Protocols for Adaptive Wireless and Mobile Networking

Thc goal of the Mobilc Nctworking Architecture (Monarch)Proj& at Carnegie Mellon University is to develop networking protocols and protocol interfaces to allow truly seamless wireless and mobile host networking. The scope of our efforts includes protocol design, implementation, performance evaluation, and usage-based validation, spanning areas ranging roughly from portions of the International Standards Organization (ISO) data link layer (layer 2) through the presentation layer (layer 6). In this article, we give a status report of our current work in the Monarch Project, placing it in the context of broader efforts by the Internet mobile networking community. Our work will enable mobile hosts to communicate with each other and with stationary or wired hosts, transparently making the most efficient use of the best network connectivity available to the mobile host at any time. To this end, the networking protocols must support adaptive operation in a number of ways. For example, host mobility means that protocols must be able to adapt packet routing to reach each mobile host in its current location. In addition, different wireless networks, intended, for example, for local-area, metropolitanarea, and wide-area use, make different tradeoffs in factors such as bandwidth, latency, error rate, and usage cost, providing different levels of network connection quality with each wireless networking product or service. Network protocols should be able to adapt in order to optimize use of the best available network connection for each mobile host at any time. Furthermore, in order to allow higher-layer protocols and applications to adapt to these changes in network connection quality, network protocols should be able to provide information to higher layers when such changes take place. We are experimenting with our protocols in the context of the Wireless Andrew infrastructure currently being installed at Carnegie Mellon University [l]. The Wireless Andrew infrastructure builds on the current wired network infrastructure on campus that consists mostly of lO-Mb/s Ethernet