Lightweight 4over6 Efforts Debuted at IETF 85

IPv4 address exhaustion is a reality. The IETF has been investigating several tunnel-based solutions1 to ease the introduction of IPv6, while continuously offering IPv4 services during the transition period. Dual-Stack Lite2 (DS-Lite), which defines a model for providing IPv4 access over an IPv6 network, 3 aims to better align the costs and benefits of deploying IPv6 in operator’s networks. The DS-Lite model proposes a network address and port translation (NAPT) function in the operator’s network to dynamically assign public IPv4 addresses and ports to internal IPv4 packets.Lightweight 4over64 (Lw4o6) is an optimization of DS-Lite designed to reduce NAPT states in the operator’s network. The underlying idea of Lw4o6 is to relocate the NAPT function from the tunnel concentrator (lwAFTR) to the initiators (lwB4s). The lwB4 element is provisioned with a public IP address and a port set.