Chapter 5. NetFlow

Overview of NetFlow and Flow-Tools

The traffic analysis tools described so far all produce quantitative information about network traffic: the amount of bandwidth used or the number of transmitted packets per second, for example. However, it is often necessary to have a more qualitative view of traffic. If your network is attacked by a flood of packets, you would like to know something about the data in the packets. You need to know at least enough to block the traffic from your network.

NetFlow is a feature available on some routers that will allow you to view this information. It includes data such as the source and destination IP addresses, source and destination protocol port numbers, number of packets transmitted, number ...

Get Open Source Network Administration now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.