Versioning and concurrency control in a distributed design environment

A design data management method in a distributed design environment is described. This method is based on detecting the difference between the original design data and modified design data. One of the advantages of this method is that the precise difference among versions can be identified. Exploiting this feature, the history of modifications of design data can be traced, and the required storage space can be reduced to less than that needed for previous methods. Another advantage is that efficient concurrency control is achieved by detecting the difference between design data