Research And Application On Consistency Maintenance Methods Of Shared Object In CSCW

With the speedy development of Internets and the improvement of global degree, the products design of global enterprises changes from traditional serial design to parallel design and from isolated pattern to collaborative pattern for cutting short the development cost and improving development efficiency. Computer Supported Cooperative Work has become a kind of important products design model which can cut short the design cost and improve design efficiency.Concurrency control is the kernel technology of CSCW, how to maintain consistency of shared object is the key problem in concurrency control. The resolution of the problem on consistency maintenance of shared object is the basis of implementing Real-time Cooperative Work.First, this article introduces the appearance and development of CSCW,then brings forward the definition of CSCW after analyzing the characteristic of CSCW.Following this article introduces central research problems and application fields of CSCW.Then this article analyzes the characteristic of CSCW systems and finds out the main factors which affect system performance,based on these we bring forward the requirement of maintaining the consistency of shared object. Then this article analyzes the existent problems which consistency maintenance model need to resolve. Based on the above research this article puts forward the general consistency maintenance model.This article makes research on lock-based method,Token-Ring-based method and operation-serial-based method,and introduces the running-mechanism and some issues in application course. Based on the above research this article summarizes the strongpoints and disadvantages of these three methods.This article makes deep research on operation-transform-based method,and discusses the key technology in detail.First it introduces the convergence-maintaining-mechanism in operation-transform-based method.Then we design the operation-transform function after analyzing symbols and conceptions of Collaborative Text Editor system.Based on research and analysis we bring forward the GOT algorithm.In the end we use one instance of operation- transform-based method validates the exactness of maintaining the attributes of consistency model.This article makes deep research on multi-version-based method,and discusses the kernel technology in detail. Then we bring forward the combine-rule of operations effect after analyzing symbols and conceptions of Collaborative Graphic Editor system.Based on research and analysis we bring forward the MOVIC algorithm. Then we use one instance of multi-version-based method validates the exactness of maintaining the attributes of consistency model. In the end we introduces the object-identifier-mechanism in multi-version-based method.Based on the above research on the multi-method which can maintain the consistency of shared object, this article puts forward a RBCD(Role-Based Collaborative Design) system which is the main research and innovation fruits. This article discusses the role mechanism in detail, including role-partition and persession-assign of RBCD system and the management about role and permission of RBCD system. Based on the analysis of traditional latecomer-joining mechanism,we bring forword transparent latecomer-joining mechanism.In the end we introduces message-drivering-mechanism,message-redisplay-based synchronization mechanism,collision detection and resolve mechanism.Based on above research we bring forword the maintenance of consistency on shared object algorithm.In the end we give one applied instance which validates the exactness of maintenance of consistency on shared object.