实时协同设计系统中同步过程的研究

Research on concurrency maintainance in real-time collaborative system

作为一类支持人机交互的分布式系统,实时协同设计系统允许多个用户通过网络同步的对同一文档进行编辑。实时性、分布式、用户操作无限制是该系统的3个重要要求,但由于用户的同步操作和网络传输延迟的存在,协同过程中容易产生各种不同步的现象。对由于站点迟到或者非正常退出协同设计系统而引起的同步性问题进行了研究,提出了同步过程,包括主控站点发送同步队列、状态矢量轮询、缺少操作补齐等步骤,解决了站点迟到或非正常退出系统而引起的同步性问题。

As a kind of distributed system that supports human-computer interaction, real-time collaborative design systems should be highlighted in practical implementation. When we are developing a real-time collaborative system, three requirements of real-time, distribution and unconstraint are to be fulfilled. Because of the concurrent operations from the users and the transmission latency of the network, some concurrent problems take place during the collaborative work. During the cause of the collaborative design, ifa site joins the system late, or a site disconnect from the system abnormally and rejoins in, concurrent problems will occur. For this situation, the synchronizing process algorithm is proposed, which includes steps of charging site sends the synchronizing queue, state vectors query around, renew the miss operations. This algorithm ensures the newly joined site maintains the same document state with other sites.