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In the Central-server Algorithm, a central-server maintains all the shared data. It services the read requests from other nodes or clients by returning the data items to them. It updates the data on write requests by clients and returns acknowledgment messages. A timeout can be employed to resend the requests in case of failed acknowledgments. Duplicate write requests can be detected by associating sequence numbers with write requests. A failure condition is returned to the application trying to access shared data after several retransmissions without a response.

Although, the central-server algorithm is simple to implement, the central-server can become a bottleneck. To overcome this problem, shared data can be distributed among several servers. In such a case, clients must be able to locate the appropriate server for every data access. Multicasting data access requests is undesirable as it does not reduce the load at the servers compared to the central-server scheme. A better way to distribute data is to partition the shared data by address and use a mapping function to locate the appropriate server.

                
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