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

Reviewing the transport layer

The transport layer of the OSI model is responsible for providing end-to-end data transport, by either using a connectionless or connection-oriented protocol across an IP network. The transport protocol used will depend on the application.

In addition to TCP and UDP, there are several protocols in this layer, including the following:

  • Reliable data protocol (RDP): Used to transfer data in a connection-oriented manner
  • Stream control transmission protocol (SCTP): Provides the reliable transmission of data streams that have more than one IP address

While there are other transport layer protocols, the two predominant protocols are TCP and UDP, as shown in the following figure:

Figure 9.1 – The OSI model—Transport layer

UDP is connectionless and is used when data transport needs to be fast. UDP has a lightweight four-field header that is always 8 bytes in length.

Note

Unlike TCP, UDP currently...