INTERNET - DRAFT Fred L . Templin SRI International 17

This document specifies an intra-site automatic tunneling protocol (ISATAP) for connecting IPv6 hosts and routers (nodes) within predominantly IPv4-based networks. This method is based on an IPv6 aggregatable global unicast address format (described herein) that embeds the IPv4 address of a node within the EUI-64 format interface identifier. This document assumes that, during the IPv4 to IPv6 coexistence and transition phase, many sites will deploy IPv6 incrementally within their IPv4 interior routing domains; especially those sites which have large and complex pre-existing IPv4 infrastructures. Within such sites, the address format and methods described in this document will enable IPv6 deployment for nodes that do not share a common data link with an IPv6 gateway for their site.