Linux® Routing

Changes from 2.2.x to 2.4.x

The biggest change from the 2.2.x series of kernels to the 2.4.x series, at least as far as networking is concerned, is the migration from ipchains to the Netfilter architecture. Netfilter facilitates a new level of services, including stateful packet filtering and better NAT.

The introduction of Netfilter allows Linux to handle some of the more sophisticated routing through a Linux box. For anyone new to Linux, this is a huge boon with no real drawbacks. For experienced Linux admins, it means learning (again) a new set of tools to manage packet filtering and NAT. Of course, optimists will simply see it as job security and an interesting exercise in extending their current skills.

Stateful inspection of packets increases ...