An innovative approach for designing collaborative applications using OpenDoc: from theory to practice

This paper describes a design approach for distributed systems that combines the pure top-down approach commonly found in protocol specification with the benefits of an incremental and iterative object-oriented design approach for software realization. This approach was defined in the Dutch project Platinum. Within this project an advanced signaling infrastructure has been developed and implemented. It allows users to start-up and manage multimedia calls between multiple parties. A set of generic component applications has also been implemented. The use of the design approach is illustrated by a collaborative editor built on top of these component applications. Further the paper addresses the experience gained in practice, particularly concentrating on the complexity of the design and implementation of distributed systems using state of the art technology, and development tools. The paper also demonstrates the flexibility to build other collaborative editors within this framework.