Semantic locking in real-time Internet-based collaborative graphics design systems

To make the real-time collaborative graphics design system more efficient, it is essential that the semantic violation problem be well solved. However, works on semantic preservation are very limited. We present the novel schema of semantic locking to prevent semantic violation. Semantic locks are classified into region lock and object lock to solve semantic violation problems at different level of granularity. Users' intension can be expressed either by attaching comment to the lock explicitly or by making some rules to the lock implicitly. A new approach that can resolve semantic conflict problem efficiently is proposed in this paper. The schema has been tested in the CoDesign system.