A Description of the Travler Project

Operating systems that work well for desktop workstations permanently plugged into a network do not work well for mobile computers that are sometimes connected to a high-speed network, sometimes communicating only by slow and expensive wireless links, and sometimes completely cut off.

The Travler project is developing a new approach to system software for support of mobile computing. This project encompasses many components, including individual software modules, modeling and simulation of the mobile environment, and an integrated system that supports special needs of mobile users. The goal is to provide users of mobile computers with an easy-to-use system which offers the greatest functionality while also disguising difficulties of the mobile environment as much as possible.

The system architecture of SEER, one of the mature components of Travler, is shown in the diagram above. SEER ensures that users of disconnected or poorly connected mobile machines will have needed data stored locally on their machines. It determines what files have been used recently, groups together those files that are related, and automatically caches the groups most likely to be needed on the mobile machine's disk before disconnection. When disconnection occurs, the mobile machine will have all the data its user needs in order to work while on an airplane, or at any location far from the usual work place. SEER predicts user requirements and caches files automatically, without interfering with the user's work.