The Implementation of Layer-three Site Multihoming Protocol (L3SHIM)

Layer-three SHIM (L3SHIM) protocol is designed to support site multihoming in IPv6 network and now being standardized at SHIM6 working group in IETF. A host or router can have more than two egress interfaces which are connected to a different ISP and configured by distinct IPv6 network prefixes. By using L3SHIM, when an interface is down, another interface can backup for the ongoing connections as it adopts identifier/locator decoupling architecture. Our team is implementing the L3SHIM protocol on Linux based PC using netfilter hooks in the network kernel. We implemented L3SHIM core and REAP component, and verified the feasibility and usefulness of L3SHIM in multi-homed environment by an experiment. We reported the implementation progress to SHIM6 working group in IETF 67th meeting.