Supporting Intra-Site Automatic Tunnel Addressing Protocol with a Network Processor

Intra Site Automatic Tunneling (ISATAP) is an IPv4 to IPv6 transition mechanism which provides dual stack hosts in an IPv4 site with connectivity to the outer IPv6 world. It enables IPv6 packets to travel through the intra IPv4 network by encapsulating them in IPv4 packets. Network processors are special purpose processors that are designed to process serially incoming packets in parallel using multiple processor cores. This paper presents design and implementation of ISATAP mechanism on Intel's IXP2400 network processor. The implementation performs both control and data layers of an ISATAP router.