The Reliable Packet Transmission Based on PMIPv6 Route Optimization

Route Optimization (RO) is a function to minimize packet transmission delay through the optimal path between routers communicating with each other. Mobile IPv6 (MIPv6) also supports the RO to solve the triangle routing problem. Basic PMIPv6 does not support the RO. Thus, many schemes have been proposed to support RO in PMIPv6. However, these schemes do not consider the out-of-sequence problem, in which packets arrive out of order, which may happen between the existing path and the newly established RO path. This paper proposes a scheme to solve the out-of-sequence problem more precisely and with low cost. Our proposed scheme solves the problem by using the packet sequence number and the time when the problem occurs. In this paper, we compare PMIPv6 supported by the RO and the Out-of-sequence Time Period (OTP) scheme with our proposed scheme via simulation. Evaluation of the performance reveals PMIPv6 supported by the RO had 66 of out-of-sequence packets, and the OTP scheme has 30. However, our proposed scheme does not incur out-of sequence packets. Our proposed scheme guarantees reliable packet transmission by preventing the problem.