Book Image

Network Analysis using Wireshark Cookbook

By : Yoram Orzach
Book Image

Network Analysis using Wireshark Cookbook

By: Yoram Orzach

Overview of this book

Is your network slow? Are your users complaining? Disconnections? IP Telephony problems? Video freezes? Network analysis is the process of isolating these problems and fixing them, and Wireshark has long been the most popular network analyzer for achieving this goal. Based on hundreds of solved cases, Network Analysis using Wireshark Cookbook provides you with practical recipes for effective Wireshark network analysis to analyze and troubleshoot your network. "Network analysis using Wireshark Cookbook" highlights the operations of Wireshark as a network analyzer tool. This book provides you with a set of practical recipes to help you solve any problems in your network using a step-by-step approach. "Network analysis using Wireshark Cookbook" starts by discussing the capabilities of Wireshark, such as the statistical tools and the expert system, capture and display filters, and how to use them. The book then guides you through the details of the main networking protocols, that is, Ethernet, LAN switching, and TCP/IP, and then discusses the details of application protocols and their behavior over the network. Among the application protocols that are discussed in the book are standard Internet protocols like HTTP, mail protocols, FTP, and DNS, along with the behavior of databases, terminal server clients, Citrix, and other applications that are common in the IT environment. In a bottom-up troubleshooting approach, the book goes up through the layers of the OSI reference model explaining how to resolve networking problems. The book starts from Ethernet and LAN switching, through IP, and then on to TCP/UDP with a focus on TCP performance problems. It also focuses on WLAN security. Then, we go through application behavior issues including HTTP, mail, DNS, and other common protocols. The book finishes with a look at network forensics and how to search and find security problems that might harm the network.
Table of Contents (23 chapters)
Network Analysis Using Wireshark Cookbook
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

Analyzing problems in the NetBIOS protocols


Network Basic Input/Output System (NetBIOS) is a set of protocols developed in the early 1980s for LAN communications. A few years later, it was adopted by Microsoft for their networking over the LAN, and then it was migrated for working over TCP/IP (NetBIOS over TCP/IP, RFCs 1001, and 1002).

In today's networks, NetBIOS provides three services:

  • Name service (port 137) for name registration and name to IP address resolution.

  • Datagram distribution service (port 138) for service announcements by clients and servers.

  • Session service (port 139) for session negotiation between hosts. This is used for accessing files, open directories and so on.

In this chapter, we will get into some common problems with the NetBIOS suite of protocols, and we will learn how to try and solve them. Since the NetBIOS set of protocols is quite complicated, and there are hundreds of scenarios of things that might go wrong, we will try to provide some guidelines for how to...