Header Processing Requirements and Implementation Complexity for IPv4 Routers

header processing, IPV4, IPV6, internet, networking, router performance, packet classification The complexity of IP header processing is commonly believed to be the main limiting factor for router performance. The purpose of this report is to explore header processing requirements for IP routers, identify different implementation alternatives and discuss their complexity. The conclusion of the study is that header processing can be implemented both in software and hardware, and the choice between software and hardware depends on requirements in terms of pricing and performance. Furthermore, we find that most IP header processing operations are relatively simple to implement, although packet classification (address lookup) needs special attention.