Multiple concentrator 4over6 optimization in IPv6 access network

IPv6 transition becomes urgent problem restricting the evolution of Internet. A large number of mechanisms were proposed to solve transition problems. Especially, transition methods with IPv4 over IPv6 tunnel in IPv6 access network have been discussed intensely in IETF softwire working group recently. Many 4over6 mechanisms including stateful and stateless solutions have been proposed. This paper focuses on the 40ver6 scenario with multiple tunnel concentrators and proposes an optimization strategy which is based on two well-known stateful 4over6 techniques: dual-stack lite and public 4over6. We firstly bring up the requirements of multi-TC scenario, and then put forward a simple reference model. Then, a general optimization strategy of multi-TC scenario is proposed. Based on the strategy we give the implementation on both dual-stack lite and public 40ver6. The performance of both normal and optimization solution are then evaluated.