Dynamic logical structures: a position statement for managing replicated data

The authors discuss extensions to the grid protocol to improve the fault-tolerance of write operations by using the notions of structured read and write grid quorums. As is the case in the standard quorum protocols, the increased fault-tolerance for write operations is at the increased cost of executing read operations. In order to let users continue using the analogues of the read-one-write-all protocol in the context of a logical structure, they develop reconfiguration protocols for dynamically adapting to failures and recovery. This results in the following dichotomy. Users accesses are through the simple analogues of the read-one-write-all protocol with respect to a logical structure and therefore have low communication cost for read operations. On the other hand, the reconfiguration protocol uses the notion of quorums in the context of a logical structure to ensure high data availability. A similar approach can be applied to the tree protocol.<>