Hierarchical admission control scheme for supporting mobility in mobile IP

A lot of different researches have been done for guaranteeing quality-of-service (QoS) to the mobile host in the Internet regardless of the attachment points. However, most of the researches concentrate on adopting the integrated service (IntServ) or differentiated service (DiffServ) over the tunneling section between the home agent and the foreign agent. Also, most researches seem to neglect admission control considering handoff and the QoS architecture. In the big picture for QoS, the end-to-end QoS can be guaranteed by combining, intra-domain QoS and inter-domain QoS. So, if it is possible to guarantee intra-domain QoS, inter-domain QoS can be guaranteed by negotiation between domains. We present the intra-domain QoS guarantee mechanism, which can support host mobility. We redefine intra-domain QoS as an interoperation of micro-level QoS and macro-level QoS, considering protocols that support host mobility and currently discussed in IETF Mobile IP WG. For the microlevel QoS, several admission control mechanisms may limit the handoff dropping and cell overload probability in wireless network. But, it is not enough. Whenever the mobile host moves between different subnet, it may be blocked if available bandwidth is not reserved between gateway home agent and current gateway foreign agent. So, new admission control considering mobility in the macro-level QoS has to be developed. In our proposal, bandwidth broker (BB) in DiffServ network performs the admission control based on the available bandwidth between the gateway home agent and the current gateway foreign agent in addition to neighboring gateway foreign agents, where the mobile host may possibly visit during the lifetime of the connection.