Research And Implementation Of CSCW-Based CO-CAD

CSCW (Computer Supported Cooperative Work) emerges as a promising research area in the rapid evolution of information technology. Key issues of CSCW such as communication within the group, concurrency control, group awareness, multi-user interface, session management and etc. are discussed in this thesis. Based on the knowledge of CSCW, a Co-CAD prototype system is realized to check some key solutions.The framework of the prototype system is introduced at first, which contains, from bottom to top, communication environment, component-based tools, AutoCAD plug-in and the single-user AutoCAD. Detail information about the framework is given in the following chapters.Since CSCW applications, which involve multi-users working together, need multicast as its basic communication environment, mechanisms of how IP multicast and reliable multicast work are discussed in this thesis. Then, a priority-based concurrency control algorithm used to ensure consistency of replicated data on Co-CAD participant sites is put forward after studying existing concurrency control algorithms. In order to form a runnable CSCW application system, group awareness and session management are indispensable. Therefore related technologies are also discussed. Applicaton sharing and component-based CSCW development platform are introduced due to their similar features as prototype system.To implement the prototype system, some programming technologies are used, including COM/DCOM, ATL, ObjectARX and NetMeeting SDK. Followed with detail system design, some screen snapshots of the system's running instance are given. Future works about the prototype system are described in the end.