Wireshark Wireshark - 2.9 User Guide

Wireshark User’s Guide
Version 2.9.0

Preface

Foreword

Wireshark is one of those programs that many network managers would love to be able to use, but they are often prevented from getting what they would like from Wireshark because of the lack of documentation.
This document is part of an effort by the Wireshark team to improve the usability of Wireshark.

Who should read this document?

The intended audience of this book is anyone using Wireshark.
This book will explain all the basics and also some of the advanced features that Wireshark provides. As Wireshark has become a very complex program since the early days, not every feature of Wireshark may be explained in this book.
This book is not intended to explain network sniffing in general and it will not provide details about specific network protocols. A lot of useful information regarding these topics can be found at the Wireshark Wiki at https://wiki.wireshark.org/.
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 of the 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) users of Wireshark.

Acknowledgements

The authors would like to thank the whole Wireshark team for their assistance. In particular, the authors would like to thank:
• 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.
The authors would also like to thank the following people for their helpful feedback on this document:
• Pat Eyler, for his suggestions on improving the example on generating a backtrace.
• Martin Regner, for his various suggestions and corrections.
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• Graeme Hewson, for a lot of grammatical corrections.
The authors would like to acknowledge those man page and README authors for the Wireshark project from who sections of this document borrow heavily:
• Scott Renfro from whose mergecap man page mergecap: Merging multiple capture files into one
is derived.
• Ashok Narayanan from whose text2pcap man page text2pcap: Converting ASCII hexdumps to
network captures is derived.

About this document

This book was originally developed by Richard Sharpe with funds provided from the Wireshark Fund. It was updated by Ed Warnicke and more recently redesigned and updated by Ulf Lamping.
It was originally written in DocBook/XML and converted to AsciiDoc by Gerald Combs.

Where to get the latest copy of this document?

The latest copy of this documentation can always be found at https://www.wireshark.org/docs/.

Providing feedback about this document

Should you have any feedback about this document, please send it to the authors through
wireshark-dev[AT]wireshark.org.

Typographic Conventions

The following table shows the typographic conventions that are used in this guide.
Table 1. Typographic Conventions
Style Description Example
Italic File names, folder names, and extensions C:\Development\wireshark.
Monospace
Bold Monospace
Commands, flags, and environment variables
Commands that should be run by the user
CMake’s -G option.
Run cmake -G Ninja ...
[Button] Dialog and window buttons Press [Launch] to go to the Moon.
Key
Menu Menu item
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Keyboard shortcut Press Ctrl+Down to move to the next
packet.
Select Go Next Packet to move to the next packet.
Admonitions
Important and notable items are marked as follows:
This is a warning
WARNING
NOTE
This is a tip
TIP
Tips are helpful for your everyday work using Wireshark.
You should pay attention to a warning, otherwise data loss might occur.
This is a note
A note will point you to common mistakes and things that might not be obvious.
Shell Prompt and Source Code Examples
Bourne shell, normal user
$ # This is a comment $ git config --global log.abbrevcommit true
Bourne shell, root user
# # This is a comment # ninja install
Command Prompt (cmd.exe)
>rem This is a comment >cd C:\Development
PowerShell
PS$># This is a comment PS$>choco list -l
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C Source Code
#include "config.h"
/* This method dissects foos */ static int dissect_foo_message(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_) { Ê /* TODO: implement your dissecting code */ Ê return tvb_captured_length(tvb); }
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Introduction

What is Wireshark?

Wireshark is a network packet analyzer. A network packet analyzer will try to capture network packets and tries to display that packet data as detailed as possible.
You could think of a network packet analyzer as a measuring device used to examine what’s going on inside a network cable, just like a voltmeter is used by an electrician to examine what’s going on inside an electric cable (but at a higher level, of course).
In the past, such tools were either very expensive, proprietary, or both. However, with the advent of Wireshark, all that has changed.
Wireshark is perhaps one of the best open source packet analyzers available today.
Some intended purposes
Here are some examples people use Wireshark for:
• Network administrators use it to troubleshoot network problems
• Network security engineers use it to examine security problems
• QA engineers use it to verify network applications
• Developers use it to debug protocol implementations
• People use it to learn network protocol internals
Beside these examples Wireshark can be helpful in many other situations too.
Features
The following are some of the many features Wireshark provides:
• Available for UNIX and Windows.
Capture live packet data from a network interface.
Open files containing packet data captured with tcpdump/WinDump, Wireshark, and a number of other packet capture programs.
Import packets from text files containing hex dumps of packet data.
• Display packets with very detailed protocol information.
Save packet data captured.
Export some or all packets in a number of capture file formats.
Filter packets on many criteria.
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Search for packets on many criteria.
Colorize packet display based on filters.
• Create various statistics.
• …and a lot more!
However, to really appreciate its power you have to start using it.
Wireshark captures packets and lets you examine their contents. shows Wireshark having captured
some packets and waiting for you to examine them.
Figure 1. Wireshark captures packets and lets you examine their contents.
Live capture from many different network media
Wireshark can capture traffic from many different network media types - and despite its name ­including wireless LAN as well. Which media types are supported, depends on many things like the operating system you are using. An overview of the supported media types can be found at
https://wiki.wireshark.org/CaptureSetup/NetworkMedia.
Import files from many other capture programs
Wireshark can open packets captured from a large number of other capture programs. For a list of input formats see Input File Formats.
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Export files for many other capture programs
Wireshark can save packets captured in a large number of formats of other capture programs. For a list of output formats see Output File Formats.
Many protocol dissectors
There are protocol dissectors (or decoders, as they are known in other products) for a great many protocols: see Protocols and Protocol Fields.
Open Source Software
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!
What Wireshark is not
Here are some things Wireshark does not provide:
• 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 will not manipulate things on the network, it will only “measure” things from it. Wireshark doesn’t send packets on the network or do other active things (except for name resolutions, but even that can be disabled).

System Requirements

The amount of resources Wireshark needs depends on your environment and on the size of the capture file you are analyzing. 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.
Busy networks mean large captures
Working with a busy network can easily produce huge capture files. Capturing on a
NOTE
gigabit or even 100 megabit network can produce hundreds of megabytes of capture data in a short time. A fast processor, lots of memory and disk space is always a good idea.
If Wireshark runs out of memory it will crash. See https://wiki.wireshark.org/KnownBugs/
OutOfMemory for details and workarounds.
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Although Wireshark captures packets using a separate process the main interface is single­threaded and won’t benefit much from multi-core systems.
Microsoft Windows
• The current version of Wireshark should support any version of Windows that is still within its
extended support lifetime. At the time of writing this includes Windows 10, 8, 7, Vista, Server
2016, Server 2012 R2, Server 2012, Server 2008 R2, and Server 2008.
• Any modern 64-bit AMD64/x86-64 or 32-bit x86 processor.
• 400 MB available RAM. Larger capture files require more RAM.
• 300 MB available disk space. Capture files require additional disk space.
• 1024 × 768 (1280 × 1024 or higher recommended) resolution with at least 16-bit color. 8-bit color should work but user experience will be degraded. Power users will find multiple monitors useful.
• A supported network card for capturing
Ethernet. Any card supported by Windows should work. See the wiki pages on Ethernet
capture and offloading for issues that may affect your environment.
802.11. See the Wireshark wiki page. Capturing raw 802.11 information may be difficult
without special equipment.
Other media. See https://wiki.wireshark.org/CaptureSetup/NetworkMedia.
Older versions of Windows which are outside Microsoft’s extended lifecycle support window are no longer supported. 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 1.12 was the last release branch to support Windows Server 2003. Wireshark 1.10 was the last branch to officially support Windows XP. See the Wireshark release lifecycle page for more details.
UNIX / Linux
Wireshark runs on most UNIX and UNIX-like platforms including macOS and Linux. The system requirements should be comparable to the Windows values listed above.
Binary packages are available for most Unices and Linux distributions including the following platforms:
• Apple macOS
• Debian GNU/Linux
• FreeBSD
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• Gentoo Linux
• HP-UX
• Mandriva Linux
• NetBSD
• OpenPKG
• Red Hat Enterprise/Fedora Linux
• Sun Solaris/i386
• Sun Solaris/SPARC
• Canonical Ubuntu
If a binary package is not available for your platform you can download the source and try to build it. Please report your experiences to wireshark-dev[AT]wireshark.org.

Where to get Wireshark

You can get the latest copy of the program from the Wireshark website at
https://www.wireshark.org/download.html. The download page should automatically highlight the
appropriate download for your platform and direct you to the nearest mirror. Official Windows and macOS installers are signed by the Wireshark Foundation.
A new Wireshark version typically becomes available each month or two.
If you want to be notified about new Wireshark releases you should subscribe to the wireshark­announce mailing list. You will find more details in Mailing Lists.

A brief history of Wireshark

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.
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. So he started contributing dissectors and contributing patches.
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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 Sharkfest.
In 2015 Wireshark 2.0 was released, which featured a new user interface.

Development and maintenance of Wireshark

Wireshark was initially developed by Gerald Combs. Ongoing development and maintenance of Wireshark is handled by the Wireshark team, a loose group of individuals who fix bugs and provide new functionality.
There have also been a large number of people who have contributed protocol dissectors to Wireshark, and it is expected that this will continue. You can find a list of the people who have contributed code to Wireshark by checking the about dialog box of Wireshark, or at the authors page on the Wireshark web site.
Wireshark is an open source software project, and is released under the GNU General Public
License (GPL) version 2. All source code is freely available under the GPL. You are welcome to
modify Wireshark to suit your own needs, and it would be appreciated if you contribute your improvements back to the Wireshark team.
You gain three benefits by contributing your improvements back to the community:
1. Other people who find your contributions useful will appreciate them, and you will know that you have helped people in the same way that the developers of Wireshark have helped people.
2. The developers of Wireshark might improve your changes even more, as there’s always room for improvement. Or they may implement some advanced things on top of your code, which can be useful for yourself too.
3. The maintainers and developers of Wireshark will maintain your code as well, fixing it when API changes or other changes are made, and generally keeping it in tune with what is happening with Wireshark. So if Wireshark is updated (which is done often), you can get a new Wireshark version from the website and your changes will already be included without any effort for you.
The Wireshark source code and binary kits for some platforms are all available on the download page of the Wireshark website: https://www.wireshark.org/download.html.
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Reporting problems and getting help

If you have problems or need help with Wireshark there are several places that may be of interest to you (well, besides this guide of course).
Website
You will find lots of useful information on the Wireshark homepage at https://www.wireshark.org/.
Wiki
The Wireshark Wiki at https://wiki.wireshark.org/ provides a wide range of information related to Wireshark and packet capture in general. You will find a lot of information not part of this user’s guide. For example, there is an explanation how to capture on a switched network, an ongoing effort to build a protocol reference and a lot 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 by simply using your web browser.
Q&A Site
The Wireshark Q&A site at https://ask.wireshark.org/ offers a resource where questions and answers come together. You have the option to search what questions were asked before and what answers were given by people who knew about the issue. Answers are graded, so you can pick out the best ones easily. If your question hasn’t been discussed before you can post one yourself.
FAQ
The Frequently Asked Questions lists often asked questions and their corresponding answers.
Read the FAQ
NOTE
You will find the FAQ inside Wireshark by clicking the menu item Help/Contents and selecting the FAQ page in the dialog shown.
Before sending any mail to the mailing lists below, be sure to read the FAQ. It will often answer any questions you might have. This will save yourself and others a lot of time. Keep in mind that a lot of people are subscribed to the mailing lists.
An online version is available at the Wireshark website at https://www.wireshark.org/faq.html. You might prefer this online version, as it’s typically more up to date and the HTML format is easier to use.
Mailing Lists
There are several mailing lists of specific Wireshark topics available:
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wireshark-announce
This mailing list will inform you about new program releases, which usually appear about every 4-8 weeks.
wireshark-users
This list is for users of Wireshark. People post questions about building and using Wireshark, others (hopefully) provide answers.
wireshark-dev
This list is for Wireshark developers. If you want to start developing a protocol dissector, join this list.
You can subscribe to each of these lists from the Wireshark web site: https://www.wireshark.org/
lists/. From there, you can choose which mailing list you want to subscribe to by clicking on the
Subscribe/Unsubscribe/Options button under the title of the relevant list. The links to the archives are included on that page as well.
The lists are archived
TIP
You can search in the list archives to see if someone asked the same question some time before and maybe already got an answer. That way you don’t have to wait until someone answers your question.
Reporting Problems
NOTE
When reporting problems with Wireshark please supply the following information:
1. The version number of Wireshark and the dependent libraries linked with it, such as Qt or GLib. You can obtain this from Wireshark’s about box or the command wireshark -v.
2. Information about the platform you run Wireshark on.
3. A detailed description of your problem.
4. If you get an error/warning message, copy the text of that message (and also a few lines before and after it, if there are some) so others may find the place where things go wrong. Please don’t give something like: “I get a warning while doing x” as this won’t give a good idea where to look.
Before reporting any problems, please make sure you have installed the latest version of Wireshark.
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NOTE
Don’t send large files
Do not send large files (> 1 MB) to the mailing lists. Just place a note that further data is available on request. Large files will only annoy a lot of people on the list who are not interested in your specific problem. If required you will be asked for further data by the persons who really can help you.
Don’t send confidential information!
WARNING
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 (PII).
Reporting Crashes on UNIX/Linux platforms
When reporting crashes with Wireshark it is helpful if you supply the traceback information along with the information mentioned in “Reporting Problems”.
You can obtain this traceback information with the following commands on UNIX or Linux (note the backticks):
$ gdb `whereis wireshark | cut -f2 -d: | cut -d' ' -f2` core >& backtrace.txt backtrace ^D
If you do not have gdb available, you will have to check out your operating system’s debugger.
Mail backtrace.txt to wireshark-dev[AT]wireshark.org.
Reporting Crashes on Windows platforms
The Windows distributions don’t contain the symbol files (.pdb) because they are very large. You can download them separately at https://www.wireshark.org/download/win32/all-versions/ and
https://www.wireshark.org/download/win64/all-versions/ .
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Building and Installing Wireshark

Introduction

As with all things there must be a beginning and so it is with Wireshark. To use Wireshark you must first install it. If you are running Windows or macOS you can download an official release at
https://www.wireshark.org/download.html, install it, and skip the rest of this chapter.
If you are running another operating system such as Linux or FreeBSD you might want to install from source. Several Linux distributions offer Wireshark packages but they commonly ship out-of­date versions. No other versions of UNIX ship Wireshark so far. For that reason, you will need to know where to get the latest version of Wireshark and how to install it.
This chapter shows you how to obtain source and binary packages and how to build Wireshark from source should you choose to do so.
The following are the general steps you would use:
1. Download the relevant package for your needs, e.g. source or binary distribution.
2. Compile the source into a binary if needed. This may involve building and/or installing other necessary packages.
3. Install the binaries into their final destinations.

Obtaining the source and binary distributions

You can obtain both source and binary distributions from the Wireshark web site:
https://www.wireshark.org/download.html. Select the download link and then select the desired
binary or source package.
Download all required files
If you are building Wireshark from source you will In general, unless you have
NOTE
Once you have downloaded the relevant files, you can go on to the next step.
already downloaded Wireshark before, you will most likely need to download several source packages if you are building Wireshark from source. This is covered in more detail below.

Installing Wireshark under Windows

Windows installer names contain the platform and version. For example, Wireshark-win64-
2.9.0.exe installs Wireshark 2.9.0 for 64-bit Windows. The Wireshark installer includes WinPcap which is required for packet capture.
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Simply download the Wireshark installer from https://www.wireshark.org/download.html and execute it. Official packages are signed by the Wireshark Foundation. You can choose to install several optional components and select the location of the installed package. The default settings are recommended for most users.
Installation Components
On the Choose Components page of the installer you can select from the following:
Wireshark - The network protocol analyzer that we all know and mostly love.
TShark - A command-line network protocol analyzer. If you haven’t tried it you should.
Plugins & Extensions - Extras for the Wireshark and TShark dissection engines
Dissector Plugins - Plugins with some extended dissections.
Tree Statistics Plugins - Extended statistics.
Mate - Meta Analysis and Tracing Engine - User configurable extension(s) of the display
filter engine, see MATE for details.
SNMP MIBs - SNMP MIBs for a more detailed SNMP dissection.
Tools - Additional command line tools to work with capture files
Editcap - Reads a capture file and writes some or all of the packets into another capture file.
Text2Pcap - Reads in an ASCII hex dump and writes the data into a pcap capture file.
Reordercap - Reorders a capture file by timestamp.
Mergecap - Combines multiple saved capture files into a single output file.
Capinfos - Provides information on capture files.
Rawshark - Raw packet filter.
User’s Guide - Local installation of the User’s Guide. The Help buttons on most dialogs will
require an internet connection to show help pages if the User’s Guide is not installed locally.
Additional Tasks
Start Menu Shortcuts - Add some start menu shortcuts.
Desktop Icon - Add a Wireshark icon to the desktop.
Quick Launch Icon - add a Wireshark icon to the Explorer quick launch toolbar.
Associate file extensions to Wireshark - Associate standard network trace files to Wireshark.
Install Location
By default Wireshark installs into %ProgramFiles%\Wireshark on 32-bit Windows and
%ProgramFiles64%\Wireshark on 64-bit Windows. This expands to C:\Program Files\Wireshark on
most systems.
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Installing WinPcap
The Wireshark installer contains the latest WinPcap installer.
If you don’t have WinPcap installed you won’t be able to capture live network traffic but you will still be able to open saved capture files. By default the latest version of WinPcap will be installed. If you don’t wish to do this or if you wish to reinstall WinPcap you can check the Install WinPcap box as needed.
For more information about WinPcap see https://www.winpcap.org/ and https://wiki.wireshark.org/
WinPcap.
Windows installer command line options
For special cases, there are some command line parameters available:
/S runs the installer or uninstaller silently with default values. The silent installer will not
install WinPCap.
/desktopicon installation of the desktop icon, =yes - force installation, =no - don’t install,
otherwise use default settings. This option can be useful for a silent installer.
/quicklaunchicon installation of the quick launch icon, =yes - force installation, =no - don’t install,
otherwise use default settings.
/D sets the default installation directory ($INSTDIR), overriding InstallDir and InstallDirRegKey.
It must be the last parameter used in the command line and must not contain any quotes even if the path contains spaces.
/NCRC disables the CRC check. We recommend against using this flag.
Example:
> Wireshark-win64-wireshark-2.0.5.exe /NCRC /S /desktopicon=yes /quicklaunchicon=no /D=C:\Program Files\Foo
Running the installer without any parameters shows the normal interactive installer.
Manual WinPcap Installation
As mentioned above, the Wireshark installer takes care of installing WinPcap. The following is only necessary if you want to use a different version than the one included in the Wireshark installer, e.g. because a new WinPcap version was released.
Additional WinPcap versions (including newer alpha or beta releases) can be downloaded from the main WinPcap site at https://www.winpcap.org/. The Installer for Windows supports modern Windows operating systems.
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Update Wireshark
By default the offical 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 subcribe to the wireshark-announce mailing list. See Mailing Lists for details on subscribing to this list.
New versions of Wireshark are usually released every four to six weeks. Updating Wireshark is done the same way as installing it. Simply download and start the installer exe. A reboot is usually not required and all your personal settings remain unchanged.
Update WinPcap
New versions of WinPcap are less frequently available. You will find WinPcap update instructions the WinPcap web site at https://www.winpcap.org/. You may have to reboot your machine after installing a new WinPcap version.
Uninstall Wireshark
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 WinPcap. WinPcap is left installed by default in case other programs need it.
Uninstall WinPcap
You can uninstall WinPcap independently of Wireshark using the WinPcap entry in the Programs and Features control panel. Remember that if you uninstall WinPcap you won’t be able to capture
anything with Wireshark.

Installing Wireshark under macOS

The official macOS packages are distributed as disk images (.dmg) containing the application installer. To install Wireshark simply open the disk image and run the enclosed installer.
The installer package includes Wireshark, its related command line utilities, and a launch daemon that adjusts capture permissions at system startup. See the included Read me first file for more details.

Building Wireshark from source under UNIX

Building Wireshark requires the proper build environment including a compiler and many supporting libraries. See the Developer’s Guide at https://www.wireshark.org/docs/ for more
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information.
Use the following general steps to build Wireshark from source under UNIX or Linux:
1. Unpack the source from its compressed tar file. If you are using Linux or your version of UNIX uses GNU tar you can use the following command:
$ tar xaf wireshark-2.9.0.tar.xz
In other cases you will have to use the following commands:
$ xz -d wireshark-2.9.0.tar.xz $ tar xf wireshark-2.9.0.tar
2. Create a directory to build Wireshark in and change to it.
$ mkdir build $ cd build
3. Configure your source so it will build correctly for your version of UNIX. You can do this with the following command:
$ cmake ../wireshark-2.9.0
If this step fails you will have to look into the logs and rectify the problems, then rerun cmake. Troubleshooting hints are provided in Troubleshooting during the build and install on Unix.
4. Build the sources.
$ make
Once you have build Wireshark with make above, you should be able to run it by entering
run/wireshark.
5. Install the software in its final destination.
$ make install
Once you have installed Wireshark with make install above, you should be able to run it by entering wireshark.
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Installing the binaries under UNIX

In general installing the binary under your version of UNIX will be specific to the installation methods used with your version of UNIX. For example, under AIX, you would use smit to install the Wireshark binary package, while under Tru64 UNIX (formerly Digital UNIX) you would use setld.
Installing from RPMs under Red Hat and alike
Building RPMs from Wireshark’s source code results in several packages (most distributions follow the same system):
• The wireshark package contains the core Wireshark libraries and command-line tools.
• The wireshark or wireshark-qt package contains the Qt-based GUI.
Many distributions use yum or a similar package management tool to make installation of software (including its dependencies) easier. If your distribution uses yum, use the following command to install Wireshark together with the Qt GUI:
yum install wireshark wireshark-qt
If you’ve built your own RPMs from the Wireshark sources you can install them by running, for example:
rpm -ivh wireshark-2.0.0-1.x86_64.rpm wireshark-qt-2.0.0-1.x86_64.rpm
If the above command fails because of missing dependencies, install the dependencies first, and then retry the step above.
Installing from debs under Debian, Ubuntu and other Debian derivatives
If you can just install from the repository then use
$ aptitude install wireshark
Aptitude should take care of all of the dependency issues for you.
Use the following command to install downloaded Wireshark debs under Debian:
$ dpkg -i wireshark-common_2.0.5.0-1_i386.deb wireshark_wireshark-2.0.5.0-1_i386.deb
dpkg doesn’t take care of all dependencies, but reports what’s missing.
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Capturing requires privileges
NOTE
By installing Wireshark packages non-root users won’t gain rights automatically to capture packets. To allow non-root users to capture packets follow the procedure described in /usr/share/doc/wireshark-common/README.Debian
Installing from portage under Gentoo Linux
Use the following command to install Wireshark under Gentoo Linux with all of the extra features:
$ USE="c-ares ipv6 snmp ssl kerberos threads selinux" emerge wireshark
Installing from packages under FreeBSD
Use the following command to install Wireshark under FreeBSD:
$ pkg_add -r wireshark
pkg_add should take care of all of the dependency issues for you.

Troubleshooting during the build and install on Unix

A number of errors can occur during the build and installation process. Some hints on solving these are provided here.
If the cmake stage fails you will need to find out why. You can check the file CMakeOutput.log and
CMakeError.log in the build directory to find out what failed. The last few lines of this file should
help in determining the problem.
The standard problems are that you do not have a required development package on your system or that the development package isn’t new enough. Note that installing a library package isn’t enough. You need to install its development package as well. cmake will also fail if you do not have libpcap (at least the required include files) on your system.
If you cannot determine what the problems are, send an email to the wireshark-dev mailing list explaining your problem. Include the output from cmake and anything else you think is relevant such as a trace of the make stage.

Building from source under Windows

We strongly recommended that you use the binary installer for Windows unless you want to start developing Wireshark on the Windows platform.
20
For further information how to build Wireshark for Windows from the sources see the Developer’s Guide at https://www.wireshark.org/docs/.
You may also want to have a look at the Development Wiki (https://wiki.wireshark.org/
Development) for the latest available development documentation.
21

User Interface

Introduction

By now you have installed Wireshark and are most likely keen to get started capturing your first packets. In the next chapters we will explore:
• How the Wireshark user interface works
• How to capture packets in Wireshark
• How to view packets in Wireshark
• How to filter packets in Wireshark
• … and many other things!

Start Wireshark

You can start Wireshark from your shell or window manager.
Power user tip
TIP
In the following chapters a lot of screenshots from Wireshark will be shown. As Wireshark runs on many different platforms with many different window managers, different styles applied and there are different versions of the underlying GUI toolkit used, your screen might look different from the provided screenshots. But as there are no real differences in functionality these screenshots should still be well understandable.
When starting Wireshark it’s possible to specify optional settings using the command line. See Start Wireshark from the command line for details.

The Main window

Let’s look at Wireshark’s user interface. 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).
22
Figure 2. The Main window
Wireshark’s main window consists of parts that are commonly known from many other GUI programs.
1. The menu (see The Menu) is used to start actions.
2. The main toolbar (see The “Main” Toolbar) provides quick access to frequently used items from the menu.
3. The filter toolbar (see The “Filter” Toolbar) provides a way to directly manipulate the currently used display filter (see Filtering packets while viewing).
4. The packet list pane (see The “Packet List” Pane) displays a summary of each packet captured. By clicking on packets in this pane you control what is displayed in the other two panes.
5. The packet details pane (see The “Packet Details” Pane) displays the packet selected in the packet list pane in more detail.
6. The packet bytes pane (see The “Packet Bytes” Pane) displays the data from the packet selected in the packet list pane, and highlights the field selected in the packet details pane.
7. The statusbar (see The Statusbar) shows some detailed information about the current program state and the captured data.
TIP
The layout of the main window can be customized by changing preference settings. See Preferences for details!
23
Main Window Navigation
Packet list and detail navigation can be done entirely from the keyboard. Keyboard Navigation shows a list of keystrokes that will let you quickly move around a capture file. See Go menu items for additional navigation keystrokes.
Table 2. Keyboard Navigation
Accelerator Description
Tab or Shift+Tab Move between screen elements, e.g. from the toolbars to the packet list to
the packet detail.
Ctrl+ or F8 Move to the next packet, even if the packet list isn’t focused.
Ctrl+ or F7 Move to the previous packet, even if the packet list isn’t focused.
Ctrl+. Move to the next packet of the conversation (TCP, UDP or IP).
Ctrl+, Move to the previous packet of the conversation (TCP, UDP or IP).
Alt+ or Option+
(macOS)
Alt+ or Option+
(macOS)
Shift+ In the packet detail, opens the selected tree item and all of its subtrees.
Ctrl+ In the packet detail, opens all tree items.
Ctrl+ In the packet detail, closes all tree items.
Move to the next packet or detail item.
Move to the previous packet or detail item.
Move to the next packet in the selection history.
Move to the previous packet in the selection history.
In the packet detail, closes the selected tree item. If it’s already closed, jumps to the parent node.
In the packet detail, opens the selected tree item.
Backspace
Return or Enter In the packet detail, toggles the selected tree item.
Help About Wireshark Keyboard Shortcuts will show a list of all shortcuts in the main window. Additionally, typing anywhere in the main window will start filling in a display filter.
In the packet detail, jumps to the parent node.

The Menu

Wireshark’s main menu is located either at the top of the main window (Windows, Linux) or at the top of your main screen (macOS). An example is shown in The Menu.
Some menu items will be disabled (greyed out) if the corresponding feature isn’t
NOTE
24
available. For example, you cannot save a capture file if you haven’t captured or loaded any packets.
Figure 3. The Menu
The main menu contains the following items:
File
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. See The “File” menu.
Edit
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). See The “Edit” Menu.
View
This menu controls the display of the captured data, including colorization of packets, zooming the font, showing a packet in a separate window, expanding and collapsing trees in packet details, …. See The “View” Menu.
Go
This menu contains items to go to a specific packet. See The “Go” Menu.
Capture
This menu allows you to start and stop captures and to edit capture filters. See The “Capture”
menu.
Analyze
This menu contains items to manipulate display filters, enable or disable the dissection of protocols, configure user specified decodes and follow a TCP stream. See The “Analyze” Menu.
Statistics
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. See The
“Statistics” Menu.
Telephony
This menu contains items to display various telephony related statistic windows, including a media analysis, flow diagrams, display protocol hierarchy statistics and much more. See The
“Telephony” Menu.
Wireless
The items in this menu show Bluetooth and IEEE 802.11 wireless statistics.
Tools
This menu contains various tools available in Wireshark, such as creating Firewall ACL Rules.
25
See The “Tools” Menu.
Help
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 of the webpages, and the usual about dialog. See The “Help” Menu.
Each of these menu items is described in more detail in the sections that follow.
Shortcuts make life easier
TIP
Most common menu items have keyboard shortcuts. For example, you can press the Control (or Strg in German) and the K keys together to open the “Capture Options” dialog.

The “File” menu

The Wireshark file menu contains the fields shown in File menu items.
Figure 4. The “File” Menu
Table 3. File menu items
26
Menu Item Accelerator Description
Open… Ctrl+O This shows the file open dialog box that allows
you to load a capture file for viewing. It is discussed in more detail in The “Open Capture
File” dialog box.
Open Recent This lets you open recently opened capture files.
Clicking on one of the submenu items will open the corresponding capture file directly.
Merge… This menu item lets you merge a capture file
into the currently loaded one. It is discussed in more detail in Merging capture files.
Import from Hex Dump… 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 Import
hex dump.
Close Ctrl+W This menu item closes the current capture. If
you haven’t saved the capture, you will be asked to do so first (this can be disabled by a preference setting).
Save Ctrl+S This menu item saves the current capture. If you
have not set a default capture file name (perhaps with the -w <capfile> option), Wireshark pops up the Save Capture File As dialog box (which is discussed further in The
“Save Capture File As” dialog box).
If you have already saved the current capture, this menu item will be greyed out.
You cannot save a live capture while the capture is in progress. You must stop the capture in order to save.
Save As… Shift+Ctrl+S This menu item allows you to save the current
capture file to whatever file you would like. It pops up the Save Capture File As dialog box (which is discussed further in The “Save Capture
File As” dialog box).
File Set List Files
This menu item allows you to show a list of files in a file set. It pops up the Wireshark List File Set dialog box (which is discussed further in File
Sets).
27
Menu Item Accelerator Description
File Set Next File
File Set Previous File
Export Specified Packets… This menu item allows you to export all (or
Export Packet Dissections…
Export Objects These menu items allow you to export captured
Ctrl+H These menu items allow you to export the
If the currently loaded file is part of a file set, jump to the next file in the set. If it isn’t part of a file set or just the last file in that set, this item is greyed out.
If the currently loaded file is part of a file set, jump to the previous file in the set. If it isn’t part of a file set or just the first file in that set, this item is greyed out.
some) of the packets in the capture file to file. It pops up the Wireshark Export dialog box (which is discussed further in Exporting data).
currently selected bytes in the packet bytes pane to a text file file in a number of formats including plain, CSV, and XML. It is discussed further in The “Export selected packet bytes”
dialog box.
DICOM, HTTP, IMF, SMB, or TFTP objects into local files. It pops up a corresponding object list (which is discussed further in The “Export
Objects” dialog box)
Print… Ctrl+P This menu item allows you to print all (or some)
of the packets in the capture file. It pops up the Wireshark Print dialog box (which is discussed further in Printing packets).
Quit Ctrl+Q This menu item allows you to quit from
Wireshark. Wireshark will ask to save your capture file if you haven’t previously saved it (this can be disabled by a preference setting).

The “Edit” Menu

The Wireshark Edit menu contains the fields shown in Edit menu items.
28
Figure 5. The “Edit” Menu
Table 4. Edit menu items
Menu Item Accelerator Description
Copy These menu items will copy the packet list,
packet detail, or properties of the currently selected packet to the clipboard.
Find Packet… Ctrl+F This menu item brings up a toolbar that allows
you to find a packet by many criteria. There is further information on finding packets in
Finding packets.
Find Next Ctrl+N This menu item tries to find the next packet
matching the settings from “Find Packet…”.
Find Previous Ctrl+B This menu item tries to find the previous packet
matching the settings from “Find Packet…”.
Mark/Unmark Packet Ctrl+M This menu item marks the currently selected
packet. See Marking packets for details.
Mark All Displayed Packets Shift+Ctrl+M This menu item marks all displayed packets.
Unmark All Displayed
Ctrl+Alt+M This menu item unmarks all displayed packets.
Packets
Next Mark Shift+Alt+N Find the next marked packet.
Previous Mark Shift+Alt+B Find the previous marked packet.
29
Menu Item Accelerator Description
Ignore/Unignore Packet Ctrl+D This menu item marks the currently selected
packet as ignored. See Ignoring packets for details.
Ignore All Displayed Shift+Ctrl+D This menu item marks all displayed packets as
ignored.
Unignore All Displayed Ctrl+Alt+D This menu item unmarks all ignored packets.
Set/Unset Time Reference Ctrl+T This menu item set a time reference on the
currently selected packet. See Packet time
referencing for more information about the time
referenced packets.
Unset All Time References Ctrl+Alt+T This menu item removes all time references on
the packets.
Next Time Reference Ctrl+Alt+N This menu item tries to find the next time
referenced packet.
Previous Time Reference Ctrl+Alt+B This menu item tries to find the previous time
referenced packet.
Time Shift Ctrl+Shift+T This will show the Time Shift dialog, which
allows you to adjust the timestamps of some or all packets.
Packet Comment… This will let you add a comment to a single
packet. Note that the ability to save packet comments depends on your file format. E.g. pcapng supports comments, pcap does not.
Capture Comment… This will let you add a capture comment. Note
that the ability to save capture comments depends on your file format. E.g. pcapng supports comments, pcap does not.
Configuration Profiles… Shift+Ctrl+A This menu item brings up a dialog box for
handling configuration profiles. More detail is provided in Configuration Profiles.
Preferences… Shift+Ctrl+P or
Cmd+, (macOS)
This menu item brings up a dialog box that allows you to set preferences for many parameters that control Wireshark. You can also save your preferences so Wireshark will use them the next time you start it. More detail is provided in Preferences.

The “View” Menu

The Wireshark View menu contains the fields shown in View menu items.
30
Figure 6. The “View” Menu
Table 5. View menu items
Menu Item Accelerator Description
Main Toolbar This menu item hides or shows the main toolbar,
see The “Main” Toolbar.
Filter Toolbar This menu item hides or shows the filter toolbar,
see The “Filter” Toolbar.
Wireless Toolbar This menu item hides or shows the wireless
toolbar. May not be present on some platforms.
Statusbar This menu item hides or shows the statusbar,
see The Statusbar.
Packet List This menu item hides or shows the packet list
pane, see The “Packet List” Pane.
Packet Details This menu item hides or shows the packet
details pane, see The “Packet Details” Pane.
Packet Bytes This menu item hides or shows the packet bytes
pane, see The “Packet Bytes” Pane.
31
Menu Item Accelerator Description
Time Display Format Date and Time of Day: 1970-01-01 01:02:03.123456
Time Display Format Time of Day: 01:02:03.123456
Time Display Format Seconds Since Epoch (1970­01-01): 1234567890.123456
Time Display Format Seconds Since Beginning of Capture: 123.123456
Selecting this tells Wireshark to display the time stamps in date and time of day format, see Time
display formats and time references.
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 time of day format, see Time display
formats and time references.
Selecting this tells Wireshark to display time stamps in seconds since 1970-01-01 00:00:00, see
Time display formats and time references.
Selecting this tells Wireshark to display time stamps in seconds since beginning of capture format, see Time display formats and time
references.
Time Display Format Seconds Since Previous Captured Packet: 1.123456
Time Display Format Seconds Since Previous Displayed Packet: 1.123456
Time Display Format Automatic (File Format Precision)
Time Display Format Seconds: 0
Time Display Format … seconds: 0….
Selecting this tells Wireshark to display time stamps in seconds since previous captured packet format, see Time display formats and
time references.
Selecting this tells Wireshark to display time stamps in seconds since previous displayed packet format, see Time display formats and
time references.
Selecting this tells Wireshark to display time stamps with the precision given by the capture file format used, see Time display formats and
time references.
The fields “Automatic”, “Seconds” and “… seconds” are mutually exclusive.
Selecting this tells Wireshark to display time stamps with a precision of one second, see Time
display formats and time references.
Selecting this tells Wireshark to display time stamps with a precision of one second, decisecond, centisecond, millisecond, microsecond or nanosecond, see Time display
formats and time references.
32
Menu Item Accelerator Description
Time Display Format Display Seconds with
Selecting this tells Wireshark to display time stamps in seconds, with hours and minutes.
hours and minutes
Name Resolution Resolve Name
Name Resolution Enable for MAC Layer
This item allows you to trigger a name resolve of the current packet only, see Name Resolution.
This item allows you to control whether or not Wireshark translates MAC addresses into names, see Name Resolution.
Name Resolution Enable for Network Layer
This item allows you to control whether or not Wireshark translates network addresses into names, see Name Resolution.
Name Resolution Enable for Transport Layer
This item allows you to control whether or not Wireshark translates transport addresses into names, see Name Resolution.
Colorize Packet List This item allows you to control whether or not
Wireshark should colorize the packet list.
Enabling colorization will slow down the display of new packets while capturing / loading capture files.
Auto Scroll in Live Capture This item allows you to specify that Wireshark
should scroll the packet list pane as new packets come in, so you are always looking at the last packet. If you do not specify this, Wireshark simply adds new packets onto the end of the list, but does not scroll the packet list pane.
Zoom In Ctrl++ Zoom into the packet data (increase the font
size).
Zoom Out Ctrl+- Zoom out of the packet data (decrease the font
size).
Normal Size Ctrl+= Set zoom level back to 100% (set font size back to
normal).
Resize All Columns Shift+Ctrl+R Resize all column widths so the content will fit
into it.
Resizing may take a significant amount of time, especially if a large capture file is loaded.
Displayed Columns This menu items folds out with a list of all
configured columns. These columns can now be shown or hidden in the packet list.
Expand Subtrees Shift+ This menu item expands the currently selected
subtree in the packet details tree.
33
Menu Item Accelerator Description
Collapse Subtrees Shift+ This menu item collapses the currently selected
subtree in the packet details tree.
Expand All Ctrl+ 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.
Collapse All Ctrl+ This menu item collapses the tree view of all
packets in the capture list.
Colorize Conversation This menu item brings up a submenu that allows
you to color packets in the packet list pane based on the addresses of the currently selected packet. This makes it easy to distinguish packets belonging to different conversations. Packet
colorization.
Colorize Conversation Color 1-10
Colorize Conversation Reset coloring
Colorize Conversation New Coloring Rule…
Coloring Rules… This menu item brings up a dialog box that
Show Packet in New Window
Reload Ctrl+R This menu item allows you to reload the current
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.
allows you to color packets in the packet list pane according to filter expressions you choose. It can be very useful for spotting certain types of packets, see Packet colorization.
This menu item brings up the selected packet in a separate window. The separate window shows only the tree view and byte view panes.
capture file.

The “Go” Menu

The Wireshark Go menu contains the fields shown in Go menu items.
34
Figure 7. The “Go” Menu
Table 6. Go menu items
Menu Item Accelerator Description
Back Alt+ Jump to the recently visited packet in the packet
history, much like the page history in a web browser.
Forward Alt+ Jump to the next visited packet in the packet
history, much like the page history in a web browser.
Go to Packet… Ctrl+G Bring up a window frame that allows you to
specify a packet number, and then goes to that packet. See Go to a specific packet for details.
Go to Corresponding Packet
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.
Previous Packet Ctrl+ Move to the previous packet in the list. This can
be used to move to the previous packet even if the packet list doesn’t have keyboard focus.
Next Packet Ctrl+ Move to the next packet in the list. This can be
used to move to the previous packet even if the packet list doesn’t have keyboard focus.
35
Menu Item Accelerator Description
First Packet Ctrl+Home Jump to the first packet of the capture file.
Last Packet Ctrl+End Jump to the last packet of the capture file.
Previous Packet In Conversation
Next Packet In Conversation
Ctrl+, Move to the previous packet in the current
conversation. This can be used to move to the previous packet even if the packet list doesn’t have keyboard focus.
Ctrl+. Move to the next packet in the current
conversation. This can be used to move to the previous packet even if the packet list doesn’t have keyboard focus.

The “Capture” menu

The Wireshark Capture menu contains the fields shown in Capture menu items.
Figure 8. The “Capture” Menu
Table 7. Capture menu items
36
Menu Item Accelerator Description
Interfaces… Ctrl+I This menu item brings up a dialog box that
shows what’s going on at the network interfaces Wireshark knows of, see The “Capture
Interfaces” dialog box) .
Options… Ctrl+K This menu item brings up the Capture Options
dialog box (discussed further in The “Capture
Options” dialog box) and allows you to start
capturing packets.
Start Ctrl+E Immediately start capturing packets with the
same settings than the last time.
Stop Ctrl+E This menu item stops the currently running
capture, see Stop the running capture) .
Restart Ctrl+R This menu item stops the currently running
capture and starts again with the same options, this is just for convenience.
Capture Filters… This menu item brings up a dialog box that
allows you to create and edit capture filters. You can name filters, and you can save them for future use. More detail on this subject is provided in Defining and saving filters

The “Analyze” Menu

The Wireshark Analyze menu contains the fields shown in Analyze menu items.
37
Figure 9. The “Analyze” Menu
Table 8. Analyze menu items
Menu Item Accelerator Description
Display Filters… This menu item brings up a dialog box that
allows you to create and edit display filters. You can name filters, and you can save them for future use. More detail on this subject is provided in Defining and saving filters
Display Filter Macros… This menu item brings up a dialog box that
allows you to create and edit display filter macros. You can name filter macros, and you can save them for future use. More detail on this subject is provided in Defining and saving filter
macros
Apply as Column This menu item adds the selected protocol item
in the packet details pane as a column to the packet list.
Apply as Filter
38
These menu items will change the current display filter and apply the changed filter 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.
Menu Item Accelerator Description
Prepare a Filter
Enabled Protocols… Shift+Ctrl+E This menu item allows the user to enable/disable
Decode As… This menu item allows the user to force
User Specified Decodes… This menu item allows the user to force
Follow TCP Stream
These menu items will change the current display filter but won’t apply the changed filter. 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.
protocol dissectors, see The “Enabled Protocols”
dialog box
Wireshark to decode certain packets as a particular protocol, see User Specified Decodes
Wireshark to decode certain packets as a particular protocol, see Show User Specified
Decodes
This menu item brings up a separate window and displays all the TCP segments captured that are on the same TCP connection as a selected packet, see Following Protocol Streams
Follow UDP Stream
Follow SSL Stream
Follow HTTP Stream
Expert Info Open a dialog showing some expert information
Conversation Filter
Same functionality as “Follow TCP Stream” but for UDP streams.
Same functionality as “Follow TCP Stream” but for SSL streams. See the wiki page on SSL for instructions on providing SSL keys.
Same functionality as “Follow TCP Stream” but for HTTP streams.
about the captured packets. The amount of information will depend on the protocol and varies from very detailed to non-existent. XXX ­add a new section about this and link from here
In this menu you will find conversation filter for various protocols.

The “Statistics” Menu

The Wireshark Statistics menu contains the fields shown in Statistics menu items.
39
Figure 10. The “Statistics” Menu
All menu items will bring up a new window showing specific statistical information.
Table 9. Statistics menu items
Menu Item Accelerator Description
Capture File Properties Show information about the capture file, see The
“Capture File Properties” Window.
Resolved Addresses See Resolved Addresses
Protocol Hierarchy Display a hierarchical tree of protocol statistics,
see The “Protocol Hierarchy” Window.
Conversations Display a list of conversations (traffic between
two endpoints), see The “Conversations”
Window.
Endpoints Display a list of endpoints (traffic to/from an
address), see The “Endpoints” Window.
Packet Lengths See Packet Lengths
IO Graphs Display user specified graphs (e.g. the number of
packets in the course of time), see The “I/O
Graph” Window.
Service Response Time Display the time between a request and the
corresponding response, see Service Response
Time.
40
Menu Item Accelerator Description
DHCP (BOOTP) See DHCP (BOOTP) Statistics
ONC-RPC Programs See ONC-RPC Programs
29West See 29West
ANCP See ANCP
BACnet See BACnet
Collectd See Collectd
DNS See DNS
Flow Graph See Flow Graph
HART-IP See HART-IP
HPFEEDS See HPFEEDS
HTTP HTTP request/response statistics, see HTTP
Statistics
HTTP2 See HTTP2
Sametime See Sametime
TCP Stream Graphs See TCP Stream Graphs
UDP Multicast Streams See UDP Multicast Graphs
F5 See F5
IPv4 Statistics See IPv4 Statistics
IPv6 Statistics See IPv6 Statistics

The “Telephony” Menu

The Wireshark Telephony menu contains the fields shown in Telephony menu items.
41
Figure 11. The “Telephony” Menu
All menu items will bring up a new window showing specific telephony related statistical information.
Table 10. Telephony menu items
Menu Item Accelerator Description
VoIP Calls… See VoIP Calls
menu:[ANSI] See ANSI
menu:[GSM] See GSM
menu:[IAX2 Stream
See IAX2 Stream Analysis
Analysis]
menu:[ISUP Messages] See ISUP Messages
menu:[LTE] See LTE
menu:[MTP3] See MTP3
menu:[Osmux] See Osmux
menu:[RTP] See RTP Analysis
menu:[RTSP] See RTSP
menu:[SCTP] See SCTP
menu:[SMPP Operations] See SMPP Operations
menu:[UCP Messages] See UCP Messages
42
Menu Item Accelerator Description
menu:[H.225] See H.225
menu:[SIP Flows] See SIP Flows
menu:[SIP Statistics] See SIP Statistics
menu:[WAP-WSP Packet Counter]
See WAP-WSP Packet Counter

The “Tools” Menu

The Wireshark Tools menu contains the fields shown in Tools menu items.
Figure 12. The “Tools” Menu
Table 11. Tools menu items
43
Menu Item Accelerator Description
Firewall ACL Rules This allows you to create command-line ACL
rules for many different firewall products, including Cisco IOS, Linux Netfilter (iptables), OpenBSD pf and Windows Firewall (via netsh). Rules for MAC addresses, IPv4 addresses, TCP and UDP ports, and IPv4+port combinations are supported.
It is assumed that the rules will be applied to an outside interface.
Lua These options allow you to work with the Lua
interpreter optionally build into Wireshark. See the “Lua Support in Wireshark” in the Wireshark Developer’s Guide.

The “Internals” Menu

The Wireshark Internals menu contains the fields shown in Internals menu items.
Figure 13. The “Internals” Menu
Table 12. Internals menu items
44
Menu Item Accelerator Description
Dissector tables This menu item brings up a dialog box showing
the tables with subdissector relationships.
Supported Protocols (slow!)
This menu item brings up a dialog box showing the supported protocols and protocol fields.

The “Help” Menu

The Wireshark Help menu contains the fields shown in Help menu items.
Figure 14. The “Help” Menu
Table 13. Help menu items
Menu Item Accelerator Description
Contents F1 This menu item brings up a basic help system.
Manual Pages
Website This menu item starts a Web browser showing
FAQs This menu item starts a Web browser showing
This menu item starts a Web browser showing one of the locally installed html manual pages.
the webpage from: https://www.wireshark.org/.
various FAQs.
45
Menu Item Accelerator Description
Downloads This menu item starts a Web browser showing
the downloads from: https://www.wireshark.org/
download.html.
Wiki This menu item starts a Web browser showing
the front page from: https://wiki.wireshark.org/.
Sample Captures This menu item starts a Web browser showing
the sample captures from:
https://wiki.wireshark.org/SampleCaptures.
About Wireshark This menu item brings up an information
window that provides various detailed information items on Wireshark, such as how it’s built, the plugins loaded, the used folders, …
Opening a Web browser might be unsupported in your version of Wireshark. If this is the case the corresponding menu items will be hidden.
NOTE
If calling a Web browser fails on your machine, nothing happens, or the browser starts but no page is shown, have a look at the web browser setting in the preferences dialog.

The “Main” Toolbar

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 even more packet data.
As in the menu, only the items useful in the current program state will be available. The others will be greyed out (e.g. you cannot save a capture file if you haven’t loaded one).
Figure 15. The “Main” toolbar
Table 14. Main toolbar items
Toolbar Icon
Toolbar Item Menu Item Description
46
[ Interfaces… ]
[ Options… ]
Capture Interfaces…
Capture Options…
This item brings up the Capture Interfaces List dialog box (discussed further in Start
Capturing).
This item brings up the Capture Options dialog box (discussed further in Start
Capturing) and allows you to start
capturing packets.
Toolbar Icon
Toolbar Item Menu Item Description
[ Start ]
[ Stop ]
[ Restart ]
[ Open… ]
[ Save As… ]
Capture Start
Capture Stop
Capture Restart
File Open…
File Save As…
This item starts capturing packets with the options from the last time.
This item stops the currently running live capture process Start Capturing).
This item stops the currently running live capture process and restarts it again, for convenience.
This item brings up the file open dialog box that allows you to load a capture file for viewing. It is discussed in more detail in
The “Open Capture File” dialog box.
This item allows you to save the current capture file to whatever file you would like. It pops up the Save Capture File As dialog box (which is discussed further in
The “Save Capture File As” dialog box).
If you currently have a temporary capture file, the Save icon will be shown instead.
[ Close ]
[ Reload ]
[ Print… ]
[ Find Packet… ]
[ Go Back ]
[ Go Forward ]
File Close
View Reload
File Print…
Edit Find Packet…
Go Go Back
Go Go Forward
This item closes the current capture. If you have not saved the capture, you will be asked to save it first.
This item allows you to reload the current capture file.
This item allows you to print all (or some of) the packets in the capture file. It pops up the Wireshark Print dialog box (which is discussed further in Printing packets).
This item brings up a dialog box that allows you to find a packet. There is further information on finding packets in
Finding packets.
This item jumps back in the packet history. Hold down the Alt key (Option on macOS) to go back in the selection history.
This item jumps forward in the packet history. Hold down the Alt key (Option on macOS) to go forward in the selection history.
[ Go to Packet… ]
Go Go to Packet…
This item brings up a dialog box that allows you to specify a packet number to go to that packet.
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Toolbar Icon
Toolbar Item Menu Item Description
[ Go To First Packet ]
[ Go To Last Packet ]
[ Colorize ]
[ Auto Scroll in Live Capture ]
[ Zoom In ]
[ Zoom Out ]
[ Normal Size ]
[ Resize Columns ]
[ Capture Filters… ]
Go First Packet
Go Last Packet
View Colorize
View Auto Scroll in Live Capture
View Zoom In
View Zoom Out
View Normal Size
View Resize Columns
Capture Capture Filters…
This item jumps to the first packet of the capture file.
This item jumps to the last packet of the capture file.
Colorize the packet list (or not).
Auto scroll packet list while doing a live capture (or not).
Zoom into the packet data (increase the font size).
Zoom out of the packet data (decrease the font size).
Set zoom level back to 100%.
Resize columns, so the content fits into them.
This item brings up a dialog box that allows you to create and edit capture filters. You can name filters, and you can save them for future use. More detail on this subject is provided in Defining and
saving filters.
[ Display Filters… ]
[ Coloring Rules… ]
[ Preferences… ]
Analyze Display Filters…
View Coloring Rules…
Edit Preferences
This item brings up a dialog box that allows you to create and edit display filters. You can name filters, and you can save them for future use. More detail on this subject is provided in Defining and
saving filters.
This item brings up a dialog box that allows you to color packets in the packet list pane according to filter expressions you choose. It can be very useful for spotting certain types of packets. More detail on this subject is provided in Packet
colorization.
This item brings up a dialog box that allows you to set preferences for many parameters that control Wireshark. You can also save your preferences so Wireshark will use them the next time you start it. More detail is provided in
Preferences
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[ Help ]
Help Contents
This item brings up help dialog box.

The “Filter” Toolbar

The filter toolbar lets you quickly edit and apply display filters. More information on display filters is available in Filtering packets while viewing.
Figure 16. The “Filter” toolbar
Table 15. Filter toolbar items
Toolbar Icon
Toolbar Item Description
[ Filter: ] Brings up the filter construction dialog, described in
The “Capture Filters” and “Display Filters” dialog boxes.
Filter input The area to enter or edit a display filter string, see
Building display filter expressions. A syntax check of
your filter string is done while you are typing. The background will turn red if you enter an incomplete or invalid string, and will become green when you enter a valid string. You can click on the pull down arrow to select a previously-entered filter string from a list. The entries in the pull down list will remain available even after a program restart.
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.
This field is also where the current filter in effect is displayed.
[Expression…] The middle button labeled “Add Expression…” opens a
dialog box that lets you edit a display filter from a list of protocol fields, described in The “Filter Expression”
dialog box
[ Clear ] Reset the current display filter and clears the edit area.
[ Apply ] 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 “Packet List” Pane

The packet list pane displays all the packets in the current capture file.
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Figure 17. The “Packet List” pane
Each line in the packet list corresponds to one packet in the capture file. If you select a line in this pane, more details will be displayed in the “Packet Details” and “Packet Bytes” panes.
While dissecting a packet, Wireshark will place information from the protocol dissectors into the columns. As higher level protocols might overwrite information from lower levels, you will typically see the information from the highest possible level only.
For example, let’s look at a packet containing TCP inside IP inside an Ethernet packet. The Ethernet dissector will write its data (such as the Ethernet addresses), the IP dissector will overwrite this by its own (such as the IP addresses), the TCP dissector will overwrite the IP information, and so on.
There are a lot of different columns available. Which columns are displayed can be selected by preference settings, see Preferences.
The default columns will show:
[ No. ] The number of the packet in the capture file. This number won’t change, even if a display
filter is used.
[ Time ] The timestamp of the packet. The presentation format of this timestamp can be
changed, see Time display formats and time references.
[ Source ] The address where this packet is coming from.
[ Destination ] The address where this packet is going to.
[ Protocol ] The protocol name in a short (perhaps abbreviated) version.
[ Length ] The length of each packet.
[ Info ] Additional information about the packet content.
The first column shows how each packet is related to the selected packet. For example, in the image above the first packet is selected, which is a DNS request. Wireshark shows a rightward arrow for the request itself, followed by a leftward arrow for the response in packet 2. Why is there a dashed line? There are more DNS packets further down that use the same port numbers. Wireshark treats them as belonging to the same conversation and draws a line connecting them.
Related packet symbols
First packet in a conversation.
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Part of the selected conversation.
Not part of the selected conversation.
Last packet in a conversation.
Request.
Response.
The selected packet acknowledges this packet.
The selected packet is a duplicate acknowledgement of this packet.
The selected packet is related to this packet in some other way, e.g. as part of reassembly.
The packet list has an Intelligent Scrollbar which shows a miniature map of nearby packets. Each
raster line of the scrollbar corresponds to a single packet, so the number of packets shown in the
map depends on your physical display and the height of the packet list. A tall packet list on a high­resolution (“Retina”) display will show you quite a few packets. In the image above the scrollbar shows the status of more than 500 packets along with the 15 shown in the packet list itself.
Right clicking will show a context menu, described in Pop-up menu of the “Packet List” pane.

The “Packet Details” Pane

The packet details pane shows the current packet (selected in the “Packet List” pane) in a more detailed form.
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Figure 18. The “Packet Details” pane
This pane shows the protocols and protocol fields of the packet selected in the “Packet List” pane. The protocols and fields of the packet shown in a tree which can be expanded and collapsed.
There is a context menu (right mouse click) available. See details in Pop-up menu of the “Packet
Details” pane.
Some protocol fields have special meanings.
Generated fields. Wireshark itself will generate additional protocol information which isn’t
present in the captured data. This information is enclosed in square brackets (“[” and “]”). Generated information includes response times, TCP analysis, IP geolocation information, and checksum validation.
Links. If Wireshark detects a relationship to another packet in the capture file it will generate a
link to that packet. Links are underlined and displayed in blue. If you double-clicked on a link Wireshark will jump to the corresponding packet.

The “Packet Bytes” Pane

The packet bytes pane shows the data of the current packet (selected in the “Packet List” pane) in a hexdump style.
Figure 19. The “Packet Bytes” pane
The “Packet Bytes” pane shows a canonical hex dump of the packet data. Each line contains the data offset, sixteen hexadecimal bytes, and sixteen ASCII bytes. Non-printalbe bytes are replaced with a period (“.”).
Depending on the packet data, sometimes more than one page is available, e.g. when Wireshark has
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reassembled some packets into a single chunk of data. (See Packet Reassembly for details). In this case you can see each data source by clicking its corresponding tab at the bottom of the pane.
Figure 20. The “Packet Bytes” pane with tabs
Additional pages typically contain data reassembled from multiple packets or decrypted data.
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.

The Statusbar

The statusbar displays informational messages.
In general, the left side will show context related information, the middle part will show information about the current capture file, and the right side will show the selected configuration profile. Drag the handles between the text areas to change the size.
Figure 21. The initial Statusbar
This statusbar is shown while no capture file is loaded, e.g. when Wireshark is started.
Figure 22. The Statusbar with a loaded capture file
The colorized bullet on the left shows the highest expert info level found in the currently
loaded capture file. Hovering the mouse over this icon will show a textual description of the expert info level, and clicking the icon will bring up the Expert Infos dialog box. For a detailed description of expert info, see Expert Information.
The left side shows information about the capture file, its name, its size and the elapsed time
while it was being captured. Hovering over a file name will show its full path and size.
The middle part shows the current number of packets in the capture file. The following values
are displayed:
Packets: The number of captured packets.
Displayed: The number of packets currently being displayed.
Marked: The number of marked packets (only displayed if packets are marked).
Dropped: The number of dropped packets (only displayed if Wireshark was unable to
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capture all packets).
Ignored: The number of ignored packets (only displayed if packets are ignored).
Load time: The time it took to load the capture (wall clock time).
The right side shows the selected configuration profile. Clicking in this part of the statusbar
will bring up a menu with all available configuration profiles, and selecting from this list will change the configuration profile.
Figure 23. The Statusbar with a configuration profile menu
For a detailed description of configuration profiles, see Configuration Profiles.
Figure 24. The Statusbar with a selected protocol field
This is displayed if you have selected a protocol field from the “Packet Details” pane.
TIP
Figure 25. The Statusbar with a display filter message
The value between the parentheses (in this example “ipv6.src”) can be used as a display filter, representing the selected protocol field.
This is displayed if you are trying to use a display filter which may have unexpected results. For a detailed description, see A Common Mistake.
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Capturing Live Network Data

Introduction

Capturing live network data is one of the major features of Wireshark.
The Wireshark capture engine provides the following features:
• Capture from different kinds of network hardware such as Ethernet or 802.11.
• Stop the capture on different triggers such as the amount of captured data, elapsed time, or the number of packets.
• Simultaneously show decoded packets while Wireshark is capturing.
• Filter packets, reducing the amount of data to be captured. See Filtering while capturing.
• Save packets in multiple files while doing a long term capture, optionally rotating through a fixed number of files (a “ringbuffer”). See Capture files and file modes.
• Simultaneously capture from multiple network interfaces.
The capture engine still lacks the following features:
• Stop capturing (or perform some other action) depending on the captured data.

Prerequisites

Setting up Wireshark to capture packets for the first time can be tricky. A comprehensive guide “How To setup a Capture” is available at https://wiki.wireshark.org/CaptureSetup.
Here are some common pitfalls:
• You may need special privileges to start a live capture.
• You need to choose the right network interface to capture packet data from.
• You need to capture at the right place in the network to see the traffic you want to see.
If you have any problems setting up your capture environment you should have a look at the guide mentioned above.

Start Capturing

The following methods can be used to start capturing packets with Wireshark:
• You can double-click on an interface in the main window.
• You can get an overview of the available interfaces using the “Capture Interfaces” dialog box
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(Capture Options…). See The “Capture Interfaces” dialog box on Microsoft Windows or The
“Capture Interfaces” dialog box on Unix/Linux for more information. You can start a capture
from this dialog box using the [ Start ] button.
You can immediately start a capture using your current settings by selecting Capture Start or by cliking the first toolbar button.
• If you already know the name of the capture interface you can start Wireshark from the command line:
$ wireshark -i eth0 -k
This will start Wireshark capturing on interface eth0. More details can be found at Start Wireshark
from the command line.

The “Capture Interfaces” dialog box

When you select Capture Options… from the main menu Wireshark pops up the “Capture Interfaces” dialog box as shown in The “Capture Interfaces” dialog box on Microsoft Windows or
The “Capture Interfaces” dialog box on Unix/Linux.
Both you and your OS can hide interfaces
This dialog box will only show the local interfaces Wireshark can access. It will also
NOTE
It is possible to select more than one interface and capture from them simultaneously.
Figure 26. The “Capture Interfaces” dialog box on Microsoft Windows
hide interfaces marked as hidden in Interface Options. As Wireshark might not be able to detect all local interfaces and it cannot detect the remote interfaces available there could be more capture interfaces available than listed.
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Figure 27. The “Capture Interfaces” dialog box on Unix/Linux
Device (Unix/Linux only)
The interface device name.
Description
The interface description provided by the operating system, or the user defined comment added in Interface Options.
IP
The first IP address Wireshark could find for this interface. You can click on the address to cycle through other addresses assigned to it, if available. If no address could be found “none” will be displayed.
Packets
The number of packets captured from this interface, since this dialog was opened. Will be greyed out, if no packet was captured in the last second.
Packets/s
Number of packets captured in the last second. Will be greyed out, if no packet was captured in the last second.
Stop
Stop a currently running capture.
Start
Start a capture on all selected interfaces immediately, using the settings from the last capture or the default settings, if no options have been set.
Options
Open the Capture Options dialog with the marked interfaces selected. See The “Capture Options”
dialog box.
Details (Microsoft Windows only)
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Open a dialog with detailed information about the interface. See The “Interface Details” dialog
box.
Help
Show this help page.
Close
Close this dialog box.

The “Capture Options” dialog box

When you select Capture Options… (or use the corresponding item in the main toolbar), Wireshark pops up the “Capture Options” dialog box as shown in The “Capture Options” dialog box.
Figure 28. The “Capture Options” dialog box
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TIP
If you are unsure which options to choose in this dialog box just try keeping the defaults as this should work well in many cases.
Capture frame
The table shows the settings for all available interfaces:
• The name of the interface and its IP addresses. If no address could be resolved from the system, “none” will be shown.
NOTE Loopback interfaces are not available on Windows platforms.
• The link-layer header type.
• The information whether promicuous mode is enabled or disabled.
• The maximum amount of data that will be captured for each packet. The default value is set to the 262144 bytes.
• The size of the kernel buffer that is reserved to keep the captured packets.
• The information whether packets will be captured in monitor mode (Unix/Linux only).
• The chosen capture filter.
By marking the checkboxes in the first column the interfaces are selected to be captured from. By double-clicking on an interface the “Edit Interface Settings” dialog box as shown in The “Edit
Interface Settings” dialog box will be opened.
Capture on all interfaces
As Wireshark can capture on multiple interfaces it is possible to choose to capture on all available interfaces.
Capture all packets in promiscuous mode
This checkbox allows you to specify that Wireshark should put all interfaces in promiscuous mode when capturing.
Capture Filter
This field allows you to specify a capture filter for all interfaces that are currently selected. Once a filter has been entered in this field, the newly selected interfaces will inherit the filter. Capture filters are discussed in more details in Filtering while capturing. It defaults to empty, or no filter.
You can also click on the [ Capture Filter ] button and Wireshark will bring up the Capture Filters dialog box and allow you to create and/or select a filter. Please see Defining and saving
filters
Compile selected BPFs
This button allows you to compile the capture filter into BPF code and pop up a window showing
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you the resulting pseudo code. This can help in understanding the working of the capture filter you created. The [ Compile Selected BPFs ] button leads you to The “Compile Results” dialog
box.
TIP Linux power user tip
The execution of BPFs can be sped up on Linux by turning on BPF JIT by executing
$ echo 1 >/proc/sys/net/core/bpf_jit_enable
if it is not enabled already. To make the change persistent you can use sysfsutils.
Manage Interfaces
The [ Manage Interfaces ] button opens the The “Add New Interfaces” dialog box where pipes can be defined, local interfaces scanned or hidden, or remote interfaces added (Windows only).
Capture File(s) frame
An explanation about capture file usage can be found in Capture files and file modes.
File
This field allows you to specify the file name that will be used for the capture file. This field is left blank by default. If the field is left blank, the capture data will be stored in a temporary file. See Capture files and file modes for details.
You can also click on the button to the right of this field to browse through the filesystem.
Use multiple files
Instead of using a single file Wireshark will automatically switch to a new one if a specific trigger condition is reached.
Use pcapng format
This checkbox allows you to specify that Wireshark saves the captured packets in pcapng format. This next generation capture file format is currently in development. If more than one interface is chosen for capturing, this checkbox is set by default. See https://wiki.wireshark.org/
Development/PcapNg for more details on pcapng.
Next file every n megabyte(s)
Multiple files only. Switch to the next file after the given number of byte(s)/kilobyte(s)/megabyte(s)/gigabyte(s) have been captured.
Next file every n minute(s)
Multiple files only: Switch to the next file after the given number of
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second(s)/minutes(s)/hours(s)/days(s) have elapsed.
Ring buffer with n files
Multiple files only: Form a ring buffer of the capture files with the given number of files.
Stop capture after n file(s)
Multiple files only: Stop capturing after switching to the next file the given number of times.
Stop Capture… frame
… after n packet(s)
Stop capturing after the given number of packets have been captured.
… after n megabytes(s)
Stop capturing after the given number of byte(s)/kilobyte(s)/megabyte(s)/gigabyte(s) have been captured. This option is greyed out if “Use multiple files” is selected.
… after n minute(s)
Stop capturing after the given number of second(s)/minutes(s)/hours(s)/days(s) have elapsed.
Display Options frame
Update list of packets in real time
This option allows you to specify that Wireshark should update the packet list pane in real time. If you do not specify this, Wireshark does not display any packets until you stop the capture. When you check this, Wireshark captures in a separate process and feeds the captures to the display process.
Automatic scrolling in live capture
This option allows you to specify that Wireshark should scroll the packet list pane as new packets come in, so you are always looking at the last packet. If you do not specify this Wireshark simply adds new packets onto the end of the list but does not scroll the packet list pane. This option is greyed out if “Update list of packets in real time” is disabled.
Name Resolution frame
Enable MAC name resolution
This option allows you to control whether or not Wireshark translates MAC addresses into names. See Name Resolution.
Enable network name resolution
This option allows you to control whether or not Wireshark translates network addresses into names. See Name Resolution.
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Enable transport name resolution
This option allows you to control whether or not Wireshark translates transport addresses into protocols. See Name Resolution.
Buttons
Once you have set the values you desire and have selected the options you need, simply click on
[ Start ] to commence the capture or [ Cancel ] to cancel the capture.

The “Edit Interface Settings” dialog box

If you double-click on an interface in The “Capture Options” dialog box the following dialog box pops up.
Figure 29. The “Edit Interface Settings” dialog box
You can set the following fields in this dialog box:
IP address
The IP address(es) of the selected interface. If no address could be resolved from the system “none” will be shown.
Link-layer header type
Unless you are in the rare situation that requires this keep the default setting. For a detailed description. See Link-layer header type
Wireless settings (Windows only)
Here you can set the settings for wireless capture using the AirPCap adapter. For a detailed description see the AirPCap Users Guide.
Remote settings (Windows only)
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Here you can set the settings for remote capture. For a detailed description see The “Remote
Capture Interfaces” dialog box
Capture packets in promiscuous mode
This checkbox allows you to specify that Wireshark should put the interface in promiscuous mode when capturing. If you do not specify this Wireshark will only capture the packets going to or from your computer (not all packets on your LAN segment).
If some other process has put the interface in promiscuous mode you may be capturing in promiscuous mode even if you turn off this option.
NOTE
Even in promiscuous mode you still won’t necessarily see all packets on your LAN segment. See the Wireshark FAQ for more information.
Limit each packet to n bytes
This field allows you to specify the maximum amount of data that will be captured for each packet, and is sometimes referred to as the snaplen. If disabled the value is set to the maximum 65535 which will be sufficient for most protocols. Some rules of thumb:
• If you are unsure just keep the default value.
• If you don’t need or don’t want all of the data in a packet - for example, if you only need the link-layer, IP, and TCP headers - you might want to choose a small snapshot length, as less CPU time is required for copying packets, less buffer space is required for packets, and thus perhaps fewer packets will be dropped if traffic is very heavy.
• If you don’t capture all of the data in a packet you might find that the packet data you want is in the part that’s dropped or that reassembly isn’t possible as the data required for reassembly is missing.
Buffer size: n megabyte(s)
Enter the buffer size to be used while capturing. This is the size of the kernel buffer which will keep the captured packets, until they are written to disk. If you encounter packet drops, try increasing this value.
Capture packets in monitor mode (Unix/Linux only)
This checkbox allows you to setup the Wireless interface to capture all traffic it can receive, not just the traffic on the BSS to which it is associated, which can happen even when you set promiscuous mode. Also it might be necessary to turn this option on in order to see IEEE 802.11 headers and/or radio information from the captured frames.
NOTE
In monitor mode the adapter might disassociate itself from the network it was associated to.
Capture Filter
This field allows you to specify a capture filter. Capture filters are discussed in more details in
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Filtering while capturing. It defaults to empty, or no filter.
You can also click on the [ Capture Filter ] button and Wireshark will bring up the “Capture Filters” dialog box and allow you to create and/or select a filter. Please see Defining and saving
filters
Compile BPF
This button allows you to compile the capture filter into BPF code and pop up a window showing you the resulting pseudo code. This can help in understanding the working of the capture filter you created.

The “Compile Results” dialog box

This figure shows the compile results of the selected interfaces.
Figure 30. The “Compile Results” dialog box
In the left window the interface names are listed. The results of an individual interface are shown in the right window when it is selected.

The “Add New Interfaces” dialog box

As a central point to manage interfaces this dialog box consists of three tabs to add or remove interfaces.
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Figure 31. The “Add New Interfaces” dialog box
Add or remove pipes
Figure 32. The “Add New Interfaces - Pipes” dialog box
To successfully add a pipe, this pipe must have already been created. Click the [ New ] button and type the name of the pipe including its path. Alternatively, the [ Browse ] button can be used to locate the pipe. With the [ Save ] button the pipe is added to the list of available interfaces. Afterwards, other pipes can be added.
To remove a pipe from the list of interfaces it first has to be selected. Then click the [ Delete ] button.
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Add or hide local interfaces
Figure 33. The “Add New Interfaces - Local Interfaces” dialog box
The tab “Local Interfaces” contains a list of available local interfaces, including the hidden ones, which are not shown in the other lists.
If a new local interface is added, for example, a wireless interface has been activated, it is not automatically added to the list to prevent the constant scanning for a change in the list of available interfaces. To renew the list a rescan can be done.
One way to hide an interface is to change the preferences. If the “Hide” checkbox is activated and the [ Apply ] button clicked, the interface will not be seen in the lists of the “Capture Interfaces” dialog box any more. The changes are also saved in the preferences file.
Add or hide remote interfaces
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Figure 34. The “Add New Interfaces - Remote Interfaces” dialog box
In this tab interfaces on remote hosts can be added. One or more of these interfaces can be hidden. In contrast to the local interfaces they are not saved in the preferences file.
To remove a host including all its interfaces from the list, it has to be selected. Then click the [Delete] button.
For a detailed description see The “Remote Capture Interfaces” dialog box

The “Remote Capture Interfaces” dialog box

Besides doing capture on local interfaces Wireshark is capable of reaching out across the network to a so called capture daemon or service processes to receive captured data from.
Microsoft Windows only
NOTE
The Remote Packet Capture Protocol service must first be running on the target platform before Wireshark can connect to it. The easiest way is to install WinPcap from https://www.winpcap.org/
install/ on the target. Once installation is completed go to the Services control panel, find the
Remote Packet Capture Protocol service and start it.
NOTE
To access the Remote Capture Interfaces dialog use the “Add New Interfaces - Remote” dialog. See
The “Add New Interfaces - Remote Interfaces” dialog box and select [ Add ].
This dialog and capability is only available on Microsoft Windows. On Linux/Unix you can achieve the same effect (securely) through an SSH tunnel.
Make sure you have outside access to port 2002 on the target platform. This is the port where the Remote Packet Capture Protocol service can be reached by default.
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Remote Capture Interfaces
Figure 35. The “Remote Capture Interfaces” dialog box
You have to set the following parameters in this dialog:
Host
Enter 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. The list can be emptied by choosing “Clear list” from the drop down list.
Port
Set the port number where the Remote Packet Capture Protocol service is listening on. Leave open to use the default port (2002).
Null authentication
Select this if you don’t need authentication to take place for a remote capture to be started. This depends on the target platform. Configuring the target platform like this makes it insecure.
Password authentication
This is the normal way of connecting to a target platform. Set the credentials needed to connect to the Remote Packet Capture Protocol service.
Remote Capture Settings
The remote capture can be further fine tuned to match your situation. The [ Remote Settings ] button in The “Edit Interface Settings” dialog box gives you this option. It pops up the dialog shown in The “Remote Capture Settings” dialog box.
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Figure 36. The “Remote Capture Settings” dialog box
You can set the following parameters in this dialog:
Do not capture own RPCAP traffic
This option sets a capture filter so that the traffic flowing back from the Remote Packet Capture Protocol service to Wireshark isn’t captured as well and also send back. The recursion in this saturates the link with duplicate traffic.
You only should switch this off when capturing on an interface other than the interface connecting back to Wireshark.
Use UDP for data transfer
Remote capture control and data flows over a TCP connection. This option allows you to choose an UDP stream for data transfer.
Sampling option None
This option instructs the Remote Packet Capture Protocol service to send back all captured packets which have passed the capture filter. This is usually not a problem on a remote capture session with sufficient bandwidth.
Sampling option 1 of x packets
This option limits the Remote Packet Capture Protocol service to send only a sub sampling of the captured data, in terms of number of packets. This allows capture over a narrow band remote capture session of a higher bandwidth interface.
Sampling option 1 every x milliseconds
This option limits the Remote Packet Capture Protocol service to send only a sub sampling of the captured data in terms of time. This allows capture over a narrow band capture session of a higher bandwidth interface.

The “Interface Details” dialog box

When you select Details from the Capture Interface menu, Wireshark pops up the “Interface Details” dialog box as shown in The “Interface Details” dialog box. This dialog shows various characteristics and statistics for the selected interface.
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NOTE
Microsoft Windows only
This dialog is only available on Microsoft Windows
Figure 37. The “Interface Details” dialog box

Capture files and file modes

While capturing the underlying libpcap 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. These options are controlled in the “Output” tab in the “Capture Options” dialog.
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Figure 38. Capture output options
Working with large files (several hundred MB) can be quite slow. If you plan to do a
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long term capture or capturing from a high traffic network, think about using one of the “Multiple files” options. This will spread the captured packets over several smaller files which can be much more pleasant to work with.
Using Multiple files 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). As it keeps this information only for the loaded file, using one of the multiple file modes may cut these contexts. If the establishing phase is saved in one file and the things you would like to see is in another, you might not see some of the valuable context related information.
Information about the folders used for capture files can be found in Files and Folders.
Table 16. Capture file mode selected by capture options
File Name “Create a
new file…”
“Use a ring buffer…”
Mode Resulting filename(s) used
- - - Single temporary file wiresharkXXXXXX (where XXXXXX is a unique number)
foo.cap - - Single named file foo.cap
foo.cap x - Multiple files,
continuous
foo.cap x x Multiple files, ring
buffer
foo_00001_20100205110102.cap, foo_00002_20100205110318.cap, …
foo_00001_20100205110102.cap, foo_00002_20100205110318.cap, …
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Single temporary file
A temporary file will be created and used (this is the default). After capturing is stopped this file can be saved later under a user specified name.
Single named file
A single capture file will be used. If you want to place the new capture file in a specific folder choose this mode.
Multiple files, continuous
Like the “Single named file” mode, but a new file is created and used after reaching one of the multiple file switch conditions (one of the “Next file every …” values).
Multiple files, ring buffer
Much like “Multiple files continuous”, reaching one of the multiple files switch conditions (one of the “Next file every …” values) will switch to the next file. This will be a newly created file if value of “Ring buffer with n files” is not reached, otherwise it will replace the oldest of the formerly used files (thus forming a “ring”). + This mode will limit the maximum disk usage, even for an unlimited amount of capture input data, only keeping the latest captured data.

Link-layer header type

In most cases you won’t have to modify link-layer header type. Some exceaptions are as follows:
If you are capturing on an Ethernet device you might be offered a choice of “Ethernet” or “DOCSIS”. If you are capturing traffic from a Cisco Cable Modem Termination System that is putting DOCSIS traffic onto the Ethernet to be captured, select “DOCSIS”, 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”. “Ethernet” will cause the captured packets to have fake (“cooked”) Ethernet headers. “802.11” will cause them to have full IEEE 802.11 headers. 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 Endace DAG card connected to a synchronous serial line you might be offered a choice of “PPP over serial” or “Cisco HDLC”. If the protocol on the serial line is PPP, select “PPP over serial” and if the protocol on the serial line is Cisco HDLC, select “Cisco HDLC”.
If you are capturing on an Endace DAG card connected to an ATM network you might be offered a choice of “RFC 1483 IP-over-ATM” or “Sun raw ATM”. If the only traffic being captured is RFC 1483 LLC-encapsulated IP, or if the capture needs to be read by an application that doesn’t support SunATM headers, select “RFC 1483 IP-over-ATM”, otherwise select “Sun raw ATM”.

Filtering while capturing

Wireshark uses the libpcap filter language for capture filters. A brief overview of the syntax follows. Complete documentation can be found in the pcap-filter man page. You can find a lot of
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Capture Filter examples at https://wiki.wireshark.org/CaptureFilters.
You enter the capture filter into the “Filter” field of the Wireshark “Capture Options” dialog box, as shown in The “Capture Options” dialog box.
A capture filter takes the form of a series of primitive expressions connected by conjunctions (and/or) and optionally preceded by not:
[not] primitive [and|or [not] primitive ...]
An example is shown in A capture filter for telnet that captures traffic to and from a particular host.
Example 1. A capture filter for telnet that captures traffic to and from a particular host
A capture filter for telnet that captures traffic to and from a particular host
tcp port 23 and host 10.0.0.5
This example captures telnet traffic to and from the host 10.0.0.5, and shows how to use two primitives and the and conjunction. Another example is shown in Capturing all telnet traffic not
from 10.0.0.5, and shows how to capture all telnet traffic except that from 10.0.0.5.
Example 2. Capturing all telnet traffic not from 10.0.0.5
Capturing all telnet traffic not from 10.0.0.5
tcp port 23 and not src host 10.0.0.5
A primitive is simply one of the following: [src|dst] host <host>
This primitive allows you to filter on a host IP address or name. You can optionally precede the primitive with the keyword src|dst to specify that you are only interested in source or destination addresses. If these are not present, packets where the specified address appears as either the source or the destination address will be selected.
ether [src|dst] host <ehost>
This primitive allows you to filter on Ethernet host addresses. You can optionally include the keyword src|dst between the keywords ether and host to specify that you are only interested in source or destination addresses. If these are not present, packets where the specified address appears in either the source or destination address will be selected.
gateway host <host>
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This primitive allows you to filter on packets that used host as a gateway. That is, where the Ethernet source or destination was host but neither the source nor destination IP address was
host.
[src|dst] net <net> [{mask <mask>}|{len <len>}]
This primitive allows you to filter on network numbers. 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 netmask or the CIDR prefix for the network if they are different from your own.
[tcp|udp] [src|dst] port <port>
This primitive allows you to filter on TCP and UDP port numbers. 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. The keywords tcp|udp must appear before src|dst.
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.
less|greater <length>
This primitive allows you to filter on packets whose length was less than or equal to the specified length, or greater than or equal to the specified length, respectively.
ip|ether proto <protocol>
This primitive allows you to filter on the specified protocol at either the Ethernet layer or the IP layer.
ether|ip broadcast|multicast
This primitive allows you to filter on either Ethernet or IP broadcasts or multicasts.
<expr> relop <expr>
This primitive allows you to create complex filter expressions that select bytes or ranges of bytes in packets. Please see the pcap-filter man page at http://www.tcpdump.org/manpages/pcap-
filter.7.html for more details.
Automatic Remote Traffic Filtering
If Wireshark is running remotely (using e.g. SSH, an exported X11 window, a terminal server, …), the remote content has to be transported over the network, adding a lot of (usually unimportant) packets to the actually interesting traffic.
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.
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The following environment variables are analyzed:
SSH_CONNECTION (ssh)
<remote IP> <remote port> <local IP> <local port>
SSH_CLIENT (ssh)
<remote IP> <remote port> <local port>
REMOTEHOST (tcsh, others?)
<remote name>
DISPLAY (x11)
[remote name]:<display num>
SESSIONNAME (terminal server)
<remote name>
On Windows it asks the operating system if it’s running in a Remote Desktop Services environment.
While a Capture is running …
You might see the following dialog box while a capture is running:
Figure 39. The “Capture Information” dialog box
This dialog box shows a list of protocols and their activity over time. It can be enabled via the “capture.show_info” setting in the “Advanced” preferences.
Stop the running capture
A running capture session will be stopped in one of the following ways:
1. The [ Stop Capture ] button in the “Capture Information” dialog box.
2.
The Capture Stop menu item.
3. The [ Stop ] toolbar button.
4. Pressing Ctrl+E.
5. The capture will be automatically stopped if one of the Stop Conditions is met, e.g. the maximum
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amount of data was captured.
Restart a running capture
A running capture session can be restarted with the same capture options as the last time, this will remove all packets previously captured. This can be useful, if some uninteresting packets are captured and there’s no need to keep them.
Restart is a convenience function and equivalent to a capture stop following by an immediate capture start. A restart can be triggered in one of the following ways:
1.
Using the Capture Restart menu item.
2. Using the [ Restart ] toolbar button.
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File Input, Output, and Printing

Introduction

This chapter will describe input and output of capture data.
• Open capture files in various capture file formats
• Save/Export capture files in various capture file formats
• Merge capture files together
• Import text files containing hex dumps of packets
• Print packets

Open capture files

Wireshark can read in previously saved capture files. To read them, simply select the File Open menu or toolbar item. Wireshark will then pop up the “File Open” dialog box, which is discussed in more detail in The “Open Capture File” dialog box.
It’s convenient to use drag-and-drop
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If you haven’t previously saved the current capture file you will be asked to do so to prevent data loss. This warning can be disabled in the preferences.
In addition to its native file format (pcapng), Wireshark can read and write capture files from a large number of other packet capture programs as well. See Input File Formats for the list of capture formats Wireshark understands.
You can open a file by simply dragging it in your file manager and dropping it onto Wireshark’s main window. However, drag-and-drop may not be available in all desktop environments.
The “Open Capture File” dialog box
The “Open Capture File” dialog box allows you to search for a capture file containing previously captured packets for display in Wireshark. The following sections show some examples of the Wireshark “Open File” dialog box. The appearance of this dialog depends on the system. However, the functionality should be the same across systems.
Common dialog behaviour on all systems:
• Select files and directories.
• Click the [ Open ] or [ OK ] button to accept your selected file and open it.
• Click the [ Cancel ] button to go back to Wireshark and not load a capture file.
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Wireshark extensions to the standard behaviour of these dialogs:
• View file preview information such as the filesize and the number of packets in a selected a capture file.
• Specify a display filter with the [ Filter ] button and filter field. This filter will be used when opening the new file. The text field background becomes green for a valid filter string and red for an invalid one. Clicking on the [ Filter ] button causes Wireshark to pop up the “Filters” dialog box (which is discussed further in Filtering packets while viewing).
• Specify which type of name resolution is to be performed for all packets by clicking on one of the “… name resolution” check buttons. Details about name resolution can be found in Name
Resolution.
Save a lot of time loading huge capture files
You can change the display filter and name resolution settings later while viewing the
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packets. However, loading huge capture files can take a significant amount of extra time if these settings are changed later, so in such situations it can be a good idea to set at least the filter in advance here.
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Figure 40. “Open” on Microsoft Windows
This is the common Windows file open dialog - plus some Wireshark extensions.
Specific for this dialog:
• The [ Help ] button will lead you to this section of this “User’s Guide”.
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Figure 41. “Open” - Linux and UNIX
This is the common Gimp/GNOME file open dialog plus some Wireshark extensions.
Specific for this dialog:
• The [ + ] button allows you to add a directory selected in the right-hand pane to the favorites list on the left. These changes are persistent.
• The [ - ] button allows you to remove a selected directory from the list. Some items (such as “Desktop”) cannot be removed from the favorites list.
• If Wireshark doesn’t recognize the selected file as a capture file it will grey out the [ Open ] button.
Input File Formats
The following file formats from other capture tools can be opened by Wireshark:
• pcapng. A flexible, etensible successor to the libpcap format. Wireshark 1.8 and later save files as pcapng by default. Versions prior to 1.8 used libpcap.
• libpcap. The default format used by the libpcap packet capture library. Used by tcpdump, _Snort, Nmap, Ntop, and many other tools.
• Oracle (previously Sun) snoop and atmsnoop
• Finisar (previously Shomiti) Surveyor captures
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• Microsoft Network Monitor captures
• Novell LANalyzer captures
• AIX iptrace captures
• Cinco Networks NetXray captures
• Network Associates Windows-based Sniffer and Sniffer Pro captures
• Network General/Network Associates DOS-based Sniffer (compressed or uncompressed) captures
• AG Group/WildPackets/Savvius EtherPeek/TokenPeek/AiroPeek/EtherHelp/PacketGrabber captures
• RADCOM’s WAN/LAN Analyzer captures
• Network Instruments Observer version 9 captures
• Lucent/Ascend router debug output
• HP-UX’s nettl
• Toshiba’s ISDN routers dump output
• ISDN4BSD i4btrace utility
• traces from the EyeSDN USB S0
• IPLog format from the Cisco Secure Intrusion Detection System
• pppd logs (pppdump format)
• the output from VMS’s TCPIPtrace/TCPtrace/UCX$TRACE utilities
• the text output from the DBS Etherwatch VMS utility
• Visual Networks’ Visual UpTime traffic capture
• the output from CoSine L2 debug
• the output from Accellent’s 5Views LAN agents
• Endace Measurement Systems’ ERF format captures
• Linux Bluez Bluetooth stack hcidump -w traces
• Catapult DCT2000 .out files
• Gammu generated text output from Nokia DCT3 phones in Netmonitor mode
• IBM Series (OS/400) Comm traces (ASCII & UNICODE)
• Juniper Netscreen snoop captures
• Symbian OS btsnoop captures
• Tamosoft CommView captures
• Textronix K12xx 32bit .rf5 format captures
• Textronix K12 text file format captures
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• Apple PacketLogger captures
• Captures from Aethra Telecommunications’ PC108 software for their test instruments
New file formats are added from time to time.
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.

Saving captured packets

You can save captured packets simply by using the File Save As… menu item. You can choose which packets to save and which file format to be used.
Not all information will be saved in a capture file. For example, most file formats don’t record the number of dropped packets. See Capture Files for details.
The “Save Capture File As” dialog box
The “Save Capture File As” dialog box allows you to save the current capture to a file. The following sections show some examples of this dialog box. The appearance of this dialog depends on the system. However, the functionality should be the same across systems.
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Figure 42. “Save” on Microsoft Windows
This is the common Windows file save dialog with some additional Wireshark extensions.
Specific behavior for this dialog:
• If available, the “Help” button will lead you to this section of this “User’s Guide”.
• If you don’t provide a file extension to the filename (e.g. .pcap) Wireshark will append the standard file extension for that file format.
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Figure 43. “Save” on Linux and UNIX
This is the common Gimp/GNOME file save dialog with additional Wireshark extensions.
Specific for this dialog:
• Clicking on the + at “Browse for other folders” will allow you to browse files and folders in your file system.
With this dialog box, you can perform the following actions:
1. Type in the name of the file you wish to save the captured packets in, as a standard file name in your file system.
2. Select the directory to save the file into.
3. Select the range of the packets to be saved. See The “Packet Range” frame.
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4. Specify the format of the saved capture file by clicking on the File type drop down box. You can choose from the types described in Output File Formats.
Some capture formats may not be available depending on the packet types captured.
Wireshark can convert file formats
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You can convert capture files from one format to another by reading in a capture file and writing it out using a different format.
1. Click the [ Save ] or [ OK ] button to accept your selected file and save to it. If Wireshark has a problem saving the captured packets to the file you specified it will display an error dialog box. After clicking [ OK ] on that error dialog box you can try again.
2. Click on the [ Cancel ] button to go back to Wireshark without saving any packets.
Output File Formats
Wireshark can save the packet data in its native file format (pcapng) and in the file formats of other protocol analyzers so other tools can read the capture data.
Different file formats have different time stamp accuracies
WARNING
The following file formats can be saved by Wireshark (with the known file extensions):
Saving from the currently used file format to a different format may reduce the time stamp accuracy; see the Time Stamps for details.
• pcapng (*.pcapng). A flexible, etensible successor to the libpcap format. Wireshark 1.8 and later save files as pcapng by default. Versions prior to 1.8 used libpcap.
• libpcap, tcpdump and various other tools using tcpdump’s capture format (*.pcap,*.cap,*.dmp)
• Accellent 5Views (*.5vw)
• HP-UX’s nettl (*.TRC0,*.TRC1)
• Microsoft Network Monitor - NetMon (*.cap)
• Network Associates Sniffer - DOS (*.cap,*.enc,*.trc,*fdc,*.syc)
• Network Associates Sniffer - Windows (*.cap)
• Network Instruments Observer version 9 (*.bfr)
• Novell LANalyzer (*.tr1)
• Oracle (previously Sun) snoop (*.snoop,*.cap)
• Visual Networks Visual UpTime traffic (*.*)
New file formats are added from time to time.
Whether or not the above tools will be more helpful than Wireshark is a different question ;-)
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Third party protocol analyzers may require specific file extensions
NOTE
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.

Merging capture files

Sometimes you need to merge several capture files into one. For example, this can be useful if you have captured simultaneously from multiple interfaces at once (e.g. using multiple instances of Wireshark).
There are three ways to merge capture files using Wireshark:
Use the File Merge menu to open the “Merge” dialog. See The “Merge with Capture File” dialog
box. This menu item will be disabled unless you have loaded a capture file.
• Use drag-and-drop to drop multiple files on the main window. Wireshark will try to merge the packets in chronological order from the dropped files into a newly created temporary file. If you drop only a single file it will simply replace the existing capture.
• Use the mergecap tool, a command line tool to merge capture files. This tool provides the most options to merge capture files. See mergecap: Merging multiple capture files into one for details.
The “Merge with Capture File” dialog box
This dialog box let you select a file to be merged into the currently loaded file. If your current data has not been saved you will be asked to save it first.
Most controls of this dialog will work the same way as described in the “Open Capture File” dialog box, see The “Open Capture File” dialog box.
Specific controls of this merge dialog are:
Prepend packets to existing file
Prepend the packets from the selected file before the currently loaded packets.
Merge packets chronologically
Merge both the packets from the selected and currently loaded file in chronological order.
Append packets to existing file
Append the packets from the selected file after the currently loaded packets.
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Figure 44. “Merge” on Microsoft Windows
This is the common Windows file open dialog with additional Wireshark extensions.
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Figure 45. “Merge” on Linux and UNIX
This is the common Gimp/GNOME file open dialog with additional Wireshark extensions.

Import hex dump

Wireshark can read in an ASCII hex dump and write the data described into a temporary libpcap capture file. It can read hex dumps with multiple packets in them, and build a capture file of multiple packets. It is also capable of generating dummy Ethernet, IP and UDP, TCP, or SCTP headers, in order to build fully processable packet dumps from hexdumps of application-level data only.
Wireshark understands a hexdump of the form generated by od -Ax -tx1 -v. In other words, each byte is individually displayed and surrounded with a space. Each line begins with an offset describing the position in the file. The offset is a hex number (can also be octal or decimal), of more than two hex digits. Here is a sample dump that can be imported:
000000 00 e0 1e a7 05 6f 00 10 ........
000008 5a a0 b9 12 08 00 46 00 ........
000010 03 68 00 00 00 00 0a 2e ........
000018 ee 33 0f 19 08 7f 0f 19 ........
000020 03 80 94 04 00 00 10 01 ........
000028 16 a2 0a 00 03 50 00 0c ........
000030 01 01 0f 19 03 80 11 01 ........
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There is no limit on the width or number of bytes per line. Also the text dump at the end of the line is ignored. Byte and hex numbers can be uppercase or lowercase. Any text before the offset is ignored, including email forwarding characters >. Any lines of text between the bytestring lines are ignored. The offsets are used to track the bytes, so offsets must be correct. Any line which has only bytes without a leading offset is ignored. An offset is recognized as being a hex number longer than two characters. Any text after the bytes is ignored (e.g. the character dump). Any hex numbers in this text are also ignored. An offset of zero is indicative of starting a new packet, so a single text file with a series of hexdumps can be converted into a packet capture with multiple packets. Packets may be preceded by a timestamp. These are interpreted according to the format given. If not the first packet is timestamped with the current time the import takes place. Multiple packets are read in with timestamps differing by one microsecond each. In general, short of these restrictions, Wireshark is pretty liberal about reading in hexdumps and has been tested with a variety of mangled outputs (including being forwarded through email multiple times, with limited line wrap etc.)
There are a couple of other special features to note. Any line where the first non-whitespace character is # will be ignored as a comment. Any line beginning with #TEXT2PCAP is a directive and options can be inserted after this command to be processed by Wireshark. 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. Wireshark also allows the user to read in dumps of application-level data, by inserting dummy L2, L3 and L4 headers before each packet. The user can elect to insert Ethernet headers, Ethernet and IP, or Ethernet, IP and UDP/TCP/SCTP headers before each packet. This allows Wireshark or any other full-packet decoder to handle these dumps.
The “Import from Hex Dump” dialog box
This dialog box lets you select a text file, containing a hex dump of packet data, to be imported and set import parameters.
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Figure 46. The “Import from Hex Dump” dialog
Specific controls of this import dialog are split in two sections:
Input
Determine which input file has to be imported and how it is to be interpreted.
Import
Determine how the data is to be imported.
The input parameters are as follows:
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Filename / Browse
Enter the name of the text file to import. You can use Browse to browse for a file.
Offsets
Select the radix of the offsets given in the text file to import. This is usually hexadecimal, but decimal and octal are also supported.
Date/Time
Tick this checkbox if there are timestamps associated with the frames in the text file to import you would like to use. Otherwise the current time is used for timestamping the frames.
Format
This is the format specifier used to parse the timestamps in the text file to import. It uses a simple syntax to describe the format of the timestamps, using %H for hours, %M for minutes, %S for seconds, etc. The straightforward HH:MM:SS format is covered by %T. For a full definition of the syntax look for strptime(3).
The import parameters are as follows:
Encapsulation type
Here you can select which type of frames you are importing. This all depends on from what type of medium the dump to import was taken. It lists all types that Wireshark understands, so as to pass the capture file contents to the right dissector.
Dummy header
When Ethernet encapsulation is selected you have to option to prepend dummy headers to the frames to import. These headers can provide artificial Ethernet, IP, UDP or TCP or SCTP headers and SCTP data chunks. When selecting a type of dummy header the applicable entries are enabled, others are grayed out and default values are used.
Maximum frame length
You may not be interested in the full frames from the text file, just the first part. Here you can define how much data from the start of the frame you want to import. If you leave this open the maximum is set to 65535 bytes.
Once all input and import parameters are setup click [ OK ] to start the import. If your current data wasn’t saved before you will be asked to save it first.
When completed there will be a new capture file loaded with the frames imported from the text file.

File Sets

When using the “Multiple Files” option while doing a capture (see: Capture files and file modes), the capture data is spread over several capture files, called a file set.
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As it can become tedious to work with a file set by hand, Wireshark provides some features to handle these file sets in a convenient way.
How does Wireshark detect the files of a file set?
A filename in a file set uses the format Prefix_Number_DateTimeSuffix which might look something like test_00001_20060420183910.pcap. All files of a file set share the same prefix (e.g. “test”) and suffix (e.g. “.pcap”) and a varying middle part.
To find the files of a file set, Wireshark scans the directory where the currently loaded file resides and checks for files matching the filename pattern (prefix and suffix) of the currently loaded file.
This simple mechanism usually works well but has its drawbacks. If several file sets were captured with the same prefix and suffix, Wireshark will detect them as a single file set. If files were renamed or spread over several directories the mechanism will fail to find all files of a set.
The following features in the File File Set submenu are available to work with file sets in a convenient way:
• The “List Files” dialog box will list the files Wireshark has recognized as being part of the current file set.
[ Next File ] closes the current and opens the next file in the file set.
[ Previous File ] closes the current and opens the previous file in the file set.
The “List Files” dialog box
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Figure 47. The “List Files” dialog box
Each line contains information about a file of the file set:
Filename the name of the file. If you click on the filename (or the radio button left to it), the current file will be closed and the corresponding capture file will be opened.
Created the creation time of the file
Last Modified the last time the file was modified
Size the size of the file
The last line will contain info about the currently used directory where all of the files in the file set can be found.
The content of this dialog box is updated each time a capture file is opened/closed.
The [ Close ] button will, well, close the dialog box.
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Exporting data

Wireshark provides several ways and formats to export packet data. This section describes general ways to export data from the main Wireshark application. There are more specialized functions to export specific data which are described elsewhere.
The “Export as Plain Text File” dialog box
Export packet data into a plain ASCII text file, much like the format used to print packets.
If you would like to be able to import any previously exported packets from a plain text file it is recommended that you:
• Add the “Absolute date and time” column.
• Temporarily hide all other columns.
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Disable the Edit Preferences Protocols Data “Show not dissected data on new Packet Bytes pane” preference. More details are provided in Preferences
• Include the packet summary line.
• Exclude column headings.
• Exclude packet details.
• Include the packet bytes.
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Figure 48. The “Export as Plain Text File” dialog box
• The “Export to file:” frame chooses the file to export the packet data to.
• The “Packet Range” frame is described in The “Packet Range” frame.
• The “Packet Details” frame is described in The Packet Format frame.
The “Export as PostScript File” dialog box
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Figure 49. The “Export as PostScript File” dialog box
Export to file: frame chooses the file to export the packet data to.
• The Packet Range frame is described in The “Packet Range” frame.
• The Packet Details frame is described in The Packet Format frame.
The “Export as CSV (Comma Separated Values) File” dialog box
Export packet summary into CSV, used e.g. by spreadsheet programs to im-/export data.
Export to file: frame chooses the file to export the packet data to.
• The Packet Range frame is described in The “Packet Range” frame.
The “Export as C Arrays (packet bytes) file” dialog box
Export packet bytes into C arrays so you can import the stream data into your own C program.
Export to file: frame chooses the file to export the packet data to.
• The Packet Range frame is described in The “Packet Range” frame.
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The “Export as PSML File” dialog box
Export packet data into PSML. This is an XML based format including only the packet summary. The PSML file specification is available at: http://www.nbee.org/doku.php?id=netpdl:psml_specification.
Figure 50. The “Export as PSML File” dialog box
Export to file: frame chooses the file to export the packet data to.
• The Packet Range frame is described in The “Packet Range” frame.
There’s no such thing as a packet details frame for PSML export, as the packet format is defined by the PSML specification.
The “Export as PDML File” dialog box
Export packet data into PDML. This is an XML based format including the packet details. The PDML file specification is available at: http://www.nbee.org/doku.php?id=netpdl:pdml_specification.
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NOTE
The PDML specification is not officially released and Wireshark’s implementation of it is still in an early beta state, so please expect changes in future Wireshark versions.
Figure 51. The “Export as PDML File” dialog box
Export to file: frame chooses the file to export the packet data to.
• The Packet Range frame is described in The “Packet Range” frame.
There’s no such thing as a packet details frame for PDML export, as the packet format is defined by the PDML specification.
The “Export selected packet bytes” dialog box
Export the bytes selected in the “Packet Bytes” pane into a raw binary file.
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Figure 52. The “Export Selected Packet Bytes” dialog box
Name: the filename to export the packet data to.
• The Save in folder: field lets you select the folder to save to (from some predefined folders).
Browse for other folders provides a flexible way to choose a folder.
The “Export Objects” dialog box
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. For example, if you select HTTP, you can export HTML documents, images, executables, and any other files transferred over HTTP 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.
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