Alias sctp Version 0.1: SCTP NAT implementation in IPFW

Alias sctp is part the SONATA[1] project to develop and release a BSD licensed implementation of a Network Address Translation (NAT) module that supports the Stream Control Transmission Protocol (SCTP). Traditional address and port number look ups are inadequate for SCTP’s operation. A design of the operational states and packet handling necessary to achieve SCTP functionality are outlined along with the necessary modifications required to integrate it into FreeBSD’s ipfw/libalias NAT system. Alias sctp version 0.1 uses unique verification tag and port numbers for NAT, providing support of global multi-homing, T-flagged packets, logging and statistics, timing, and two association shutdown modes.