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

Chapter 14: Examining DHCP

Whenever you first boot up your machine to start your day, your operating system (OS) moves through a series of events. One of those events is obtaining an internet protocol (IP) address. The protocol that's used to obtain your IP address is known as Dynamic Host Configuration Protocol (DHCP). In this chapter, we'll begin by reviewing the purpose of DHCP. Then, we step through the DHCP process, which has four steps: discover, offer, request, and acknowledgment, also called the DORA process.

To familiarize ourselves with the elements that make the DHCP process possible, we'll take a closer look at the field values in a DHCP header. In addition, you'll get a better understanding of the role of the client and server during this process. We'll also take a look at DHCPv6, which is used to provide an IP address to the growing number of networks that are moving toward employing IPv6. We'll also review some of the security aspects...