Alan J. Dix and Victoria C. Miles

H.C.I. Group, Department of Computer Science,
University of York, Heslington, United Kingdom, YO1 5DD.
E-mail: [email protected]
Tel: (0904) 432778

Controlling the development of different versions of a document can be a complex task, even for a single author to handle. This task is likely to become more complex as the number of authors increases, and more complex still if those authors are distributed geographically with only limited means of communication, such as electronic mail, to connect them. If this last situation makes version control difficult to manage it also makes it very necessary.
This paper looks at the issue of version control comparing single and multiple user situations. The aim is to focus on requirements for version control that will assist asynchronous distributed group writing. The paper concludes with an informal description of MSC, a multiple-source control system which seeks to fulfill these requirements.

Collaborative document writing has as many forms as there are groups of collaborators. For any given group their collaboration may be at a very fine grain, several heads over the same piece of paper, or very coarse, passing complete versions of the document around from person to person. Our design of a group editing environment [Miles et al., 1991b] tries to support both synchronous and asynchronous working, that is whether or not the collaborators are working at the same time. However, like many groupware systems, it is built upon a local area network and assumes rapid communication between the participants' workstations. Although this can support collaboration within the same building and even at different parts of the campus, it cannot support use over a wide area. Much collaborative writing takes place over a wider area, with communication via e-mail or even floppy disk transfer.

This paper discusses some of the issues connected with collaboration where the participants' workstations communicate over slow infrequent channels such as e-mail. In particular, we will be interested in forms of version control, as a major problem for such work is handling contention for shared objects when there is little opportunity for standard techniques such as centralised data, locking or virtual copresence.

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Cooperative work, version control, collaborative writing, computer mediated
communication, shared editors, electronic mail.
Keywords:

Version Control for Asynchronous Group Work

1 Introduction