Caching Location Data in Mobile Networking

Each Location Directory (LD) provides the information to locate the forwarding address of aMobile Host (MH) in a mobile networking system. The LD should be updated when the MH moves from one access zone to another access zone. If an Internet Access Point (IAP) (or base station) could cache some useful LD information entries, then, after receiving a packet from an MH in its access zone, the IAP could check its cached LDandmake an optimal routing decision. With the LD distributed over the Internet Access Points, we avoid Dogleg Routing because we no longer need to forward the packet to theMobile Router (MR) where a master copy of the LD is located. In this paper, we investigate how the LDdata structure is used, updated, and distributed among Mobile Routers, Internet Access Points, and Mobile Hosts. Furthermore, we present our LD design and implementation in the mobile IP network. Wu is supported by an IBM Fellowship. yBhagwat is supported by an IBM Fellowship.