Research On Multimedia Communication Based On Middleware Of CSCW System

With the development of Computer Supported Cooperative Work(CSCW), the multimedia technique has become the one of CSCW supported techniques. As computer network technique develop continuously, and CSCW applied field extend gradually, How to realizing multimedia communication in cooperative work system and what kind of model achieving multimedia communication witch all become extremely the problems being resolved.One of the key technique that multimedia information mutually operation involve in the cooperation work system is the multimedia communication technique, Traditional multimedia data chiefly is transmitted on Public Switched Telephone Network(PSTN), and adopts circuit switched technique.Since rapid development of VoIP's technique and packet based switch technique, and Internet being popularized rapidly and IP network based business increasing quickly, there is urgent demand of realizing a new method for multimedia communication on the packet based network, thus ITU-T and IETF formulate separately two criterions SIP and H.323 so as to to resolve the correlation issue.Middleware is major type of foundationalsoftware, belonging to diplex software category. However Distributed of Object middleware which integrates Distributed of Object Computing(DOC) with middleware technique can provide new path of solution.This paper contrasts systematically main techniques of multimedia communication and DOC middleware, and analyze some implementation of H.323 and SIP protocol stack in details, including DOC middleware's pattern. Finally based on above-mentioned theory and made use of H.323 protocol stack,COM,muti-thread techniques and so on,the paper introduce design of MultiMedia Communication Developer's Kit(MMCDK), and complete successfully A/V mutual service module of AeroCSCW.