| Research about Computer Supported Cooperative Design (CSCD for short) has made great achieves recently, especially in last decade. Early research of CSCD mostly discuss the situation under the environment of LAN, but with the greatly development of net techniques, the CSCD environment has been upgrade to WAN and the traditional transaction management lost its predominance little by little, hi these decades, many scientific researchers ameliorated traditional transaction commit mechanism and recovery scheme for the collaborative design, and made lots of efforts. But these investigations mostly emphasized on close system structure, so our research of changing traditional transaction mechanism to open collaborative design environment is timely and necessary.In this article, we first talk about the characters of open environment. Based on traditional Client/Server structure and three-tie structure, we give a kind of open collaborative design structure which contains four layers. We also analyze some traditional transaction mechanism such as: two-phase commit protocol, three-phase commit protocol and one-phase commit protocol. Then, we give a new Open One-Phase Atomic Commit Protocol (O1PC). It solves the problem of site autonomy by adding a participants' list in the coordinator's log, and decreases the cost of transaction blocked and resource wasted by permitting uncommitted data lent to other transactions. Finally, we discuss 01 PC's performance in theory and in experiment respectively.With regard to recovery scheme, the long-time executing, the pre-arranged character and the repeated trial make it more and more complex. We give a recovery method based on savepoint mechanism and log. Because this recovery method has some drawbacks in theprocess of executing a savepoint, so we used fuzzy savepoint to improve it and decreased the spending of executing a savepoint. We also give a method to solve the problems arose by incomplete savepoints.
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