CERNET Center/Tsinghua University Cisco Systems Cisco Systems CERNET Center/Tsinghua University This note describes a framework for IPv4/IPv6 translation. This is in the context of replacing Network Address Translation - Protocol Translation (NAT-PT), which was deprecated by RFC 4966, and to enable networks to have IPv4 and IPv6 coexist in a somewhat rational manner while transitioning to an IPv6 network. This document is not an Internet Standards Track specification; it is published for informational purposes.