Intra-Site Automatic Tunnel Addressing Protocol (ISATAP)

RFC 5214

The Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) connects dual-stack (IPv6/IPv4) nodes over IPv4 networks.  ISATAP views the IPv4 network as a link layer for IPv6 and supports an automatic tunneling abstraction similar to the Non-Broadcast Multiple Access (NBMA) model.