Bluetooth and IEEE 802.11 wireless statistics. This menu contains various tools available in Wireshark, such as creating Firewall ACL Rules.

This menu contains items to help the user, e.g. access to some basic help, manual pages of the various command line tools, online access to some webpages, and the usual about dialog. Each of these menu items is described in more detail in the sections that follow.

network
(Source: www.youtube.com)

For example, you can press the Control (or Stag in German) and the K keys together to open the “Capture Options” dialog. Clicking on one of the submenu items will open the corresponding capture file directly.

This menu item brings up the import file dialog box that allows you to import a text file containing a hex dump into a new temporary capture. It is discussed in more detail in Section 5.5, “Import Hex Dump”.

If you haven’t saved the capture, you will be asked to do so first (this can be disabled by a preference setting). If you have not set a default capture file name (perhaps with the -w option), Wireshark pops up the Save Capture File As dialog box (which is discussed further in Section 5.3.1, “The “Save Capture File As” Dialog Box”).

If you have already saved the current capture, this menu item will be greyed out. This menu item allows you to print all (or some) of the packets in the capture file.

This menu item brings up a toolbar that allows you to find a packet by many criteria. This menu item marks all displayed packets as ignored.

wireshark yahoo isa allowed signatures firewall hunt filter 2006 figure25 capture header messenger
(Source: forum.persiannetworks.com)

This menu item set a time reference on the currently selected packet. This menu item removes all time references on the packets.

This menu item tries to find the next time referenced packet. This menu item tries to find the previous time referenced packet.

Opens the “Time Shift” dialog, which allows you to adjust the timestamps of some or all packets. Note that the ability to save packet comments depends on your file format.

Note that the ability to save capture comments depends on your file format. This menu item brings up a dialog box for handling configuration profiles.

This menu item brings up a dialog box that allows you to set preferences for many parameters that control Wireshark. This menu item hides or shows the packet list pane, see.

code wireshark response isa figure31
(Source: www.carbonwind.net)

The fields “Time of Day”, “Date and Time of Day”, “Seconds Since Beginning of Capture”, “Seconds Since Previous Captured Packet” and “Seconds Since Previous Displayed Packet” are mutually exclusive. Selecting this tells Wireshark to display time stamps in seconds, with hours and minutes.

This item allows you to trigger a name resolve of the current packet only, see. This item allows you to control whether Wireshark translates MAC addresses into names, see.

This item allows you to control whether Wireshark translates network addresses into names, see. This item allows you to control whether Wireshark translates transport addresses into names, see.

This item allows you to control whether Wireshark should colorize the packet list. Zoom into the packet data (increase the font size).

Zoom out of the packet data (decrease the font size). Resizing may take a significant amount of time, especially if a large capture file is loaded.

sip avaya digest method response xlite agent user wireshark sm lite challenge phone
(Source: allenluker.wordpress.com)

This menu items folds out with a list of all configured columns. This menu item expands the currently selected subtree in the packet details tree.

This menu item collapses the currently selected subtree in the packet details tree. Wireshark keeps a list of all the protocol subtrees that are expanded, and uses it to ensure that the correct subtrees are expanded when you display a packet.

This menu item expands all subtrees in all packets in the capture. This menu item collapses the tree view of all packets in the capture list.

This makes it easy to distinguish packets belonging to different conversations. These menu items enable one of the ten temporary color filters based on the currently selected conversation.

This menu item clears all temporary coloring rules. This menu item opens a dialog window in which a new permanent coloring rule can be created based on the currently selected conversation.

fingerprints wii nintendo there
(Source: kontrolissues.net)

This menu item brings up a dialog box that allows you to color packets in the packet list pane according to filter expressions you choose. This menu item allows you to reload the current capture file.

Menu ItemDescriptionShows the tuples (address and port combinations) used to identify each conversation. Go to the corresponding packet of the currently selected protocol field.

If the selected field doesn’t correspond to a packet, this item is greyed out. Menu ItemAcceleratorDescriptionImmediately starts capturing packets with the same settings as the last time.

Stops the currently running capture and starts it again with the same options. Menu ItemAcceleratorDescriptionShows a dialog box that allows you to create and edit display filter macros.

Change the current display filter and apply it immediately. Depending on the chosen menu item, the current display filter string will be replaced or appended to by the selected protocol field in the packet details pane.

(Source: isc.sans.edu)

Change the current display filter but won’t apply it. Depending on the chosen menu item, the current display filter string will be replaced or appended to by the selected protocol field in the packet details pane.

Open a window showing expert information found in the capture. Some protocol dissectors add packet detail items for notable or unusual behavior, such as invalid checksums or retransmissions.

Each menu item brings up a new window showing specific statistics. Each menu item shows specific telephony related statistics.

Each menu item shows specific Bluetooth and IEEE 802.11 statistics. Menu ItemAcceleratorDescriptionThis allows you to create command-line ACL rules for many firewall products, including Cisco IOS, Linux Net filter (iptables), OpenBSD pf and Windows Firewall (via nets).

This allows you to extract credentials from the current capture file. This menu item starts a Web browser showing one of the locally installed HTML manual pages.

(Source: social.msdn.microsoft.com)

Reopening a Web browser might be unsupported in your version of Wireshark. The main toolbar provides quick access to frequently used items from the menu.

This toolbar cannot be customized by the user, but it can be hidden using the View menu if the space on the screen is needed to show more packet data. For example, in the image below shows the main window toolbar after a file has been opened.

Hold down the Alt key (Option on macOS) to go back in the selection history. Hold down the Alt key (Option on macOS) to go forward in the selection history.

After you’ve changed something in this field, don’t forget to press the Apply button (or the Enter/Return key), to apply this filter string to the display. Reset the current display filter and clear the edit area.

Apply the current value in the edit area as the new display filter. Applying a display filter on large capture files might take quite a long time.

The example shows a filter button with the label “Squirrels”. If you have lots of buttons you can arrange them into groups by using “//” as a label separator.

While dissecting a packet, Wireshark will place information from the protocol dissectors into the columns. For example, in the image above the first packet is selected, which is a DNS request.

Wireshark treats them as belonging to the same conversation and draws a line connecting them. The protocols and fields of the packet shown in a tree which can be expanded and collapsed.

Wireshark itself will generate additional protocol information which isn’t present in the captured data. In this case you can see each data source by clicking its corresponding tab at the bottom of the pane.

The context menu (right mouse click) of the tab labels will show a list of all available pages. This can be helpful if the size in the pane is too small for all the tab labels.

Drag the handles between the text areas to change the size. This status bar is shown while no capture file is loaded, e.g. when Wireshark is started.

The colorized bullet… on the left shows the highest expert information level found in the currently loaded capture file. Hovering the mouse over this icon will show a description of the expert info level, and clicking the icon will bring up the Expert Information dialog box.

The edit icon… on the left side lets you add a comment to the capture file using the Capture File Properties dialog. The left side… shows the capture file name by default.

It also shows field information when hovering over and selecting items in the packet detail and packet bytes panes, as well as general notifications. The middle… shows the current number of packets in the capture file.

Clicking on this part of the status bar will bring up a menu with all available configuration profiles, and selecting from this list will change the configuration profile. This is displayed if you have selected a protocol field in the “Packet Details” pane.

Tithe value between the parentheses (in this example “ipv6.src”) is the display filter field for the selected item. You can become more familiar with display filter fields by selecting different packet detail items.

Capture from different kinds of network hardware such as Ethernet or 802.11. Simultaneously show decoded packets while Wireshark is capturing.

Filter packets, reducing the amount of data to be captured. Save packets in multiple files while doing a long term capture, optionally rotating through a fixed number of files (a “ring buffer”).

You may need special privileges to start a live capture. You need to choose the right network interface to capture packet data from.

Some interfaces allow or require configuration prior to capture. This will be indicated by a configuration icon () to the left of the interface name.

Clicking on the icon will show the configuration dialog for that interface. Hovering over an interface will show any associated IPv4 and IPv6 addresses and its capture filter.

When you select (or use the corresponding item in the main toolbar), Wireshark pops up the “Capture Options” dialog box as shown in Figure 4.3, “The “Capture Options” input tab”. If you are unsure which options to choose in this dialog box, leaving the defaults settings as they are should work well in many cases.

The “Input” tab contains the “Interface” table, which shows the following columns: Traffic A sparkling showing network activity over time.

Naples The snapshot length, or the number of bytes to capture for each packet. You can set an explicit length if needed, e.g. for performance or privacy reasons.

You can increase or decrease this as needed, but the default is usually sufficient. Monitor Mode Lets you capture full, raw 802.11 headers.

Support depends on the interface type, hardware, driver, and OS. Note that enabling this might disconnect you from your wireless network.

The “Output” tab shows the following information: If left blank, the capture data will be stored in a temporary file.

A new capture file can be created based on the following conditions: Display Options Update list of packets in real-time Updates the packet list pane in real time during capture.

If you do not enable this, Wireshark will not display any packets until you stop the capture. This option is greyed out if “Update list of packets in real-time” is disabled.

Click + and type the name of the pipe including its path. To remove a pipe from the list of interfaces, select it and press -.

The Remote Packet Capture Protocol service must first be running on the target platform before Wireshark can connect to it. On Linux or Unix you can capture (and do so more securely) through an SSH tunnel.

To add a new remote capture interface, click + and specify the following: Host The IP address or host name of the target platform where the Remote Packet Capture Protocol service is listening.

The drop down list contains the hosts that have previously been successfully contacted. Password authentication Lets you specify the username and password required to connect to the Remote Packet Capture Protocol service.

In contrast to the local interfaces they are not saved in the preferences file. This is the default port used by the Remote Packet Capture Protocol service.

The “Compiled Filter Output” dialog box The results of compiling a filter for the selected interface are shown on the right.

While capturing the underlying liberal capturing engine will grab the packets from the network card and keep the packet data in a (relatively) small kernel buffer. This data is read by Wireshark and saved into a capture file.

By default, Wireshark saves packets to a temporary file. You can also tell Wireshark to save to a specific (“permanent”) file and switch to a different file after a given time has elapsed or a given number of packets have been captured.

Working with large files (several hundred MB) can be quite slow. This will spread the captured packets over several smaller files which can be much more pleasant to work with.

Using the “Multiple files” option may cut context related information. Wireshark keeps context information of the loaded packet data, so it can report context related problems (like a stream error) and keeps information about context related protocols (e.g. where data is exchanged at the establishing phase and only referred to in later packets).

File Name“Create a new file…”“Use a ring buffer…” ModeResulting filename(s) usedwiresharkXXXXXX (where XXX XXX is a unique number) After capturing is stopped this file can be saved later under a user specified name.

If you want to place the new capture file in a specific folder choose this mode. This mode will limit the maximum disk usage, even for an unlimited amount of capture input data, only keeping the latest captured data.

In most cases you won’t have to modify link-layer header type. If you are capturing traffic from a Cisco Cable Modem Termination System that is putting DO CSIS traffic onto the Ethernet to be captured, select “DO CSIS”, otherwise select “Ethernet”.

If you are capturing on an 802.11 device on some versions of BSD you might be offered a choice of “Ethernet” or “802.11”. Unless the capture needs to be read by an application that doesn’t support 802.11 headers you should select “802.11”.

If you are capturing on an En dace DAG card connected to a synchronous serial line you might be offered a choice of “PPP over serial” or “Cisco HDLC”. If you are capturing on an En dace DAG card connected to an ATM network you might be offered a choice of “RFC 1483 IP-over-ATM” or “Sun raw ATM”.

You can optionally precede the primitive with the keyword src|DST to specify that you are only interested in source or destination addresses. You can optionally precede this primitive with the keyword src|DST to specify that you are only interested in a source or destination network.

If neither of these are present, packets will be selected that have the specified network in either the source or destination address. In addition, you can specify either the net mask or the CDR prefix for the network if they are different from your own.

You can optionally precede this primitive with the keywords' src|DST and TCP|UDP which allow you to specify that you are only interested in source or destination ports and TCP or UDP packets respectively. If these are not specified, packets will be selected for both the TCP and UDP protocols and when the specified address appears in either the source or destination port field.

Ether|IP broadcast|multicast This primitive allows you to filter on either Ethernet or IP broadcasts or multicasts. rel op This primitive allows you to create complex filter expressions that select bytes or ranges of bytes in packets.

To avoid this, Wireshark tries to figure out if it’s remotely connected (by looking at some specific environment variables) and automatically creates a capture filter that matches aspects of the connection. On Windows it asks the operating system if it’s running in a Remote Desktop Services environment.

You might see the following dialog box while a capture is running: This dialog box shows a list of protocols and their activity over time.

A running capture session will be stopped in one of the following ways: This chapter will describe input and output of capture data.

You can use drag and drop to open Wilson most systems you can open a file by simply dragging it in your file manager and dropping it onto Wireshark ’s main window. If you haven’t previously saved the current capture file you will be asked to do so to prevent data loss.

In addition to its native file format (pacing), Wireshark can read and write capture files from many other packet capture programs as well. The following sections show some examples of the Wireshark “Open File” dialog box.

Click the Cancel button to go back to Wireshark and not load a capture file. The Help button will take you to this section of the User ’s Guide”.

The text field background will turn green for a valid filter string and red for an invalid one. Read filters can be used to exclude various types of traffic, which can be useful for large capture files.

This is the common Windows file open dialog along with some Wireshark extensions. This is the common Qt file open dialog along with some Wireshark extensions.

The following file formats from other capture tools can be opened by Wireshark : A flexible, extensible successor to the liberal format.

It may not be possible to read some formats dependent on the packet types captured. Ethernet captures are usually supported for most file formats but it may not be possible to read other packet types such as PPP or IEEE 802.11 from all file formats.

For example, most file formats don’t record the number of dropped packets. This is the common Windows file save dialog with some additional Wireshark extensions.

This is the common Qt file save dialog with additional Wireshark extensions. Type in the name of the file in which you wish to save the captured packets.

You can choose from the types described in Section 5.3.2, “Output File Formats”. The Help button will take you to this section of the User ’s Guide”.

Click on the Cancel button to go back to Wireshark without saving any packets. Wireshark can convert file formation can convert capture files from one format to another by opening a capture and saving it as a different format.

Wireshark can save the packet data in its native file format (pacing) and in the file formats of other protocol analyzers so other tools can read the capture data. Saving in a different format might lose damasking your file in a different format might lose information such as comments, name resolution, and time stamp resolution.

Third party protocol analyzers may require specific file extensions Wireshark examines a file’s contents to determine its type. Some other protocol analyzers only look at a filename extensions.

For example, you might need to use the .cap extension in order to open a file using Sniffer. See Section 5.4.1, “The “Merge With Capture File” Dialog Box” for details.

This menu item will be disabled unless you have loaded a capture file. If you drop a single file it will simply replace the existing capture.

Use the merge cap tool from the command line to merge capture files. This tool provides the most options to merge capture files.

See Section D.8, merge cap : Merging multiple capture files into one” for details. This is the common Windows file open dialog with additional Wireshark extensions.

This is the Qt file open dialog with additional Wireshark extensions. Wireshark can read in an ASCII hex dump and write the data described into a temporary liberal capture file.

It is also capable of generating dummy Ethernet, IP and UDP, TCP, or SMTP headers, in order to build fully processable packet dumps from hex dumps of application-level data only. Wireshark understands a hex dump of the form generated by OD -Ax -tx1 -v.

In other words, each byte is individually displayed and surrounded with a space. Byte and hex numbers can be uppercase or lowercase.

Any text before the offset is ignored, including email forwarding characters >. An offset is recognized as being a hex number longer than two characters.

If not the first packet is timestamped with the current time the import takes place. Multiple packets are written with timestamps differing by one microsecond each.

In general, short of these restrictions, Wireshark is pretty liberal about reading in hex dumps and has been tested with a variety of mangled outputs (including being forwarded through email multiple times, with limited line wrap etc.) Any line beginning with #TEXT2PCAP is a directive and options can be inserted after this command to be processed by Wireshark.

In the future these may be used to give more fine-grained control on the dump and the way it should be processed e.g. timestamps, encapsulation type etc. Wireshark also allows the user to read in dumps of application-level data, by inserting dummy L2, L3 and L4 headers before each packet.

Filename / Browse Enter the name of the text file to import. This is usually hexadecimal, but decimal and octal are also supported.

It uses a simple syntax to describe the format of the timestamps, using oh for hours, km for minutes, is for seconds, etc. The straightforward HH:MM:SS format is covered by at.

If there are no timestamps in the text file to import leave this field empty and timestamps will be generated based on the time of import. These are on a separate line before each frame and start with either I or i for input and O or o for output.

It lists all types that Wireshark understands, to pass the capture file contents to the right dissector. These headers can provide artificial Ethernet, IP, UDP, TCP or SMTP headers or SMTP data chunks.

When selecting a type of dummy header the applicable entries are enabled, others are grayed out and default values are used. When the Wireshark Upper PDU export encapsulation is selected the option Export PDU becomes available.

This allows you to enter the name of the dissector these frames are to be directed to. Here you can define how much data from the start of the frame you want to import.

The content of this dialog box is updated each time a capture file is opened/closed. Wireshark provides a variety of options for exporting packet data.

This section describes general ways to export data from the main Wireshark application. There are many other ways to export or extract data from capture files, including processing shark output and customizing Wireshark and shark using LA scripts.

This can be useful for trimming irrelevant or unwanted packets from a capture file. Some controls are unavailable for some formats, notably CSV and JSON.

Tip you would like to be able to import any previously exported packets from a plain text file it is recommended that you do the following: Disable the “Show not dissected data on new Packet Bytes pane” preference.

This feature scans through the selected protocol’s streams in the currently open capture file or running capture and allows the user to export reassembled objects to the disk. If you have a capture running, this list is automatically updated every few seconds with any new objects seen.

The saved objects can then be opened or examined independently of Wireshark. For example, HTTP uses the final part of the URI and IMF uses the subject of the email.

Wireshark will display the “Print” dialog box as shown below. It’s easy to waste paper doing misprinted output can contain lots of text, particularly if you print packet details and bytes.

See Section 5.9, “The “Packet Range” Frame” for details. The packet range frame is a part of the “,” “,” and Print dialog boxes.

The packet format frame is also a part of the “” and Print dialog boxes. For example, when exporting to a text file this will put a form feed character between each packet.

You can then expand any part of the tree to view detailed information about each protocol in each packet. You can also select and view packets the same way while Wireshark is capturing if you selected “Update list of packets in real time” in the “Capture Preferences” dialog box.

In addition, you can view individual packets in a separate window as shown in Figure 6.2, “Viewing a packet in a separate window”. This allows you to easily compare two or more packets, even across multiple files.

The following table gives an overview of which functions are available in this header, where to find the corresponding function in the main menu, and a description of each item. Remove this column, similar to deleting it in the “Preferences” dialog.

The following table gives an overview of which functions are available in this pane, where to find the corresponding function in the main menu, and a short description of each item. ItemCorresponding main menu itemDescriptionIgnore or inspect this packet while dissecting the capture file.

Opens the “Time Shift” dialog, which allows you to adjust the timestamps of some or all packets. Note that the ability to save packet comments depends on your file format.

Allows you to enter a name to resolve for the selected address. Immediately replace or append the current display filter based on the most recent packet list or packet details item selected.

Change the current display filter based on the most recent packet list or packet details item selected, but don’t apply it. Apply a display filter with the address information from the selected packet.

Create a new colorizing rule based on address information from the selected packet. Allows you to analyze and prepare a filter for this SMTP association.

See the wiki page on SSL for instructions on providing TLS keys. Copy the summary fields as displayed to the clipboard as tab-separated text.

Copy the summary fields as displayed to the clipboard as comma-separated text. Copy the summary fields as displayed to the clipboard as YAML data.

Copy the packet bytes to the clipboard in full “hex dump” format. Copy the packet bytes to the clipboard in “hex dump” format without the ASCII portion.

Copy the packet bytes to the clipboard as ASCII text, excluding non-printable characters. Copy the packet bytes to the clipboard as an punctuated list of hex digits.

Copy the packet bytes to the clipboard as raw binary. The following table gives an overview of which functions are available in this pane, where to find the corresponding function in the main menu, and a short description of each item.

ItemCorresponding main menu itemDescriptionExpand the currently selected subtree. Wireshark keeps a list of all the protocol subtrees that are expanded, and uses it to ensure that the correct subtrees are expanded when you display a packet.

This menu item collapses the tree view of all packets in the capture list. Use the selected protocol item to create a new column in the packet list.

Immediately replace or append the current display filter based on the most recent packet list or packet details item selected. Change the current display filter based on the most recent packet list or packet details item selected, but don’t apply it.

See the wiki page on SSL for instructions on providing TLS keys. Copy the selected packet detail and its children as displayed.

Copy the displayed text of the selected field to the system clipboard. Copy the name of the selected field to the system clipboard.

Copy the value of the selected field to the system clipboard. Prepare a display filter based on the currently selected item and copy it to the clipboard.

Copy the packet bytes to the clipboard in full “hex dump” format. Copy the packet bytes to the clipboard in “hex dump” format without the ASCII portion.

Copy the packet bytes to the clipboard as ASCII text, excluding non-printable characters. Copy the packet bytes to the clipboard as an punctuated list of hex digits.

Copy the packet bytes to the clipboard as raw binary. Copy the packet bytes to the clipboard as C-style escape sequences.

It allows you to export raw packet bytes to a binary file. Show the wiki page corresponding to the currently selected protocol in your web browser.

If the selected field has a corresponding packet such as the matching request for a DNS response, go to it. The following table gives an overview of which functions are available in this pane along with a short description of each item.

ItemDescriptionCopy the packet bytes to the clipboard in full “hex dump” format. Copy the packet bytes to the clipboard in “hex dump” format without the ASCII portion.

Copy the packet bytes to the clipboard as ASCII text, excluding non-printable characters. Copy the packet bytes to the clipboard as an punctuated list of hex digits.

Copy the packet bytes to the clipboard as raw binary. Copy the packet bytes to the clipboard as C-style escape sequences.

Use EBCDIC encoding when displaying “hex dump” text. Display filters allow you to concentrate on the packets you are interested in while hiding the currently uninteresting ones.

To only display packets containing a particular protocol, type the protocol name in the display filter toolbar of the Wireshark window and press enter to apply the filter. Figure 6.7, “Filtering on the TCP protocol” shows an example of what happens when you type TCP in the display filter toolbar.

Note Don’t forget to press enter or click on the apply display filter button after entering the filter expression. Stephen using a display filter, all packets remain in the capture file.

More information about the Display Filter Expression dialog box is available in. These comparisons can be combined with logical operators, like “and” and “or”, and parentheses into complex expressions.

The following sections will go into the display filter functionality in more detail. A full list of the available protocols and fields is available through the menu item .

You can build display filters that compare values using a number of different comparison operators. Tip English and C-like operators are interchangeable and can be mixed within a filter string.

Protocol or text field matches a Perl-compatible regular expression A Boolean field is present whether its value is true or false.

To only match TCP packets with the SYN flag set, you need to use TCP.flags.syn == 1. Ethernet address 6 bytes separated by a colon (:), dot (.

For example, this display filter will find all packets in the 129.111 Class-B network: The display filter above matches packets that contains the 3-byte sequence 0×81, 0×60, 0×03 anywhere in the UDP header or payload.

The display filter above matches packets where the SIP To-header contains the string “a1762” anywhere in the header. The display filter above matches HTTP packets where the HOST header contains acme.org, acme.com, or acme.net.

Wireshark allows you to select a subsequence of a sequence in rather elaborate ways. After a label you can place a pair of brackets containing a comma separated list of range specifiers.

In this case n is the beginning offset and m is the length of the range being specified. The example above uses the :m format, which takes everything from the beginning of a sequence to offset m. It is equivalent to 0:m.

The example above uses the n: format, which takes everything from offset n to the end of the sequence. After the field name, use the in operator followed by the set items surrounded by braces {}.

For example, to display packets with a TCP source or destination port of 80, 443, or 8080, you can use TCP.port in {80 443 8080}. In contrast, the membership operator tests a single field against the range condition.

Returns the number of field occurrences in a frame. Note that the Len function yields the string length in bytes rather than (multi-byte) characters.

People often use a filter string like IP.add == 1.2.3.4 to display all packets containing the IP address 1.2.3.4. Then they use IP.add != 1.2.3.4 expecting to see all packets not containing the IP address 1.2.3.4 in it.

Instead, that expression will even be true for packets where either the source or destination IP address equals 1.2.3.4. The reason for this is that the expression IP.add != 1.2.3.4 is read as “the packet contains a field name dip.add with a value different from 1.2.3.4”.

(IP.add == 1.2.3.4) as it is read “show me all the packets for which it is not true that a field name dip.add exists with a value of 1.2.3.4”, or in other words, “filter out all packets for which there are no occurrences of a field name dip.add with the value 1.2.3.4”. As protocols evolve they sometimes change names or are superseded by newer standards.

If a protocol dissector originally used the older names and fields for a protocol the Wireshark development team might update it to use the newer names and fields. In such cases they will add an alias from the old protocol name to the new one in order to make the transition easier.

For example, the DHCP dissector was originally developed for the Boot protocol but as of Wireshark 3.0 all the “boot” display filter fields have been renamed to their “DHCP” equivalents. You can still use the old filter names for the time being, e.g. “boot.type” is equivalent to “DHCP.type” but Wireshark will show the warning “”boot” is deprecated” when you use it.

However, if you are new to Wireshark or are working with a slightly unfamiliar protocol it can be very confusing to try to figure out what to type. The “Display Filter Expression” dialog box helps with this.

Tithe “Display Filter Expression” dialog box is an excellent way to learn how to write Wireshark display filter strings. When you first bring up the Display Filter Expression dialog box you are shown a tree of field names, organized by protocol, and a box for selecting a relation.

Every protocol with filterable fields is listed at the top level. When you select a field from the field name list and select a binary relation (such as the equality relation ==) you will be given the opportunity to enter a value, and possibly some range information.

This can save time in remembering and retyping some of the more complex filters you use. Wireshark will open the corresponding dialog as shown in Figure 6.9, “The “Capture Filters” and “Display Filters” dialog boxes”.

To add a new filter macro, click the + button in the bottom-left corner. A new row will appear in the Display Filter Macros table above.

To save your modifications, click the OK button in the bottom-right corner of the Figure 6.10, “Display Filter Macros window”. Display filter Enter a display filter string into the text entry field and click the Find button.

+ For example, to find the three-way handshake for a connection from host 192.168.0.1, use the following filter string: The value to be found will be syntax checked while you type it in.

Hexadecimal Value Search for a specific byte sequence in the packet data. Pure patterns are beyond the scope of this document, but typing “pure test” into your favorite search engine should return a number of sites that will help you test and explore your expressions.

This toolbar can be opened by selecting from the main menu. A marked packet will be shown with black background, regardless of the coloring rules set.

Marking a packet can be useful to find it later while analyzing in a large capture file. Marked packet information is not stored in the capture file or anywhere else.

An ignored packet will be shown with white background and gray foreground, regardless of the coloring rules set. Ignored packet information is not stored in the capture file or anywhere else.

The absolute date and time of the day when the packet was captured. The time relative to epoch (midnight UTC of January 1, 1970).

The timestamp precision of the loaded capture file format will be used (the default). If the precision is larger, the remaining decimal places will be cut off.

Precision example: If you have a timestamp and it’s displayed using, “Seconds Since Previous Packet” the value might be 1.123456. This will be displayed using the “Automatic” setting for liberal files (which is microseconds).

It will be useful, if you want to see the time values relative to a special packet, e.g. the start of a new request. It’s possible to set multiple time references in the capture file.

The time references will not be saved permanently and will be lost when you close the capture file. Toggles the time reference state of the currently selected packet to on or off.

Maybe you just need a display filter to show only the packets in a TLS or SSL stream. Wireshark will set an appropriate display filter and display a dialog box with the data from the stream laid out, as shown in Figure 7.1, “The “Follow TCP Stream” dialog box”.

Closing the dialog with the “Back” button will reset the display filter if this behavior is not desired. The stream content is displayed in the same sequence as it appeared on the network.

These colors can be changed by opening and under , selecting different colors for the Sample “Follow Stream” client text and Sample “Follow Stream” server text options. The stream content won’t be updated while doing a live capture.

To get the latest content you’ll have to reopen the dialog. Back Close this dialog box and restore the previous display filter.

By default, Wireshark displays both client and server data. This will require a lot of screen space and is best used with binary protocols.

This allows you to load the unaltered stream data into a different program for further examination. The display will look the same as the ASCII setting, but “Save As” will result in a binary file.

The Quick protocol is similar, the first number selects the UDP stream index while the “Sub stream” field selects the Quick Stream ID. If a selected packet field does not show all the bytes (i.e. they are truncated when displayed) or if they are shown as bytes rather than string or if they require more formatting because they contain an image or HTML then this dialog can be used.

All control characters and non-ASCII bytes are replaced by dot. In this view all control characters are shown using a UTF-8 symbol and all non-ASCII bytes are replaced by dot.

This will require a lot of screen space and is best used with binary protocols. This allows you to see all the data formatted as an HTML document.

Most popular formats are supported including PNG, JPEG, GIF, and BMP. This allows you to load the unaltered stream data into a different program for further examination.

The display will show HEX data, but “Save As” will result in a binary file. Wireshark keeps track of any anomalies and other items of interest it finds in a capture file and shows them in the Expert Information dialog.

The goal is to give you a better idea of uncommon or notable network behavior and to let novice and expert users find network problems faster than manually scanning through the packet list. Every network is different, and it’s up to you to verify that Wireshark ’s expert information applies to your particular situation.

The presence of expert information doesn’t necessarily indicate a problem and absence of expert information doesn’t necessarily mean everything is OK. The amount of expert information largely depends on the protocol being used.

Expert information entries are grouped by severity level (described below) and contain the following: Every expert information item has a severity level.

Wireshark marks them using different colors, which are shown in parentheses: Chat (blue) Information about usual workflow, e.g. a TCP packet with the SYN flag set.

Note (cyan) Notable events, e.g. an application returned a common error code such as HTTP 404. Short explanatory text for each expert information item.

Along with severity levels, expert information items are categorized by group. Assumption The protocol field has incomplete data and was dissected based on assumed value.

Undecided Dissection incomplete or data can’t be decoded for other reasons. The protocol dissector that created the expert information item.

Limit to display filter Only show expert information items present in packets that match the current display filter. For example, you can deselect Chat and Note securities if desired.

The packet detail tree marks fields with expert information based on their severity level color, e.g. “Warning” securities have a yellow background. This color is propagated to the top-level protocol item in the tree in order to make it easy to find the field that created the expert information.

For the example screenshot above, the IP “Time to live” value is very low (only 1), so the corresponding protocol field is marked with a cyan background. An optional “Expert Info Severity” packet list column is available that displays the most significant severity of a packet or stays empty if everything seems OK.

By default, Wireshark ’s TCP dissector tracks the state of each TCP session and provides additional information when problems or potential problems are detected. Analysis is done once for each TCP packet when a capture file is first opened.

Set when there are no analysis flags and for zero window probes. This is initially zero and calculated based on the previous packet in the same TCP flow.

Set when there are no analysis flags and for zero window probes. TCP Asked unseen segment Set when the expected next acknowledgment number is set for the reverse direction and it’s less than the current acknowledgment number.

In the forward direction, the segment size is greater than zero or the SYN or FIN is set. TCP Keep-Alive Set when the segment size is zero or one, the current sequence number is one byte less than the next expected sequence number, and any of SYN, FIN, or RST are set.

TCP Keep-Alive ACK Set when all the following are true: In the forward direction, the segment length is greater than zero or the SYN or FIN is set.

TCP Port numbers reused Set when the SYN flag is set (not SYN+ACK), we have an existing conversation using the same addresses and ports, and the sequence number is different from the existing conversation’s initial sequence number. TCP Previous segment not captured Set when the current sequence number is greater than the next expected sequence number.

TCP Retransmission Set when all the following are true: In the forward direction, the segment length is greater than zero or the SYN or FIN flag is set.

TCP Window Update Set when the all the following are true: The window field in each TCP header advertises the amount of data a receiver can accept.

However, in most cases this indicates a performance or capacity problem on the receiving end. It might take a long time (sometimes several minutes) to resume a paused connection, even if the underlying condition that caused the zero window clears up quickly.

TCP ZeroWindowProbe Set when the sequence number is equal to the next expected sequence number, the segment size is one, and last-seen window size in the reverse direction was zero. If the single data byte from a Zero Window Probe is dropped by the receiver (not Asked), then a subsequent segment should not be flagged as retransmission if all the following conditions are true for that segment: * The segment size is larger than one.

The last-seen packet in the reverse direction was a zero window probe. TCP Conversation Completeness TCP conversations are said to be complete when they have both opening and closing handshakes, independently of any data transfer.

Time stamps, their precision and all that can be quite confusing. This section will provide you with information about what’s going on while Wireshark processes time stamps.

These time stamps will be saved to the capture file, so they also will be available for (later) analysis. While capturing, Wireshark gets the time stamps from the liberal (NICAP) library, which in turn gets them from the operating system kernel.

The internal format that Wireshark uses to keep a packet time stamp consists of the date (in days since 1.1.1970) and the time of day (in nanoseconds since midnight). You can adjust the way Wireshark displays the time stamp data in the packet list, see the “Time Display Format” item in the Section 3.7, “The “View” Menu” for details.

While reading or writing capture files, Wireshark converts the time stamp data between the capture file format and the internal format as required. Unless you are working with specialized capturing hardware, this resolution should be adequate.

Every capture file format that Wireshark knows supports time stamps. The time stamp precision supported by a specific capture file format differs widely and varies from one second “0” to one nanosecond “0.123456789”.

Most file formats store the time stamps with a fixed precision (e.g. microseconds), while some file formats are even capable of storing the time stamp precision itself (whatever the benefit may be). The common liberal capture file format that is used by Wireshark (and a lot of other tools) supports a fixed microsecond resolution “0.123456” only.

Writing data into a capture file format that doesn’t provide the capability to store the actual precision will lead to loss of information. For example, if you load a capture file with nanosecond resolution and store the capture data in a liberal file (with microsecond resolution) Wireshark obviously must reduce the precision from nanosecond to microsecond.

People often ask “Which time stamp accuracy is provided by Wireshark ?”. Well, Wireshark doesn’t create any time stamps itself but simply gets them from “somewhere else” and displays them.

Note USB connected network adapters often provide a very bad time stamp accuracy. The incoming packets have to take “a long and winding road” to travel through the USB cable until they actually reach the kernel.

Many organizations simply set the time zone on their servers and networking gear to UTC in order to make coordination and troubleshooting easier. Tip you travel around the world, it’s an often made mistake to adjust the hours of your computer clock to the local time.

Don’t adjust the hours but your time zone setting instead! You can use the Network Time Protocol (NTP) to automatically adjust your computer to the correct time, by synchronizing it to Internet NTP clock servers.

NTP clients are available for all operating systems that Wireshark supports (and for a lot more), for examples see http://www.ntp.org/. When capturing, NICAP has to convert the time to UTC before supplying it to Wireshark.

Other capture file formats, such as the Microsoft Network Monitor, DOS-based Sniffer, and Network Instruments Observer formats, save the arrival time of packets as local time values. Internally to Wireshark, time stamps are represented in UTC.

For example let’s assume that someone in Los Angeles captured a packet with Wireshark at exactly 2 o’clock local time and sends you this capture file. The capture file’s time stamp will be represented in UTC at 10 o’clock.

You are located in Berlin and will see 11 o’clock on your Wireshark display. Now you have a phone call, video conference or Internet meeting with that one to talk about that capture file.

As you are both looking at the displayed time on your local computers, the one in Los Angeles still sees 2 o’clock but you in Berlin will see 11 o’clock. Conclusion : You may not bother about the date/time of the time stamp you currently look at unless you must make sure that the date/time is as expected.

Network protocols often need to transport large chunks of data which are complete in themselves, e.g. when transferring a file. The underlying protocol might not be able to handle that chunk size (e.g. limitation of the network packet size), or is stream-based like TCP, which doesn’t know data chunks at all.

In that case the network protocol has to handle the chunk boundaries itself and (if required) spread the data over multiple packets. It obviously also needs a mechanism to determine the chunk boundaries on the receiving side.

For some network protocols Wireshark knows of, a mechanism is implemented to find, decode and display these chunks of data. Wireshark will try to find the corresponding packets of this chunk, and will show the combined data as additional pages in the “Packet Bytes” pane (for information about this pane.

Reassembly might take place at several protocol layers, so it’s possible that multiple tabs in the “Packet Bytes” pane appear. Noted will find the reassembled data in the last packet of the chunk.

For example, in an HTTP GET response, the requested data (e.g. an HTML page) is returned. Wireshark will show the hex dump of the data in a new tab “Uncompressed entity body” in the “Packet Bytes” pane.

Enabling or disabling reassembly settings for a protocol typically requires two things: The lower level protocol (e.g., TCP) must support reassembly.

Protocols such as HTTP or TLS are likely to span multiple TCP segments. The TCP protocol preference “Allow subdissector to reassemble TCP streams” (enabled by default) makes it possible for Wireshark to collect a contiguous sequence of TCP segments and hand them over to the higher level protocol (for example, to reconstruct a full HTTP message).

Disable this preference to reduce memory and processing overhead if you are only interested in TCP sequence number analysis (Section 7.5, “TCP Analysis”). Keep in mind, though, that higher level protocols might be wrongly dissected.

To reassemble of out-of-order TCP segments, the TCP protocol preference “Reassemble out-of-order segments” (currently disabled by default) must be enabled in addition to the previous preference. Otherwise, (if missing segments are encountered while sequentially processing a packet capture), it is assumes that the new and missing segments belong to the same PDU.

Applications usually retransmit segments until these are acknowledged, but if the packet capture drops packets, then Wireshark will not be able to reconstruct the TCP stream. In such cases, you can try to disable this preference and hopefully have a partial dissection instead of seeing just “” for every TCP segment.

When doing a capture in monitor mode (IEEE 802.11), packets are more likely to get lost due to signal reception issues. For example, assume six segments forming two Plus ABC and DEF.

In the GUI and during a two-pass dissection (shark -2), the previous scenario will display both Plus in the packet with last segment (F) rather than displaying it in the first packet that has the final missing segment of a PDU. If the previous scenario however occurs, then the time of the request is based on the frame where all missing segments are received.

Regardless of the setting of these two reassembly-related preferences, you can always use the “Follow TCP Stream” option (Section 7.2, “Following Protocol Streams”) which displays segments in the expected order. Name resolution tries to convert some numerical address values into a human-readable format.

There are two possible ways to do these conversions, depending on the resolution to be done: calling system/network services (like the hostname() function) and/or resolve from Wireshark specific configuration files. The name resolution feature can be enabled individually for the protocol layers listed in the following sections.

The resolved names might not be available if you open the capture file later or on a different machine. As a result, each time you or someone else opens a particular capture file it may look slightly different due to changing environments.

DNS may add additional packets to your capture file. You might run into the observer effect if the extra traffic from Wireshark ’s DNS queries and responses affects the problem you’re trying to troubleshoot or any subsequent analysis.

The same sort of thing can happen when capturing over a remote connection, e.g. SSH or RDP. However, if the name resolution information should change while Wireshark is running, Wireshark won’t notice a change in the name resolution information once it gets cached.

If a name can be resolved after a packet is added to the list, its former entry won’t be changed. Try to resolve an Ethernet MAC address (e.g. 00:09:5b:01:02:03) to a human-readable name.

ARP name resolution (system service) : Wireshark will ask the operating system to convert an Ethernet address to the corresponding IP address (e.g. 00:09:5b:01:02:03 192.168.0.1). Ethernet codes (ethers file) : If the ARP name resolution failed, Wireshark tries to convert the Ethernet address to a known device name, which has been assigned by the user using an ethers file (e.g. 00:09:5b:01:02:03 home router).

Ethernet manufacturer codes (many file) : If neither ARP nor ethers returns a result, Wireshark tries to convert the first 3 bytes of an Ethernet address to an abbreviated manufacturer name, which has been assigned by the IEEE (e.g. 00:09:5b:01:02:03 Netgear_01:02:03). Try to resolve an IP address (e.g. 216.239.37.99) to a human-readable name.

For example, your web browser must resolve the host name portion of a URL before it can connect to the server. A given file might have hundreds, thousands, or millions of IP addresses so for usability and performance reasons Wireshark uses asynchronous resolution.

Both mechanisms convert IP addresses to human-readable (domain) names and typically use different sources such as the system hosts file (/etc/hosts) and any configured DNS servers. Since Wireshark doesn’t wait for DNS responses, the host name for a given address might be missing from a given packet when you view it the first time but be present when you view it subsequent times.

You can also edit your system hosts file, but that isn’t generally recommended. TCP/UDP port conversion (system service) : Wireshark will ask the operating system to convert a TCP or UDP port to its well known name (e.g. 80 HTTP).

Several network protocols use checksums to ensure data integrity. Applying checksums as described here is also known as redundancy checking.

Wireshark will validate the checksums of many protocols, e.g. IP, TCP, UDP, etc. It will do the same calculation as a “normal receiver” would do, and shows the checksum fields in the packet details with a comment, e.g. or .

This is avoided as incorrect connection data could “confuse” the internal database. Higher level checksums are “traditionally” calculated by the protocol implementation and the completed packet is then handed over to the hardware.

The network driver won’t calculate the checksum itself but will simply hand over an empty (zero or garbage filled) checksum field to the hardware. NoteChecksum offloading often causes confusion as the network packets to be transmitted are handed over to Wireshark before the checksums are actually calculated.

Turn off the checksum offloading in the network driver, if this option is available. Turn off checksum validation of the specific protocol in the Wireshark preferences.

Recent releases of Wireshark disable checksum validation by default due to the prevalence of offloading in modern hardware and operating systems. Wireshark provides a wide range of network statistics which can be accessed via the menu.

These statistics range from general information about the loaded capture file (like the number of captured packets), to statistics about specific protocols (e.g. statistics about the number of HTTP requests and responses captured). I/O Graphs visualizing the number of packets (or similar) in time.

Wireshark has many other statistics windows that display detailed information about specific protocols and might be described in a later version of this document. If a display filter is set, you will see values in the Captured column, and if any packets are marked, you will see values in the Marked column.

Each row contains the statistical values of one protocol. Protocol layers can consist of packets that won’t contain any higher layer protocol, so the sum of all higher layer packets may not sum up to the protocols' packet count.

Example: In the screenshot TCP has 98.5% but the sum of the subprotocols (TLS, HTTP, etc) is much less. This can be caused by continuation frames, TCP protocol overhead, and other dissected data.

For example RCMP replies and many tunneling protocols will carry more than one IP header. See Section 8.6.1, “The “Endpoints” Window” for a description of their common features.

Along with addresses, packet counters, and byte counters the conversation window adds four columns: the start time of the conversation (“Rel Start”) or (“Abs Start”), the duration of the conversation in seconds, and the average bits (not bytes) per second in each direction. Each row in the list shows the statistical values for exactly one conversation.

Name resolution will be done if selected in the window and if it is active for the specific protocol layer (MAC layer for the selected Ethernet endpoints page). Tithes window will be updated frequently so it will be useful even if you open it before (or while) you are doing a live capture.

The list of Ethernet or IP endpoints is usually what you’re looking for. IPA A concatenation of a 32 bit network number and 48 bit node address, by default the Ethernet interface’s MAC-48 address.

Each tab label shows the number of endpoints captured (e.g. the tab label “Ethernet · 4” tells you that four Ethernet endpoints have been captured). If no endpoints of a specific protocol were captured, the tab label will be greyed out (although the related page can still be selected).

Each row in the list shows the statistical values for exactly one endpoint. Name resolution will be done if selected in the window and if it is active for the specific protocol layer (MAC layer for the selected Ethernet endpoints page).

Note that in this example we have Mankind DB configured which gives us extra geographic columns. See Section 11.10, “Mankind Database Paths” for more information.

The Copy button will copy the list values to the clipboard in CSV (Comma Separated Values) or YAML format. Tithes window will be updated frequently, so it will be useful even if you open it before (or while) you are doing a live capture.

Shows the distribution of packet lengths and related information. Information is broken down by packet length ranges as shown above.

Ranges can be configured in the “Statistics Stats Tree” section of the Preferences Dialog. Average The arithmetic mean length of the packets in this range.

Burst Rate Packet bursts are detected by counting the number of packets in a given time interval and comparing that count to the intervals across a window of time. Statistics for the interval with the maximum number of packets are shown.

You can show statistics for a portion of the capture by entering a display filter into the Display filter entry and pressing Apply. Lets you plot packet and protocol data in a variety of ways.

As shown above, this window contains a chart drawing area along with a customizable list of graphs. Hovering over the graph shows the last packet in each interval except as noted below.

Style How to visually represent the graph’s data, e.g. by drawing a line, bar, circle, plus, etc. For MAX and MIN values, hovering and clicking the graph will show and take you to the packet with the MAX or MIN value in the interval instead of the most recent packet.

The chart as a whole can be configured using the controls under the graph list: Mouse drags / zooms When using the mouse inside the graph area, either drag the graph contents or select a zoom area.

The Help button will take you to this section of the User ’s Guide. The Copy button will copy values from selected graphs to the clipboard in CSV (Comma Separated Values) format.

Tiptoe can see a list of useful keyboard shortcuts by right-clicking on the graph. Zero values are shown in line graphs, and bar charts.

AFP CAMEL DCE-RPC Diameter Fiber Channel GTP H.225 RAS LDAP MEG ACO MCP NCP ONERC RADIUS SCSI SMB SMB2 SNMP As an example, the SMB2 service response time is described below in more detail.

The other Service Response Time windows will show statistics specific to their respective protocols, but will offer the same menu options. This window shows the number of transactions for each SMB2 opcode present in the capture file along with various response time statistics.

Right-clicking on a row will let you apply or prepare filters for, search for, or colorize a specific opcode. You can also copy all the response time information or save it in a variety of formats.

Statistics for HTTP request types and response codes. HTTP's request and response statistics based on the server address and host.

This enables analysts to see how one HTTP request leads to the next. Show different visual representations of the TCP streams in a capture.

Time Sequence (Stevens) This is a simple graph of the TCP sequence number over time, similar to the ones used in Richard Stevens’ “TCP/IP Illustrated” series of books. Time Sequence (trace) Shows TCP metrics similar to the trace utility, including forward segments, acknowledgments, selective acknowledgments, reverse window sizes, and zero windows.

RTT is based on the acknowledgment timestamp corresponding to a particular segment. Wireshark provides a wide range of telephony related network statistics which can be accessed via the menu.

The protocol specific statistics windows display detailed information of specific protocols and might be described in a later version of this document. This window will summarize the LTE MAC traffic found in the capture.

Each row in the middle pane shows statistical highlights for exactly one UE/Anti. In the lower pane, you can see the for the currently selected UE/Anti the traffic broken down by individual channel.

This window will summarize the LTE RLC traffic found in the capture. This will affect both the Plus counted and the display filters generated (see below).

The upper list shows summaries of each active UE. Each row in the lower list shows statistical highlights for individual channels within the selected UE.

The lower part of the windows allows display filters to be generated and set for the selected channel. The RTP analysis function takes the selected RTP stream (and the reverse stream, if possible) and generates a list of statistics on it.

Starting with basic data as packet number and sequence number, further statistics are created based on arrival time, delay, jitter, packet size, etc. The RTP Stream Analysis window further provides the option to save the RTP payload (as raw data or, if in a PCM encoding, in an Audio file).

Other options a to export and plot various statistics on the RTP streams. In order to use this feature your version of Wireshark must support audio and the codecs used by each RTP stream.

In the Real Time Streaming Protocol (RTS) menu the user can check the Packet Counter window. The user can filter, copy or save the data into a file.

Session Initiation Protocol (SIP) Flows window shows the list of all captured SIP transactions, such as client registrations, messages, calls and so on. Notes window will list both complete and in-progress SIP transactions.

Listen to the captured RTP stream if a decoder for the payload exists. In this window the user can filter, copy or save the statistics into a file.

Probe requests will be merged into an existing network if the SSID matches. Each row in the list shows the statistical values for exactly one wireless network.

Name resolution will be done if selected in the window and if it is active for the MAC layer. Tithes window will be updated frequently, so it will be useful, even if you open it before (or while) you are doing a live capture.

Wireshark ’s default behavior will usually suit your needs pretty well. However, as you become more familiar with Wireshark, it can be customized in various ways to suit your needs even better.

How to start Wireshark with command line parameters How to colorize the packet list How to control protocol dissection How to use the various preference settings Wireshark supports many command line parameters.

To see what they are, simply enter the command Wireshark -h and the help information shown in Help information available from Wireshark (or something similar) should be printed. We will examine each of the command line options in turn.

Filesize:value Stop writing to a capture file after it reaches a size of value kilobytes (where a kilobyte is 1000 bytes, not 1024 bytes). -b If a maximum capture file size was specified, this option causes Wireshark to run in “ring buffer” mode, with the specified number of files.

In “ring buffer” mode, Wireshark will write to several capture files. Their name is based on the number of the file and on the creation date and time.

If the optional duration is specified, Wireshark will also switch to the next file when the specified number of seconds has elapsed even if the current file is not completely filled up. Packets:value Switch to the next file after value number of packets were written, even if the current file is not completely filled up.

If you encounter packet drops while capturing, try to increase this size. Example: TCP.port==8888,HTTP -D, --list-interfaces Print a list of the interfaces on which Wireshark can capture, then exit.

The number can be especially useful on Windows, where the interface name is a GUID. -h, --help This option requests Wireshark to print its version and usage instructions (as shown here) and exit.

If you’re using UNIX, net stat -i, config -a or IP link might also work to list interface names, although not all versions of UNIX support the -a flag to config. Data read from pipes must be in standard liberal format.

-k The -k option specifies that Wireshark should start capturing packets immediately. This option requires the use of the -i parameter to specify the interface that packet capture will occur from.

-l This option turns on automatic scrolling if the packet list pane is being updated automatically as packets arrive during a capture (as specified by the -S flag). -L, --list-data-link-types List the data link types supported by the interface and exit.

The example above would dissect packets with a liberal data link type 147 as HTTP, just as if you had configured it in the DLT_ USER protocol preferences. -p, --no-promiscuous-mode Don’t put the interface into promiscuous mode.

This is used for special cases, e.g. starting Wireshark from a known location on a USB stick. Wireshark will only capture Naples bytes of data for each packet.

-S This option specifies that Wireshark will display packets as it captures them. This is the same as “Update list of packets in real time” in the “Capture Options” dialog box.

-t

D Delta, which specifies that timestamps are relative to the previous packet. Dd: Delta, which specifies that timestamps are relative to the previous displayed packet.

E Epoch, which specifies that timestamps are seconds since epoch (Jan 1, 1970 00:00:00) u Absolute, which specifies that actual times be displayed for all packets in UTC. -u Show timestamps as seconds (“s”, the default) or hours, minutes, and seconds (“HMS”) -v, --version This option requests Wireshark to print out its version information and exit.

-w This option sets the name of the file to be used to save captured packets. Lua_script:argument Tells Wireshark to pass the given argument to the LA script identified by sum, which is the number indexed order of the lua_script command.

Read_format: Tells Wireshark to use a specific input file type, instead of determining it automatically. -z Get Wireshark to collect various types of statistics and display the result in a window that updates in semi-real time.

For the currently implemented statistics consult the Wireshark manual page. You can set up Wireshark so that it will colorize packets according to a display filter.

This will create a coloring rule based on the currently selected conversation. It will try to create a conversation filter based on TCP first, then UDP, then IP and at last Ethernet.

Temporary filters can also be created by selecting the menu items when right-clicking in the packet detail pane. The color chooser appearance depends on your operating system.

As Wireshark tries to find the right dissector for each packet (using static “routes” and heuristics “guessing”), it might choose the wrong dissector in your specific case. For example, suppose you disabled the IP protocol and selected a packet containing Ethernet, IP, TCP, and HTTP information.

Note that typing a few letters of the protocol name in the search box will limit the list to those protocols that contain these letters. OK Save and apply the changes and close the dialog box, see Appendix B, Files and Folders for details.

The “Decode As” functionality lets you temporarily divert specific protocol dissections. It will then contain a new line based on the currently selected packet.

These settings will be lost if you quit Wireshark or change profile unless you save the entries. OK Apply the user specified decodes and close the dialog box.

Simply select the ( on macOS) and Wireshark will pop up the Preferences' dialog box as shown in Figure 11.6, “The preferences' dialog box”, with the User Interface” page as default. On the left side is a tree where you can select the page to be shown.

The OK button will apply the preferences settings and close the dialog. The Cancel button will restore all preferences settings to the last saved state.

The “Advanced” pane will let you view and edit all of Wireshark ’s preferences, similar to about:config and chrome:flags in the Firefox and Chrome web browsers. You can also pass preference names to Wireshark and Shark on the command line.

Some recent settings (recent), such as pane sizes in the Main window (Section 3.3, “The Main window”), column widths in the packet list (), all selections in the menu (Section 3.7, “The “View” Menu”) and the last directory navigated to in the “File Open” dialog. This copies the configuration of the profile currently selected in the list.

For example defining a display filter macro named tcp_conv whose text is Display Filter Macros can be managed with a user table, as described in Section 11.7, User Table”, by selecting from the menu.

Wireshark uses this table to map ESS Security Category attributes to textual representations. The values to put in this table are usually found in an XML Spin, which is used for defining security labels.

Database path name This specifies a directory containing Mankind data files. The locations for your data files are up to you, but /USR/share/Geo IP and /var/lib/Geo IP are common on Linux and C:\Programmatic\Geo IP, C:\Program Files\ Wireshark \Geo IP might be good choices on Windows.

Previous versions of Wireshark supported Mankind’s original Geo IP Legacy database format. They are no longer supported and Mankind stopped distributing Zeolite Legacy databases in April 2018.

Wireshark can decrypt Encrypted Payloads of IKEv2 (Internet Key Exchange version 2) packets if necessary information is provided. If you want to decrypt IKEv1 packets or ESP packets, use Log Filename setting under ISAM protocol preference or settings under ESP protocol preference respectively.

This field takes hexadecimal string without “0x” prefix and the length must be 16 hex chars (represents 8 octets). This field takes hexadecimal string without “0x” prefix and the length must be 16 hex chars (represents 8 octets).

This field takes hexadecimal string without “0x” prefix and its length must meet the requirement of the encryption algorithm selected. This field takes hexadecimal string without “0x” prefix and its length must meet the requirement of the encryption algorithm selected.

SK_ai Key used to calculate Integrity Checksum Data for IKEv2 packets from responder to initiator. This field takes hexadecimal string without “0x” prefix and its length must meet the requirement of the integrity algorithm selected.

SK_ar Key used to calculate Integrity Checksum Data for IKEv2 packets from initiator to responder. This field takes hexadecimal string without “0x” prefix and its length must meet the requirement of the integrity algorithm selected.

In many cases, they are used in an extension mechanism so that new object identifiers (and associated values) may be defined without needing to change the base standard. Wireshark uses this table to allow the user to define the name and syntax of Object Identifiers that Wireshark does not know about (for example, a privately defined X.400 extension).

Name The name that should be displayed by Wireshark when the Object Identifier is dissected e.g. (“c”); Syntax The syntax of the value associated with the Object Identifier. Wireshark uses this table to map a presentation context identifier to a given object identifier when the capture does not contain a PRES package with a presentation context definition list for the conversation.

Syntax Name Did The object identifier representing the abstract syntax name, which defines the protocol that is carried over this association. Wireshark uses this table to map specific protocols to a certain DPC/SSN combination for CCP.

If your copy of Wireshark supports lib SMI, you can specify a list of MIB and PIB modules here. If your copy of Wireshark supports lib SMI, you can specify one or more paths to MIB and PIB modules here.

Wireshark automatically uses the standard SMI path for your system, so you usually don’t have to add anything here. Wireshark uses this table to map specific-trap values to user defined descriptions in a Trap PDU.

Wireshark uses this table to verify authentication and to decrypt encrypted SNMPv3 packets. Privacy protocol Which encryption algorithm to use (either “DES” or “AES”).

Wireshark doesn’t read these St files, it uses a table that helps it identify which the lowest layer protocol to use. For example, the variant wire type in proof packet may be converted to int32, int64, uint32, uint64, sint32, sint64, built or ENIM field types of protocol buffers language.

Wireshark should be configured with Protocol Buffers language files (*.photo) to enable proper dissection of proof data (which may be payload of GRC) based on the message, ENIM and field definitions. For example, if you defined a photo file with path d:/my_photo_files/hello world.photo and the hello world.photo contains a line of import “google/proof/any.photo”; because the any type of official proof library is used.

The configuration for the proof search paths is a user table, as described in Section 11.7, User Table”, with the following fields: Load all files If this option is enabled, Wireshark will load all *.photo files in this directory and its subdirectories when Wireshark startup or proof search paths preferences changed.

Note that the source directories that configured to proof official or third libraries' path (like d:/protobuf-3.4.1/include/) should not be set to load all files, that may cause unnecessary memory use. If the payload of UDP on certain ports is Proof encoding, Wireshark use this table to know which Proof message type should be used to parsing the data on the specified UDP port(s).

The configuration for UDP Port(s) to Proof message type maps is a user table, as described in Section 11.7, User Table”, with the following fields: The message type is allowed to be empty, that means let Proof to dissect the data on specified UDP ports as normal wire type without precise definitions.

The hello world is package name, HelloRequest is message type. Well, to keep it very short, with MATE you can create user configurable extension(s) of the display filter engine.

MATE was written to help troubleshooting gateways and other systems where a “use” involves more protocols. However, MATE can be used as well to analyze other issues regarding an interaction between packets like response times, incompleteness of transactions, presence/absence of certain attributes in a group of Plus and more.

MATE is a Wireshark plugin that allows the user to specify how different frames are related to each other. Once the Plus are related MATE will create a “protocol” tree with fields the user can filter with.

Other than that MATE allows filtering frames based on response times, number of Plus in a group and a lot more. (MATE’s original goal) Filter all packets of all calls using various protocols based on the release cause of one of its “segments”.

Run Wireshark and check if the plugin is installed correct (MATE should appear in HelpAboutPlugins) Get a configuration file e.g. TCP.mate (see Mate/Examples for more) and place it somewhere on your hard disk. Go to PreferencesProtocolsMATE and set the config filename to the file you want to use (you don’t have to restart Wireshark) Load a corresponding capture file (e.g. HTTP.cap) and see if MATE has added some new display filter fields, something like: mate tcp_pdu:1tcp_ses:1 or, at prompt: path_to/ Wireshark -o “mate.config: TCP.mate” -r HTTP.cap.

MATE creates a filterable tree based on information contained in frames that share some relationship with information obtained from other frames. The way these relationships are made is described in a configuration file.

The configuration file tells MATE what makes a PDU and how to relate it to other Plus. From now on, I will use the term “PDU” to refer to the objects created by MATE containing the relevant information extracted from the frame; I’ll use “frame” to refer to the “raw” information extracted by the various dissectors that reanalyzed the frame.

For every PDU, MATE checks if it belongs to an existing “Group of Plus” (GOP). How and when do Plus belong to Goes is described in the configuration file as well.

Every time a GOP is assigned a new PDU, MATE will check if it matches the conditions to make it belong to a “Group of Groups” (Gog). Naturally the conditions that make a GOP belong to a Gog are taken from the configuration file as well.

Once MATE is done analyzing the frame it will be able to create a “protocol” tree for each frame based on the Plus, the Goes they belong to and naturally any Gog's the former belongs to. Information in MATE is contained in Attribute/Value Pairs (Alps).

Their Apply will be matched in various ways against others coming from the configuration file. MATE will be instructed how to extract Alps from frames in order to create a PDU with an AGPL.

In MATE the relationship between Plus is a GOP, it has an AGPL as well. Information used by MATE to relate different frames is contained in Attribute/ Value Pairs (Alps).

Capitalized names are reserved for configuration parameters (we’ll call them keywords); nothing forbids you from using capitalized strings for other things as well but it probably would be confusing. I’ll avoid using capitalized words for anything but the keywords in this document, the reference manual, the examples and the base library.

Names that start with a “.” would be very confusing as well because in the old grammar, AGPL transformations use names starting with a “.” to indicate they belong to the replacement AGPL. The values extracted from fields use the same representation as they do in filter strings except that no quotes are used.

The way two Alps with the same name might match is described by the operator. Remember two Alps won’t match unless their names are identical.

Every PDU, GOP and Gog has an AGPL that contains the information regarding it. The rules that MATE uses to group Plus and Goes are AGPL operations.

However, we can have more than one AVP with the same name in an AGPL as long as their values are different. Data Apply that contain information extracted from frames.

In the second phase, if a PDU has been extracted from the frame, MATE will try to group it to other Plus into a GOP (Group of Plus) by matching the key criteria given by a GOP declaration. By default, it is an empty string which means: do not configure MATE.

There are 4 types of declarations: Transform, PDU, GOP and Gog. MATE will look in the tree of every frame to see if there is useful data to extract, and if there is, it will create one or more PDU objects containing the useful information.

MATE will fetch from the field’s tree those fields that are defined in the Section 12.8.1, “PDS’s configuration actions” declaration whose initial offset in the frame is within the boundaries of the current Photo and those of the given Transport and Payload statements. MATE will fetch from the field’s tree those fields that are defined in the Section 12.8.1, “PDS’s configuration actions” AGPL whose initial offset in the frame is within the boundaries of the current Photo and those of the various assigned Transports.

Once MATE has found a Photo field for which to create a PDU from the frame it will move backwards in the frame looking for the respective Transport fields. After that it will create Alps named as each of those given in the rest of the AGPL for every instance of the fields declared as its values.

MATE will choose only the closest transport boundary per “protocol” in the frame. This way we’ll have all Plus for every Photo that appears in a frame match its relative transports.

This allows to assign the right Transport to the PDU avoiding duplicate transport protocol entries (in case of tunneled IP over IP for example). The Criteria statement is given an action (Except or Reject), a match mode (Strict, Loose or Every) and an AGPL against which to match the currently extracted one.

Once the fields have been extracted into the PDU’s AGPL, MATE will apply any declared transformation to it. However, it’s useful to know that once the AGPL for the PDU is created, it may be transformed before being analyzed.

That way we can massage the data to simplify the analysis. Every successfully created PDU will add a MATE tree to the frame dissection.

Once MATE has created the Plus it passes to the PDU analysis phase. During the PDU analysis phase MATE will try to group Plus of the same type into 'Groups of Plus' (aka *Gop×s) and copy some Alps from the PDU’s AGPL to the GOP’s AGPL.

If it is a Start match, MATE will check whether that GOP has been already stopped. Once the PDU has been assigned to the GOP, MATE will check whether the PDU matches the Stop, if it happens, MATE will mark the Go pas stopped.

Other than the PDU’s tree, this one contains information regarding the relationship between the Plus that belong to the GOP. Mate.DNS_req. StartTime time (in seconds) passed since beginning of capture until GOP’s start.

A filterable list of frame numbers of the plus of this GOP Duration, which is defined for every GOP regardless of its state, and give the time passed between its Start PDU and the last PDU that was assigned to that GOP.

When Goes are created, or whenever their AGPL changes, Goes are (re)analyzed to check if they match an existent group of groups (Gog) or can create a new one. In the first phase, the still unassigned GOP is checked to verify whether it belongs to an already existing Gog or may create a new one.

There are several reasons for the author to believe that this feature needs to be reimplemented, so probably there will be deep changes in the way this is done in the near future. This section of the documentation reflects the version of MATE as of Wireshark 0.10.9; in future releases this will change.

The first thing we have to do configuring a Gog is to tell MATE that it exists. Then we have to tell MATE what to look for a match in the candidate Goes.

Mate.HTTP_use. Duration time elapsed between the first frame of a Gog and the last one assigned to it. Transforms can be used as helpers to manipulate an item’s AGPL before it is processed further.

AGPL Transformations are declared in the following way: They will be executed in the order they appear in the config file whenever they are invoked.

The default value Insert (which may be omitted) causes the modify_avpl to be merged to the existing data AGPL, the Replacement causes all the matching Alps from the data AGPL to be replaced by the modify_avpl. The modify_avpl may be an empty one; this comes useful in some cases for both Insert and Replace modification modes.

In case of GOP and Gog, the list of transforms is applied against their respective Apply when they are created and every time they change. Using Transforms we can add more than one start or stop condition to a GOP.

Marking Goes and Gog's to filter them easily MATE was originally written by Luis Ont anon, a Telecommunications systems troubleshooter, as a way to save time filtering out the packets of a single call from huge capture files using just the calling number.

Later he used the time he had saved to make it flexible enough to work with protocols other than the ones he was directly involved with. Use mate.http_use. Duration > 5.5 to filter frames based on the time it takes to load a complete page from the DNS request to resolve its name until the last image gets loaded.

Use mate.HTTP_use.client == “10.10.10.20” & mate.HTTP_use.host == “www.example.com” to isolate DNS and HTTP packets related to a visit of a certain user. Use mate.http_req. Duration > 1.5 to filter all the packets of HTTP requests that take more than 1.5 seconds to complete.

Supposing you have a mate plugin already installed you can test it with the current Wireshark version. First we’ll tell MATE how to create a GOP for each DNS request/response.

MATE needs to know what makes a DNS PDU. Once we’ve told MATE how to extract dns_pdus we’ll tell it how to match requests and responses and group them into a GOP.

That means that in order to belong to the same GOP, dns_pdus have to have both addresses and the request id identical. At this point, if we open a capture file using this configuration, we are able to use a display filter mate.dns_req. Time > 1 to see only the packets of DNS requests that take more than one second to complete.

Filtering with mate.http_req. Time > 1 will give all the requests where the response header takes more than one second to come filtering with mate.http_req. Duration > 1.5 will show those request that take more than 1.5 seconds to complete. You have to know that mate.xxx. Time gives the time in seconds between the PDU matching the Upstart and the PDU matching the HopStop (yes, you can create timers using this!).

To be able to group DNS and HTTP requests together, we need to import into the Plus and Goes some part of information that both those protocols share. We also have to tell MATE to copy the host attribute from the Plus to the Goes, we do this using Extra.

Using the Member statements we tell MATE that HTTP_req’s with the same *host belong to the same Gog, same thing for *DNS_req’s. So far we have instructed mate to group every packet related to sessions towards a certain host.

This configuration works fine if used for captures taken at the client’s side but deeper in the network we’d got a real mess. MATE has a tool that can be used to resolve this kind of grouping issues.

Next, we invoke the transform by adding the following line after the Extract list of the dns_pdu PDU: This is possible due to the fact that the Match clauses in the Transform are executed one by one until one of them succeeds.

Once we got all what we need in the Plus, we have to tell MATE to copy the attribute client from the Plus to the respective Goes, by adding client to Extra lists of both GOP declarations: On top of that, we need to modify the old declarations of GOP key to new ones that include both client and host.

So we change the Gog Member declarations the following way: Anyway they are meant to help users understanding how to configure MATE.

The following example creates a Go Pout of every TCP session. This probably would do fine in 99.9% of the cases but 10.0.0.1:2010.0.0.2:22 and 10.0.0.1:2210.0.0.2:20 would both fall into the same GOP if they happen to overlap in time.

Filtering with mate.tcp_ses.I'd == 3 will show all the packets for the third TCP session MATE has found. This configuration allows to tie a complete passive ftp session (including the data transfer) in a single Gog.

Spying on people, in addition to being immoral, is illegal in many countries. With this example, all the components of an MMS send or receive will be tied into a single Gog.

Note that this example uses the Payload clause because MMS delivery uses Muse over either HTTP or WSP. The MATE library (will) contains GOP definitions for several protocols.

For Every protocol with a library entry, we’ll find defined what from the PDU is needed to create a GOP for that protocol, eventually any criteria and the very essential GOP definition (i.e. Golden, Upstart and HopStop). Will create a GOP containing every request and it’s response (eventually retransmissions too).

Most protocol definitions here will create one GOP for every Call Leg unless stated. These “pairs” (actually tuples) are made of a name, a value and, in case of configuration Alps, an operator.

Two attributes won’t match unless their names are identical. Capitalized names are reserved for keywords (you can use them for your elements if you want but I think it’s not the case).

MATE attribute names can be used in Wireshark ’s display filters the same way as names of protocol fields provided by dissectors, but they are not just references to (or aliases of) protocol fields. The values extracted from fields use the same representation as they do in filter strings.

Currently, only match operators are defined (there are plans to (re)add transform attributes but some internal issues have to be solved before that). Will match only if the value strings aren’t equal.

Individual teams of the list inside the curly braces are separated using | character. Contains ~ will match if the configuration value string matches a substring of the characters of the data AVP’s value string.

This operator matches if the value strings of two Alps are not equal. The “contains” operator will match if the data AVP value contains a string identical to the configuration AVP value.

Plus, Goes and Goes use an AGPL to contain the tracing information. There are three types of match operations that can be performed between Apply.

The replacement means that the existing data Alps are dropped and the replacement AGPL from the configuration is Merged to the data AGPL of the PDU/GOP/Gog. Its result AGPL contains all the data Alps that matched.

Notes of current (2.0.1), Loose Match does not work as described here, see issue 12184. Its result AGPL contains all the data Alps that matched.

Notes of current (2.0.1), Loose Match does not work as described here, see issue 12184. The result AGPL contains all the data Alps that matched.

Between the result of a key match and the GOP’s or Gog’s AGPL, between the result of an Extra match and the GOP’s or Gog’s AGPL, between the result of a Transform match and PDU’s/GOP’s AGPL. If the operation specified by the Match clause is Replaced, the result AGPL of the match is removed from the item’s AGPL before the modify_avpl is merged into it.

The list of Match rules inside a Transform is processed top to bottom; the processing ends as soon as either a Match rule succeeds or all have been tried in vain. Regardless whether the individual transforms succeed or fail, the list is always executed completely and in the order given, i.e. left to right.

The following configuration Apply deal with PDU creation and data extraction. In each frame of the capture, MATE will look for source proto_name 's Plus in the order in which the declarations appear in its configuration and will create Plus of every type it can from that frame, unless specifically instructed that some PDU type is the last one to be looked for in the frame.

The complete declaration of a PDU looks as below; the mandatory order of the diverse clauses is as shown. The name is a mandatory attribute of a PDU declaration.

It is chosen arbitrarily, except that each name may only be used once in MATE’s configuration, regardless the class of an item it is used for. The name is used to distinguish between different types of Plus, Goes, and Gog's.

In such case, all of them are created from each source PDU matching their Photo, Transport, and Payload clauses, while the bodies of their declarations may be totally different from each other. Together with the Accept (or Reject) clauses, this feature is useful when it is necessary to build the PDU’s AGPL from different sets of source fields depending on contents (or mere presence) of other source fields.

Every instance of the protocol proto_name PDU in a frame will generate one PDU with the Alps extracted from fields that are in the proto_name 's range and/or the ranges of underlying protocols specified by the Transport list. In order that MATE would extract an attribute from a frame’s protocol tree, the area representing the field in the hex display of the frame must be within the area of either the Photo or its relative Transport s. Transport s are chosen moving backwards from the protocol area, in the order they are given.

Transport TCP/IP/IP that “logically” should select the encapsulating IP header too doesn’t work so far. Once we’ve selected the Photo and Transport ranges, MATE will fetch those protocol fields belonging to them whose extraction is declared using the Extract clauses for the PDU type.

Other than the PDU’s Photo and its Transport protocols, there is also a Payload attribute to tell MATE from which ranges of Proto's payload to extract fields of a frame into the PDU. In order to extract an attribute from a frame’s tree the highlighted area of the field in the hex display must be within the area of the Proto's relative payload(s).

Payload s are chosen moving forward from the protocol area, in the order they are given. Once we’ve selected the Payload ranges, MATE will fetch those protocol fields belonging to them whose extraction is declared using the Extract clauses for the PDU type.

Each Extract clause tells MATE which protocol field value to extract as an AVP value and what string to use as the AVP name. The protocol fields are referred to using the names used in Wireshark display filters.

If there is more than one such protocol field in the frame, each instance that fulfills the criteria stated above is extracted into its own AVP. The AVP names may be chosen arbitrarily, but to be able to match values originally coming from different Plus (e.g., hostname from DNS query and a hostname from HTTP GET request) later in the analysis, identical AVP names must be assigned to them and the dissectors must provide the field values in identical format (which is not always the case).

The Transform clause specifies a list of previously declared Transform s to be performed on the PDU’s AGPL after all protocol fields have been extracted to it. This clause tells MATE whether to use the PDU for analysis.

Once every attribute has been extracted and eventual transform list has been executed, and if the Criteria clause is present, the PDU’s AGPL is matched against the match AGPL; if the match succeeds, the action specified is executed, i.e. the PDU is accepted or rejected. The default behaviors used if the respective keywords are omitted are Strict and Accept.

If set to TRUE, MATE will destroy the PDU if it cannot assign it to a GOP. If set to FALSE (the default if not given), MATE will keep them.

If set to FALSE (the default if not given), MATE will keep the PDU attributes. If set to FALSE (the default if not given), MATE will continue to look for Plus of other types in the frame.

Declares a GOP type and its rematch candidate key. It is chosen arbitrarily, except that each name may only be used once in MATE’s configuration, regardless the class of an item it is used for.

The name is used to distinguish between different types of Plus, Goes, and Gog's. The name of Plus which this type of GOP is supposed to be grouping.

If given, it tells MATE what match_avpl must a PDU’s AGPL match, in addition to matching the GOP’s key, in order to start a GOP. The PDU’s Alps matching the match_avpl are not automatically copied into the GOP’s AGPL.

If given, it tells MATE what match_avpl must a PDU’s AGPL match, in addition to matching the GOP’s key, in order to stop a GOP. The PDU’s Alps matching the match_avpl are not automatically copied into the GOP’s AGPL.

The Transform clause specifies a list of previously declared Transform s to be performed on the GOP’s AGPL after the Alps from each new PDU, specified by the key AGPL and the Extra clause’s match_avpl, have been merged into it. The default value of zero has an actual meaning of infinity, as it disables this timer, so all Plus matching the Stop PED GOP’s key will be assigned to that GOP unless they match the Start condition.

If TRUE, the default, the subtree with the timers is added to the GOP’s tree. Declares a Gog type and its rematch candidate key.

It is chosen arbitrarily, except that each name may only be used once in MATE’s configuration, regardless the class of an item it is used for. The name is used to distinguish between different types of Plus, Goes, and Gog's.

Defines the key AGPL for the Gog individually for each GOP type game. Although the key Apply are specified separately for each of the Member game s, in most cases they are identical, as the very purpose of a Gog is to group together Goes made of Plus of different types.

A (floating) number of seconds after all the Goes assigned to a Gog have been released during which new Goes matching any of the session keys should still be assigned to the existing Gog instead of creating a new one. The Transform clause specifies a list of previously declared Transform s to be performed on the Gog’s AGPL after the Alps from each new GOP, specified by the key AGPL and the Extra clause’s match_avpl, have been merged into it.

If TRUE, the default, the subtree with the timers is added to the Gog’s tree. The Settings' config element is used to pass to MATE various operational parameters.

How long in seconds after all the goes assigned to a Gog have been released new goes matching any of the session keys should create a new Gog instead of being assigned to the previous one. Whether the AGPL of every PDU should be deleted after it was being processed (saves memory).

Setting it to FALSE can save you from a headache if your config does not work. Set it to TRUE to save memory if unassigned Plus are useless.

The following settings are used to debug MATE and its configuration. All levels are integers ranging from 0 (print only errors) to 9 (flood me with junk), defaulting to 0.

The {{{path/name}}} is a full path to the file to which debug output is to be written. If the statement is missing, debug messages are written to console, which means they are invisible on Windows.

It is an integer ranging from 0 (print only errors) to 9 (flood me with junk). Sets the level of debugging for messages regarding PDU creation.

It is an integer ranging from 0 (print only errors) to 9 (flood me with junk). Sets the level of debugging for messages regarding PDU analysis (that is how do they fit into ? GoPs).

It is an integer ranging from 0 (print only errors) to 9 (flood me with junk). Sets the level of debugging for messages regarding GOP analysis (that is how do they fit into ? GoGs).

It is an integer ranging from 0 (print only errors) to 9 (flood me with junk). Wireshark provides you with additional information generated out of the plain packet data or it may need to indicate dissection problems.

Messages generated by Wireshark are usually placed in square brackets (“”). You’ll have to look into the specific situation to determine the reason.

The packet size was limited during capture, see “Limit each packet to n bytes” at the Section 4.5, “The “Capture Options” Dialog Box”. While dissecting, the current protocol dissector was simply running out of packet bytes and had to give up.

There’s nothing else you can do now, except to repeat the whole capture process again with a higher (or no) packet size limitation. You can directly jump to the corresponding response packet by double-clicking on the message.

You can directly jump to the corresponding packet by double-clicking on this message. However, it has some drawbacks: it’s not extensible and lacks some information that would be really helpful (e.g. being able to add a comment to a packet such as “the problems start here” would be really nice).

At the start of each liberal capture file some basic information is stored like a magic number to identify the liberal file format. The most interesting information of this file start is the link layer type (Ethernet, 802.11, MPLS, etc).

Pacing files can optionally save name resolution information. We indicate the location of the top-level folders under which configuration files and plugins are stored here, giving them placeholder names independent of their actual location, and use those names later when giving the location of the folders for configuration files and plugins.

Tip list of the folders Wireshark actually uses can be found under the Folders tab in the dialog box shown when you select About Wireshark from the Help menu. Otherwise, INSTALL DIR is the top-level directory under which reside the subdirectories in which components of Wireshark are installed.

This will typically be /USR if Wireshark is bundled with the system (for example, provided as a package with a Linux distribution) and /USR/local if, for example, you’ve built Wireshark from source and installed it. At program start, if there is a filters file in the personal configuration folder, it is read.

If there isn’t a filters file in the personal configuration folder, then, if there is a filters file in the global configuration folder, it is read. Colorfilters This file contains all the color filters that you have defined and saved.

At program start, if there is a color filters file in the personal configuration folder, it is read. If there isn’t a color filters file in the personal configuration folder, then, if there is a color filters file in the global configuration folder, it is read.

Dfilter_buttons This file contains all the display filter buttons that you have defined and saved. At program start, if there is a dfilter_buttons file in the personal configuration folder, it is read.

Dfilter_macros This file contains all the display filter macros that you have defined and saved. At program start, if there is a dfilter_macros file in the personal configuration folder, it is read.

When you press the Save button in the “Display Filter Macros” dialog box, all the current display filter macros are written to the personal display filter macros file. Dfilters This file contains all the display filters that you have defined and saved.

At program start, if there is a filters file in the personal configuration folder, it is read. If there isn’t a filters file in the personal configuration folder, then, if there is a filters file in the global configuration folder, it is read.

Disabled_photos Each line in this file specifies a disabled protocol name. At program start, if there is a disabled_protos file in the global configuration folder, it is read first.

Ethers When Wireshark is trying to translate a hardware MAC address to a name, it consults the ethers file in the personal configuration folder first. Each line in these files consists of one hardware address and name separated by whitespace.

The digits of hardware addresses are separated by colons (:), dashes (-) or periods(.). The settings from this file are read in when a MAC address is to be translated to a name, and never written by Wireshark.

At program start, if there is a hosts file in the global configuration folder, it is read first. The settings from this file are read in at program start and never written by Wireshark.

Ipxnets When Wireshark is trying to translate an IPA network number to a name, it consults the spinets file in the personal configuration folder first. The settings from this file are read in when an IPA network number is to be translated to a name, and never written by Wireshark.

The entries in this file are used to translate MAC address prefixes into short and long manufacturer names. Each line consists of a MAC address prefix followed by an abbreviated manufacturer name and the full manufacturer name.

Prefixes 24 bits long by default and may be followed by an optional length. The settings from this file are read in at program start and never written by Wireshark.

It is a simple text file containing statements of the form: At program start, if there is a preferences file in the global configuration folder, it is read first.

At program start, if there is a services file in the global configuration folder, it is read first. The settings from these files are read in at program start and never written by Wireshark.

Ss7pcs Wireshark uses the ss7pcs file to translate SS7 point codes to node names. At program start, if there is a ss7pcs file in the personal configuration folder, it is read.

Each line in this file consists of one network indicator followed by a dash followed by a point code in decimal and a node name separated by whitespace or tab. The settings from this file are read in at program start and never written by Wireshark.

At program start, if there is a subnets file in the personal configuration folder, it is read first. The settings from these files are read in at program start and never written by Wireshark.

If there is a plans file in the currently active profile folder, it is used. Each line in this file consists of one VLAN tag ID and a describing name separated by whitespace or tab.

The settings from this file are read in at program start or when changing the active profile and are never written by Wireshark. There is another hierarchical level for each Wireshark plugin type (Wireshark, lib wiretap and codecs).

Noted provide better support for binary plugins this folder changed in Wireshark 2.5. It is recommended to use the new folder but for LA scripts only you may continue to use $XDG_CONFIG_HOME/ Wireshark /plugins for backward-compatibility.

In case of duplicate file names between old and new the new folder wins. Here you will find some details about the folders used in Wireshark on different Windows versions.

As already mentioned, you can find the currently used folders in the “About Wireshark dialog. Noted you’ve upgraded to a new Windows version, your profile might be kept in the former location.

The following guides you to the right place where to look for Wireshark ’s profile data. Some larger Windows environments use roaming profiles.

If this is the case the configurations of all programs you use won’t be saved on your local hard drive. Wireshark uses the folder which is set by the TMP DIR or TEMP environment variable.

Wireshark comes with an array of command line tools which can be helpful for packet analysis. You can find more information about all of Wireshark ’s command line tools on the website.

Shark is a terminal oriented version of Wireshark designed for capturing and displaying packets when an interactive user interface isn’t necessary or available. For example, you might want to do a remote capture and either don’t have GUI access or don’t have Wireshark installed on the remote machine.

Older versions of pump truncate packets to 68 or 96 bytes. You will have to specify the correct interface and the name of a file to save into.

By default, Dump cap uses the cap library to capture traffic from the first available network interface and writes the received raw packet data, along with the packets’ time stamps into a pacing file. The capture filter syntax follows the rules of the cap library.

Information can be printed in human and machine-readable formats. Raw shark reads a stream of packets from a file or pipe, and prints a line describing its output, followed by a set of matching fields for each packet on stout.

Merge cap can read liberal capture files, including those of pump. In addition, Merge cap can read capture files from snoop (including Short) and snoop, Analyzer, Sniffer (compressed or uncompressed), Microsoft Network Monitor, AIX’s trace, Betray, Sniffer Pro, RAD COM’s WAN/LAN analyzer, Lu cent/Ascend router debug output, HP-UX’s nettle, and the dump output from Toshiba’s ISDN routers.

Merge cap is also capable of reading any of these file formats if they are compressed using GZIP. Merge cap recognizes this directly from the file; the “.go” extension is not required for this purpose.

Packets from the input files are merged in chronological order based on each frame’s timestamp, unless the -a flag is specified. Merge cap assumes that frames within a single capture file are already stored in chronological order.

If the -s flag is used to specify a snapshot length, frames in the input file with more captured data than the specified snapshot length will have only the amount of data specified by the snapshot length written to the output file. This may be useful if the program that is to read the output file cannot handle packets larger than a certain size (for example, the versions of snoop in Polaris 2.5.1 and Polaris 2.6 appear to reject Ethernet frames larger than the standard Ethernet MTU, making them incapable of handling gigabit Ethernet captures if jumbo frames were used).

Note that this merely forces the encapsulation type of the output file to be the specified type; the packet headers of the packets will not be translated from the encapsulation type of the input capture file to the specified encapsulation type (for example, it will not translate an Ethernet capture to an FDDI capture if an Ethernet capture is read and -T FDDI is specified). There may be some occasions when you wish to convert a hex dump of some network traffic into a liberal file.

Text2pcap is a program that reads in an ASCII hex dump and writes the data described into a cap or pacing capture file. Text2pcap is also capable of generating dummy Ethernet, IP, UDP, TCP or SMTP headers, in order to build fully processable packet dumps from hex dumps of application-level data only.

In other words, each byte is individually displayed and surrounded with a space. Any text before the offset is ignored, including email forwarding characters “>”.

An offset is recognized as being a hex number longer than two characters. If not, the first packet is timestamped with the current time the conversion takes place.

Any line beginning with #TEXT2PCAP is a directive and options can be inserted after this command to be processed by text2pcap. Currently, there are no directives implemented; in the future, these may be used to give more fine-grained control on the dump and the way it should be processed e.g. timestamps, encapsulation type etc.

Text2pcap also allows the user to read in dumps of application-level data, by inserting dummy L2, L3 and L4 headers before each packet. For more information on text2pcap consult your local manual page (man text2pcap) or the online version.

Reordercap lets you reorder a capture file according to the packets timestamp. As with the original license and documentation distributed with Wireshark, this document is covered by the GNU General Public License (GNU GPL).

It explains all the things that you are allowed to do with this code and documentation. Wireshark is used to analyze inbound and outbound packets from your system.

This helps me analyze the exact data that is being sent to a particular website. You can download Wireshark for free, so I would recommend everyone to install it.

It is not only informative and helps in troubleshooting but it is fun to watch what is going on behind the scenes. Immediately the packets start getting captured and you can view them in the Wireshark window.

Now as we need to find the GET and POST packets (which follow the HTTP protocol) we need to set an appropriate filter for it. Paste the following expression in it, HTTP.request.method == GET or HTTP.request.method == POST and hit enter.

You can save it for future use as well, so that you don’t need to remember it every time you wish to filter packets. It also shows the version, i.e. 1.1 If-Modified-Since is one of the header messages, it indicates that the request is just to check if the URL is modified since the time specified.

So now that you know how to analyze packets using Wireshark, go try your hands at it and see what data is being sent to which sites. You will be surprised to know how many chrome extensions sent data to their servers behind your back.

Check out the various packets the torrent client keeps sending and receiving. Us 5.1.1 officially added a remote packet capture option to the phone in order to troubleshoot issue and provide Wireshark traces if required.

The Us 5.1.0 Admin Guide describes this on page 170 in the Remote Packet Capture for Logs section. In the above photo the Phone uses a VLAN 242 but on a Trio as an example the Wi-Fi interface can be displayed and selected.

Capture > Options > Output Filename: Test file.cap or Test file.pacing The above will create 100 MB files up until Wireshark is stopped Ticking Use a ring buffer with Files can be used if the Trace should run for a certain duration i.e. an issue is reproduced but a “rolling” Trace should capture the issue. My official “day” Job is 3rd Level support at Poly, but I am unable to provide official support via the community.---------------- Notice: This community forum is not an official Poly support resource, thus responses from Poly employees, partners, and customers alike are best-effort in attempts to share learned knowledge.

If you need immediate and/or official assistance please open a service ticket through your proper support channels. Please also ensure you always check the VoIP, Video Endpoint, Skype for Business, PSTN or RPM FAQ's. Many people think the HTTP filter is enough, but you end up missing the handshake and termination packets.

FoxNews.com is a good one because they have a very large site that loads a lot of information and (at the time of writing this) they have not switched to HTTPS, sadly. You’ll notice that all the packets in the list show HTTP for the protocol.

You’re missing the setup handshakes and termination TCP packets. If you want to filter for all HTTP traffic exchanged with a specific you can use the “and” operator.

If, for example, you wanted to see all HTTP traffic related to a site at exist you could use the following filter: If you want to dig into your HTTP traffic you can filter for things like GET, PUT, POST, DELETE, HEAD, OPTIONS, CONNECT, and TRACE.

If you really want to put the whole picture together when troubleshooting problems with accessing websites you have to take a multi-pronged approach. Unlike other tools, NPM is ready to out of the box with most common makes and models of networking equipment.

Related Videos

Sources
1 winaero.com - https://winaero.com/change-user-agent-opera/
2 winaero.com - https://winaero.com/change-user-agent-firefox/
3 www.howtogeek.com - https://www.howtogeek.com/113439/how-to-change-your-browsers-user-agent-without-installing-any-extensions/
4 www.bettertechtips.com - https://www.bettertechtips.com/how-to/change-user-agent-opera/
5 passivetech.com - https://passivetech.com/2020/04/28/how-to-change-your-browsers-user-agent-and-trick-websites/
6 www.zytrax.com - https://www.zytrax.com/tech/web/change-ua.html
7 www.howtogeek.com - https://www.howtogeek.com/howto/18519/how-to-change-the-user-agent-string-in-firefox/
8 www.tricksway.com - https://www.tricksway.com/changing-user-agent-in-firefox/
9 www.lostsaloon.com - https://www.lostsaloon.com/technology/how-to-change-user-agent-string-in-mozilla-firefox/
10 www.ubergizmo.com - https://www.ubergizmo.com/how-to/change-browser-user-agent/