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

Following a DHCP example

When a host boots up and attempts to join the network, one of the first things they must do is obtain an IP address.

In this section, we'll look at what you may see when a client issues a DHCP Release. Then, we'll step through the DORA process and outline the details of each of the steps that are taken when a client obtains an IP address.

Let's start by seeing what happens when a client releases their network address.

Releasing an IP address

There are times when you may need to release and renew an IP address, such as during a troubleshooting exercise.

One way to release an IP address on a Windows machine is by opening a Command Prompt and typing ipconfig /release. To renew the IP address, type ipconfig /renew.

I did a manual release and then renewed while capturing traffic with Wireshark. The results are shown here:

Figure 14.11 – DHCP Release and Renew

In Frame 1, you can see where I have...