IPv6/IPv4 Protocol Translation in SPIN

To ease the transition of the Internet from IPv4 to IPv6, header translation has been proposed to provide a truly incremental upgrade path. Translating between IPv4 and IPv6 involves two distinct procedures, address translation and protocol translation. The protocol translation procedure indeed depends on the type of address used, but its core concepts and associated issues are generally independent of any address translation mechanism. This paper focuses on the protocol translation aspect and details it using a translator implementation done in the SPIN extensible operating system [1]. Although this specific implementation is discussed, the protocol translation procedure described is fundamental to all IPv6/IPv4 translators.