Shim6: Reference Implementation, Optimization And Application In IPv6 Transition

Multihoming has been widely adopted in the IPv4 Internet. In the IPv6 based next generation Internet, several IPv6 multihoming solutions have been proposed, and shim6 has become the most promising multihoming approach.This paper studies shim6 from several perspectives, including shim6 protocol implementation, shim6 mechanism optimization and IPv4/IPv6 transition utilizing shim6. In order to provide a shim6 research platform, we implement shim6 protocol on the Linux 2.6 platform, which is one of the first reference implementations in the world. Based on this research platform, we refine the shim6 address switching mechanism, which reduces shim6 address switching time greatly. In addition, we propose an enhanced shim6 security mechanism to defeat reflection-type DoS/DDoS attacks launched from the multihomed site, by preventing source address spoofing in the multihomed site. In order to explore the utilization of shim6 in other research fields, we propose a mechanism called MI46 to optimize IPv4/IPv6 inter-operation using simplified shim6. The experiments proved that, the MI46 algorithm can reduce the burden of the IPv6-relay gateways effectively, and enhance IPv6 access performance.This paper firstly surveys the state of the art in multihoming, drawing a conclusion that shim6 is the most promising IPv6 multihoming solution. Then the paper introduces our linux-based shim6 implementation, presents the enhancements on shim6 protocol, including shim6 address switching mechanism refinement and shim6 security mechanism that prevents source address spoofing in the multihomed site. Finally, we describe the MI46 mechanism that uses shim6 to optimize the IPv4/IPv6 inter-operation.