MOBIHOC

On behalf of the Mobihoc Organizing Committee, it is my pleasure to welcome you to Annapolis, Maryland for the 4th Annual ACM Workshop on Mobile Ad Hoc Networks. We definitely have come a long way from the first offering of this Workshop as a satellite workshop of MobiCom in 2000! This year we had 192 submissions (50% more than last year) from which 27 papers were selected to form the main program. We have continued the tradition of holding a poster session during cocktail and reception hours. This will be an excellent opportunity for young researchers to present their ideas and get feedback from the experts in an informal and convivial setting. We received 19 poster submissions and accepted 10; moreover, we invited 8 more posters from the regular submission pool, for a total of 18 posters.We have been fortunate to lure Dr. Martin Vetterli from the Ecole Politechnique Federale de Lausanne, Suisse, to give the keynote address on "Distributed Processing and Communications: on the Interaction of Source and Channel Coding in Mobile Networks". The topic could have not been more timely. It cuts at the very heart of the most critical issue in ad hoc networks today -- the interaction between layers and the tradeoffs the designers are continually faced with. In Martin's case, it is the tradeoff between communications and processing in the fascinating problem of multi sensor signal (eg, sound and video) processing and fusion.The technical program is of exceptional quality and very well balanced, starting from two tutorial on radio models and antennas, and covering topics from the physical layer (directional antennas) to the middleware (security and resource management). The papers are a good reflection of the emerging applications in ad hoc networking. There is no question that the ad hoc network technology is making rapid advances not only in the traditional military field but also in civilian and commercial applications. In fact, several start ups are now focusing on ad hoc network products, even in the midst of the general dot.com meltdown. I hope you will join me in Annapolis to hear about these new and stimulating trends.