Network analyzers are utilities that capture data about network traffic patterns.
The analyzer hones in on what is presenting a problem in the network. Just like a doctor uses specific equipment to monitor a patient's heart condition, a network analyzer is used to monitor the condition of the network because it detects and reports problems. As such, businesses use them to track and diagnose network failures.
For example, if you discovered your PC could not connect to a server, you could use a network analyzer to check whether:

1. The PC found a route to the server
2. The PC properly requested services from the server
3. The server replied to the PC

The potential problems the analyzer revealed lead you to the exact point of trouble and, thus a clearer understanding of the problem. Consequently, companies large and small have found the network analyzer helpful to:

1. Analyze network traffic
2. Localize the problem source
3. Capture and analyze individual data packets

The figure below shows the results of an analysis of packets:

A network analyzer is an instrument that measures the network parameters of electrical networks. Network analyzers commonly measure parameters because reflection and transmission of electrical networks are easy to measure at high frequencies, but there are other network parameter sets such as y-parameters, z-parameters, and h-parameters. Network analyzers are often used to characterize two-port networks such as amplifiers and filters, but they can be used on networks with an arbitrary number of ports.
Examples of network analyzers include Sniffer from Network General and Lanalyzer from Novell. In the next lesson, you will learn how to correct IP and host configuration problems.

Click the Quiz link below to test your understanding of network diagnostic tools and analyzers.
Network Diagnostics - Quiz