On optimization of update propagation in multidatabase systems

We consider the problem of update propagation in a multidatabase environment. Initially, the update propagation strategy is discussed in terms of minimization of the total communication cost of such operation. We indicate that the Steiner Tree is a more suitable model of update propagation than a minimum spanning tree approach. Since the Steiner Tree problem is NP-hard, the update propagation require an application of heuristic method. Subsequently, further optimization in respect of system response time is considered and an algorithm for computation of a propagation strategy, optimal with respect to this criterion is presented and analyzed. The update propagation response time can be improved by selecting a propagation center in the network; an appropriate algorithm is presented.<>