1 Vision, Issues, and Architecture for Nomadic Computing 1 Rajive Bagrodia, Wesley W. Chu, Leonard Kleinrock and Gerald Popek ABSTRACT The pervasive nature of computing and communications is bringing about a paradigm shift in the way these technologies are being used. The shift is in the direction of nomadic computing and communications. Nomadicity refers to the system support needed to provide a rich set of computing and communication capabilities and services to the nomad as he or she moves from place to place in a transparent, integrated and convenient form. This new paradigm is already manifesting itself as users travel to many different locations with laptops, PDA’s, cellular telephones, pagers, etc. In this paper we discuss a vision of nomadicity as well as open issues, architecture and design concerns that must be addressed as we bring about the system support necessary for nomadicity. 1. Introduction Since the beginnings of telecommunication technology, we have witnessed a number of major shifts in the application of communications to the needs of our society and industry. In that process, we have seen the marriage of wireline and wireless technologies, of analog and digital technologies, of voice, data, video, image, fax, graphics, etc., to create a computer- communications infrastructure that spans the globe and serves billions of people. We are now in the midst of an accelerating groundswell in this field of computer- communications in its largest sense (i.e., not simply the wires and networks, but also the infrastructure, the middleware, the applications, the uses and users of the technology) [12]. Witness the fact that the Internet is now a household word. The use of the Worldwide Web (WWW) is growing faster than any other application we have ever witnessed in 25 years of networking (from the day the ARPANET was born at UCLA in September 1969 up to the present); and the WWW is still in its infancy! Most people function in a world where their desktop computing appliance is connected through a corporate or private network to a server located “someplace else” (possibly in a dungeon in some mysterious basement). It is usually assumed that the connectivity provided by this network is reliable and of high bandwidth (typically megabits per second). But, in fact, most of us are nomads, moving between office, home, airplane, hotel, automobile, branch office, conference room, bedroom, etc. In so doing, we often find ourselves decoupled from our “home base” computing and communications environment. As we move around, we find enormous 1 This work was supported by the Advanced Research Projects Agency, ARPA/CSTO DABT-63-C-0080 “Transparent Virtual Mobile Environment-Travler”; N00174-91-C-0107, “Large Scale Filing and Data Management Environments”; ARPA/ISO F30602-94-C-0207A1, “Scalable and Extensible Cooperatiive Information Systems”