A mailbox-based scheme for improving mobile IP performance

Mobile IP route optimization and Mobile IP local registration are two approaches to solve performance problems associated with the base Mobile IP protocol proposed by IETF. The route optimization scheme solves the triangular routing problem by introducing the binding cache concept. The local registration scheme reduces the large overhead for location management by processing the mobile host´s registration request only at a local foreign agent. In this paper, we present a mailbox-based approach to take advantages of both approaches. Each mobile host migrated to a foreign network is associated with a mailbox, which can be decoupled with the owner host, and packets destined to the receiver will be delivered to the mailbox whose address is cached in the sender. Separating mailbox from its owner host allows us to achieve adaptive location management, while at the same time buffering incoming packets in the mailbox located somewhere in the network closer to the receiver reduces the retransmission cost. The dynamic migration of mailbox also eliminates the need of pre-structuring mobility agents into hierarchy which is a necessary in the local registration scheme.