Book Image

Mastering Wireshark 2

By : Andrew Crouthamel
Book Image

Mastering Wireshark 2

By: Andrew Crouthamel

Overview of this book

Wireshark, a combination of a Linux distro (Kali) and an open source security framework (Metasploit), is a popular and powerful tool. Wireshark is mainly used to analyze the bits and bytes that flow through a network. It efficiently deals with the second to the seventh layer of network protocols, and the analysis made is presented in a form that can be easily read by people. Mastering Wireshark 2 helps you gain expertise in securing your network. We start with installing and setting up Wireshark2.0, and then explore its interface in order to understand all of its functionalities. As you progress through the chapters, you will discover different ways to create, use, capture, and display filters. By halfway through the book, you will have mastered Wireshark features, analyzed different layers of the network protocol, and searched for anomalies. You’ll learn about plugins and APIs in depth. Finally, the book focuses on pocket analysis for security tasks, command-line utilities, and tools that manage trace files. By the end of the book, you'll have learned how to use Wireshark for network security analysis and configured it for troubleshooting purposes.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Packt Upsell
Free Chapter
Installing Wireshark 2

ARP analysis

In this section, we'll take a look at how ARP works, resolve addresses from IP to MAC, and also see what ARP issues look like in Wireshark. So what ARP does is resolve the IP addresses, which are layer 3 addresses, to MAC addresses, which are layer 2 addresses—these are addresses that are used on our local Ethernet bus. We need this information in order to construct a frame which encapsulates a packet, so we can send it on to the wire. When a user or an application requests data from a specific IP address on layer 3, our system has to figure out what that MAC address is, if it doesn't already have it in its cache. We can check what MAC addresses our system already knows about in its ARP cache. Just like DNS had a cache of locally known information, ARP is also locally cached.

So what we can do is type the following in a Windows machine:

arp -a

If you press Enter, you'll get a list of all the known IP addresses in layer 3 matched up with the physical addresses, which are the MAC...