ENHANCED ENCAPSULATED SECURITY PAYLOAD A NEW MECHANISM TO SECURE INTERNET PROTOCOL VERSION 6 OVER INTERNET PROTOCOL VERSION 4

A considerable amount of time will be needed before each system in the Internet can convert from Internet Protocol version 4 (IPv4) to Internet Protocol version 6 (IPv6). Three strategies have been proposed by the Internet Engineer Task Force (IETF) to help the transition from IPv4 to IPv6 which are dual stack, header translation and tunneling. Tunneling is used when two computers using IPv6 want to communicate with each other and the packet will travel through a region that uses IPv4. To pass through this region, IPv6 packet must be encapsulated in IPv4 packet to have an IPv4 address in order to make it IPv4 routing compatible. Internet Protocol security (IPsec) in transport mode carries the payload of the encapsulating packet as a plain data without any mean of protection. That is, two nodes using IPsec in transport mode to secure the tunnel can spoof the inner payload; the packet will be de-capsulated successfully and accepted. Simulation is conducted based on two scenarios, one with spoofing attack and one without. The outcome proved that proposed mechanism has managed to eliminate spoofing threat in IPv6 over IPv4 tunnel.