Hop-count filtering : simulation and analysis

Abstract

A denial of service (DoS) attack is an attempt by a person or a group of persons to cripple an online service. This can have serious consequences on companies like Amazon and eBay, which rely on their online availability to do business. Many defense mechanisms have been proposed to thwart DoS attacks. One of these defense mechanisms is called hop-count filtering. Although an attacker can forge any field in the IP header, he or she cannot falsify the number of hops an IP packet takes to reach its destination. This hop-count information can be inferred from the time-to-live value in the IP header. Using a mapping between IP addresses and their hop-counts to an Internet server, the hop-count filtering can distinguish spoofed IP packets from legitimate one. In this research, we will simulate the hop-count filtering using SSFNet. And then we analyze the results to show the efficiency of this technique in protecting against DoS attacks.