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

Filtering network traffic

Wireshark, along with many other packet analysis tools, can take a large capture, filter specific types of traffic, and refine your view to help with analysis. Within Wireshark there are several options you can use to filter traffic:

  • Display filters: Used during an active capture or on a pre-captured file
  • Capture filters: Applied prior to capture to only display a certain type of traffic
  • Expressions: Creates complex filters using logical operators
  • Shortcuts: Builds a filter on the fly while analyzing packets

Wireshark has capture and display filters that can be used to refine your view. Each filter is applied during a specific time when analyzing traffic. In the next section, let's explore when the best time is to apply a filter.

Analyzing traffic

While examining traffic, there are four main phases of packet analysis, as discussed in Chapter 2, Using Wireshark. The phases are Gather, Decode, Analyze, and Display, as shown...