Remote Cooperation:
CSCW Issues for Mobile and Tele-Workers
Alan Dix and Russell Beale (eds.)

This chapter concerns two groups of workers: the mobile worker using a portable computer whilst travelling or whilst at clients' premises; and the teleworker, working from home or at neighbourhood work centres. These workers are part of a larger organisation and access shared corporate information, and yet they lack the level of communication which would be expected within a normal office environment. In particular their work is often composed of periods of individual work isolated completely from the central information sources interspersed with relatively high bandwidth communications. The means of the latter may range from direct connection of mobile computers to office machines through communication over telephone lines or email links to transfer of media such as floppy disks. In short their communication with colleagues and corporate data is intermittent.

The chapter concentrates on two major areas:

• retrieval - making sure you have the right information when you need it.
• synchronisation - updating shared information in a way which makes sense.

These problems appear identical to those of caching and maintaining data integrity in a standard distributed database. However, there are essential non-functional differences which render traditional solutions inappropriate (although still a source of inspiration). Traditional database mechanisms for caching and synchronising updates are almost totally automatic and of small granularity (in time terms often fractions of seconds), and also the costs of, say, a failed cache are not prohibitive. For distributed work the balance is different. Finding you lack an essential file on your portable computer whilst half way across the Atlantic is a major disaster. Similarly, aborting a transaction which represents a day's home-working is unacceptable.

The chapter examines the balance of these requirements and suggests some directions for future systems both for individual and cooperative distributed work. It will also discuss MSC, a system under development which attempts to address some of the data synchronisation problems for asynchronous collaborative document production.