A system for supporting and managing same-time/different-place group interactions

Abstract

This paper describes a user-interface system developed to support group interactions for same-time/different-place cooperative applications. We address three fundamental aspects of these kind of systems: information sharing, coordination and multiuser-interface. The proposed approach defines four types of objects. Contents store application data. Containers are dedicated to organise and structure application data. Connections manage group coordination. And, finally, Monitors are concerned with users awareness of cooperative activities. One important characteristic of the approach is that it identifies and maps into the above objects two basic properties of group interaction support: visibility (public/private information) and durability (durable/transient information). The system eases the design of complex group interaction processes because it defines simple actions that allow programmers and users to define and combine object properties. An example of system usage is given for an application that supports brainstorming activities. KEYWORDS:Group Interaction, CSCW. INTRODUCTIONThe computer support to group interaction consists of three basic functionalities: information sharing, coordination and multiuser-interface. Information sharing allows to establish a common context between individuals, a functionality that requires the specification of a data consistency model. Data consistency can be preserved through concurrency control mechanisms [5][12], e.g. locking, versioning, history, views, etc. Group interaction adds the notion of interdependence [23][13] and coordination [24][22] to information sharing. Interdependence means that, in cooperative settings, activities flow from one individual to another, while coordination introduces the requirement of managing the dependencies between activities. Several coordination mechanisms have been proposed [31], e.g. free mechanisms, that rely on the social protocols established by users and do not control the access to the medium, floorcontrol, semi-formal, based on language and formal mechanisms. The multiuser-interface is responsible for mediating users and the system. The multiuser-interface must define a public space, shared by all users, and maintain visual consistency of objects which are placed in the public space.