Mobile Internet access and QoS guarantees using mobile IP and RSVP with location registers

The mobile IP (MIP) protocol for IP version 4 as being standardized by the Internet community provides continuous Internet connectivity to mobile hosts, without requiring any changes to existing routers and higher-layer applications. We propose an alternative protocol, mobile IP with location registers (MIP-LR) which is closer to the "service node" database approach used in the public switched telephone network (PSTN): before launching a packet to the mobile host, the sender first queries a database to obtain the recipient's current location. MIP-LR is designed for operation in enterprise environments or within logical administrative domains, as it requires a sending host to be aware of which hosts are potentially mobile and implement the MIP-LR protocol. The benefits of MIP-LR are that potentially long routes, called "triangle routes", from the sender to the mobile host are avoided, encapsulation of packets sent to a mobile host is not required, the load on the home network as well as the home and foreign agents is reduced, and there is substantially improved interoperability with protocols such as RSVP for providing QoS guarantees. We carry out a simplified average-case analysis of the costs and benefits of MIP-LR and show it can result in significant reductions in mean network costs compared to MIP.