Groupware Infrastructures Saul Greenberg Professor Department of Computer

Groupware Infrastructures Saul Greenberg Professor Department of Computer Science University of Calgary Saul Greenberg

Groupware Infrastructures Goal: • Infrastructure/architecture that allows a developer to program a robust, high quality groupware system with modest effort • Should not get in the way of end users - i. e. , how the system is built is transparent to end users

Typical features Run-time architecture • automatically manage processes, interconnections, and communications • Also: security, robustness, access control, … Groupware programming abstractions • Simple ways (e. g. , API, patterns) that a programmer uses to synchronize interaction events and the data model between processes as well as the views presented across displays Groupware widgets • Let a programmer add generic groupware constructs of value to conference participants Session Management / access control • Mechanisms by which end-users create/join/leave ‘meetings’ and how access to these are restricted/controlled

Basic models Client-Server • usually one centralized server with many connected clients - a connection point to discover who is registered - holds shared resources e. g. , shared state - synchronizes all interactions Client Server Client

Basic models Replicated (Peer to peer) • copy of the program executes at each site • communicates and coordinates directly with other replicas Replica