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

Summary

In this chapter, we focused on the transport layer (or Layer 4) of the OSI model, specifically the two predominant protocols in this layer, TCP and UDP. We started with an overview of the transport layer. We then evaluated TCP, a connection-oriented protocol. We saw that in order to achieve reliability, TCP sequences and acknowledges every octet. We now understand how, in addition to transporting data, TCP monitors the transmission, and provides not only flow control, but congestion control as well. We also took a closer look at the header, along with the eight control flags, then reviewed how window scaling works.

Along with TCP, we looked at the other predominant transport layer protocol, UDP, which ensures fast transportation of time-sensitive data and protocols such as DHCP and DNS. We reviewed the details of the four-field UDP header, which provides enough information to deliver data with no additional overhead.

Now that you have a solid understanding of TCP, the...