Book Image

Learn Wireshark, - Second Edition

By : Lisa Bock
5 (1)
Book Image

Learn Wireshark, - Second Edition

5 (1)
By: Lisa Bock

Overview of this book

Wireshark is a popular and powerful packet analysis tool that helps network administrators investigate latency issues and potential attacks. Over the years, there have been many enhancements to Wireshark’s functionality. This book will guide you through essential features so you can capture, display, and filter data with ease. In addition to this, you’ll gain valuable tips on lesser-known configuration options, which will allow you to complete your analysis in an environment customized to suit your needs. This updated second edition of Learn Wireshark starts by outlining the benefits of traffic analysis. You’ll discover the process of installing Wireshark and become more familiar with the interface. Next, you’ll focus on the Internet Suite and then explore deep packet analysis of common protocols such as DNS, DHCP, HTTP, and ARP. The book also guides you through working with the expert system to detect network latency issues, create I/O and stream graphs, subset traffic, and save and export captures. Finally, you’ll understand how to share captures using CloudShark, a browser-based solution for analyzing packet captures. By the end of this Wireshark book, you’ll have the skills and hands-on experience you need to conduct deep packet analysis of common protocols and network troubleshooting as well as identify security issues.
Table of Contents (28 chapters)
1
Part 1 Traffic Capture Overview
6
Part 2 Getting Started with Wireshark
11
Part 3 The Internet Suite TCP/IP
16
Part 4 Deep Packet Analysis of Common Protocols
21
Part 5 Working with Packet Captures

Outlining the various filters and graphs

Within CS, there are several ways to view your captures. Filters narrow a capture to display only the traffic you want to see, and graphs provide a visual representation of the data.

One common task is to apply a display filter. CS's easy-to-use interface provides a way to narrow your scope. Let's learn more about this in the next section.

Displaying data using filters

Display filters in CS are comparable to the way Wireshark filters data. Filters can be applied to identify packets with specific ports, IP addresses, or protocols by entering a filter in the upper left-hand side of the interface. After you enter a filter, select Apply to run the filter.

In the following screenshot, I used the http filter, which narrowed the capture to show only HTTP traffic:

Figure 20.16 – HTTP traffic

When using display filters, the syntax must be correct, or you will see an error. For example, the TCP filter...