Reading a packet capture file with Wireshark and tshark
Needle in Haystack
Wireshark doesn’t just work in real time. If you save a history of network activity in a pcap file using a tool such as tcpdump, you can filter the data with Wireshark to search for evidence.
Intrusion detection tools that use the libpcap C/ C++ library for network traffic capture (such as Snort and Tcpdump) can output packet capture information to a file for later reference. The format of this capture file is known as pcap. By capturing packet data to a file, an investigator can return later to study the history of an intrusion attempt – or to turn up other important clues about clandestine activity on the network.
Of course, the traffic history data stored in a pcap file is much too vast to study by just viewing the file manually. Security experts use specialized filtering tools to search through the file for pertinent information. One way to look for clues in a pcap file is to use the Wireshark protocol analysis tool [3] and its accompanying command-line utility tshark.
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Direct Download
Read full article as PDF:
Price $2.95
News
-
Armbian 21.05 Now Available
The Armbian developers have released the latest update to the Debian-based Linux distribution geared for ARM and embedded devices.
-
StarLabs has Released Another Linux Laptop
A new 14" Linux laptop has been released by the company that created the 11" Star Lite and can be purchased with your choice of Linux distribution.
-
Ubuntu 21.04 Adds Support for Active Directory and Other Major Changes
In a bid to help make Linux more viable for the business desktop, Canonical adds support for Active Directory and a few other notable changes.
-
GNOME 40 Available on openSUSE
The rolling release edition of openSUSE, Tumbleweed, now offers the latest version of the GNOME desktop.
-
Apple M1 Hardware Support to be Merged into Linux Kernel 5.13
Linux users will be able to install their favorite distribution on Apple’s M1-based hardware.
-
KDE Launches the Qt 5 Patch Collection
To support and maintain a stable Qt 5 for KDE Gears and Frameworks, KDE will maintain a patch collection.
-
Linux Creator Warns Next Kernel Could be Delayed
Linus Torvalds has issued concern about the size of kernel 5.12 and possible delays for its release.
-
System76 Updates its Pangolin Laptop
System76 has released a much-anticipated AMD version of their most popular laptop, the Pangolin.
-
New Debian-Based Distribution Arrives on the Market
TelOS is a new Debian-based Linux distribution with a customized, touch-screen-ready KDE Plasma 5 desktop.
-
System76 Releases New Thelio Desktop
One of the most ardent supporters of open source hardware has released a new desktop machine for home or office.