Scalable Ubiquitous Computing Systems

Speaker: Jon Crowcroft

30th June 2004 , 2pm , Room 519, Claremont Tower

Abstract

We are all acquainted with the Personal Computer. We are less aware of the burgeoning numbers of invisible, embedded computers around us in the fabric of our homes, shops, vehicles and even farms. They help us command, control, communicate, entertain, and commerce, and these invisible computers are far, far more numerous than their desktop cousins. The visible face of computing, the ubiquitous PC, is nowadays generally networked. To date, embedded computing systems have been largely used to replace analog control systems (for reasons of price, performance and reliability). Increasingly, however, we will find systems are integrated into a whole. This will lead to a challenge for Computer Science in the form of system complexity. Complexity is at the core of the skill-set of computer science and engineering, but it is also becoming a key piece of the formalisms used to understand other systems in the natural world, in ecology and biology and in physics. With the Internet as large and organic as it already is, we see a complex set of interactions with graph theory, control theory, economics and game theory, and a number of other disciplines being bought to bear and even extended to understand its behaviour. We also see a set of engineering rules of thumb maturing into design principles, which can be applied to other systems. Some principles already established in the world of Internet-scale engineering give us hope that we can build systems early (and there are many Ubiquitous Computing projects underway in the UK, EU and world today), with some hope that they will work. However, as systems grow, new problems for performance (stability, availability, etc) will emerge. Critical new areas for concern are the control of multiple resources (scheduling for battery life, randomising timing of events to avoid correlated overload, statistical failure tolerance in very large scale sensor systems). Within the timescales of this challenge, components will even start to draw resources (power) directly from their environment (ambient heat, RF etc), and this has hidden consequences (radio opacity in unusual places for example). The more we look at how such systems will be built, the more we see them vanish into the substance (and ether) around us! The core of this challenge then, is to abstract out these engineering design principles, and this will be achieved largely through a process of ``build and learn''. This is a natural complement and sister to the challenge to uncover the Science for Global Ubiquitous Computing, which will have descriptive power. We will have prescriptive solutions (patterns) for the mixed reality environment that will form the next phase of development of cyberspace.