This paper is my attempt to answer these questions. I believe that mobile computing represents a true inflection point in Computer Science. It forces us to face new constraints and address new challenges. The problems it generates are deep, and elude easy solution. What we learn in trying to solve these problems can be of considerable value in a much broader context.

This paper presents a new paradigm for nomadic computing over the Internet called universal personal computing (UPC), where mobile users can access computing resources, network services, and personalized computing environments anywhere using any available terminals. The concept of UPC and system design issues are discussed, and the required system architecture capable of managing different mobile objects, i.e., users and terminals, in the UPC environment is presented. Modifications of connection setup procedures between user application programs to enable addressing based on a global user identity are considered.