| 摘要 |
Dynamic replication of data under distributed system control to control the utilization of resources in a multi-processing, distributed data base system avoiding a central node maintained control, or synchronization by immediately conforming all copies of an updated data file, is achieved by a distributed access control of peer elements by which, requests for access to data of a specified currency are permitted and conformation of updated data is selectively deferred by use of a control procedure implemented at each node (10, 12, 14) and utilizing a status and control table (in SAC 60, 62, 64) at each node which describes that node's view of the status for shared data items at other nodes. Access, including copying and deletion permission, is granted, when a search of the local table discloses no conflict. If conflict is disclosed, messages are exchanged with all involved nodes until the local table discloses no conflict. |
