What is nf-HiPAC?
nf-HiPAC is a full featured packet filter for Linux which demonstrates the power and flexibility of HiPAC. HiPAC is a novel framework for packet classification which uses an advanced algorithm to reduce the number of memory lookups per packet. It is ideal for environments involving large rulesets and/or high bandwidth networks.
nf-HiPAC provides the same rich feature set as iptables ( http://www.iptables.org ), the popular Linux packet filter. The complexity of the sophisticated HiPAC packet classification algorithm is hidden behind an iptables compatible user interface which renders nf-HiPAC a drop-in replacement for iptables. Thereby, the iptables' semantics of the rules is preserved, i.e. you can construct your rules like you are used to. From a user's point of view there is no need to understand anything about the HiPAC algorithm.
The nf-hipac userspace tool is designed to be as compatible as possible to 'iptables -t filter'. It even supports the full power of iptables targets, matches and stateful packet filtering (connection tracking) besides the native nf-HiPAC matches. This makes a switch from iptables to nf-HiPAC very easy. Usually it is sufficient to replace the calls to iptables with calls to nf-hipac for your filter rules.