Network Security Principles and Practices

Using ACLs to Stop Denial of Service Attacks

DoS attacks are network attacks in which an attacker tries to reduce the amount of legitimate access to a network by using up that network's resources. These resources could be the bandwidth on the link connecting the target network to the rest of the world or the amount of memory available on a router or server to process incoming connections or other similar resources. Chapter 14, “What Is Intrusion Detection?,” has more details on DoS attacks and some examples.

The following sections present some of the most basic strategies for using ACLs to prevent DoS attacks.

Using ACLs to Stop Traffic from Invalid IP Addresses

There can be quite a few reasons why an attacker forges a source address while staging ...