Low latency and cost effective handoff based on PBF scheme in hierarchical mobile IPv6

In this paper, an efficient neighbor AR (Access Router) discovery scheme and handoff procedure using neighbor information, called the Pre-Binding Update and Forwarding (PBF) scheme, are proposed. It allows each AR and Mobility Anchor Point (MAP) to know neighboring ARs and MAPs, and therefore, a mobile node (MN) can perform the handoff process in advance, using the proposed handoff mechanism. It is important to note that the Inter-MAP domain handoff improvement of the proposed scheme is up to about 57% and 33% for handoff latency in comparison of the Hierarchical Mobile IPv6 (HMIPv6) and the Hierarchical Mobile IPv6 with Fast handover (F-HMIPv6), respectively. In HMIPv6, the total signaling cost rapidly increases in proportion to the number of Correspondent Nodes (CNs) communicating with the MN. Therefore this is combined with the Inter-MAP forwarding scheme, which operates differently to HMIPv6. It does not transmit the Binding Update (BU) message to the CNs and Home Agent (HA) when the MN moves among adjacent MAPs, after the Pre-BU process for Inter-MAP handoff. The proposed scheme demonstrates superior performance, which the total signaling cost is smaller than that of the HMIPv6 scheme, until 8 forwarding steps. Therefore, it is sufficiently satisfied with the requirements of real-time applications, and seamless communication is expected.