distributed system

Considered typical structure of the multilevel distributed system, the data transmission problems are analyzed and the graphs can be used for their solution. The criteria for choosing the optimal path search algorithm are chosen. Based on the proposed criteria, the Bellman-Ford algorithm is chosen to find the optimal path in the graph. Used principles of Dirty Flag, CSR (Compressed Sparse Row) and defined time-memory relationship parameters to increase the speed of the algorithm.

The structure and principles of constructing a distributed monitoring and forecasting system for water bodies quality designed to forecast the state of water supply sources in the remote mode are considered. The database of water bodies of Ukraine for storing the received data, including the data from the nongovernment and international organizations, is implemented. The interaction between the distributed subsystems is carried out via the client-server architecture.

The gradual shift from individual to shared service delivery platforms brings distributed service delivery systems to the forefront and the problems associated with their proper functioning. Performance of totally ordered multicasting method was modeled and studied in this paper. The analysis revealed that current realization of the method is not suitable for processing non-FIFO-queue events, thus is not able to function adequately in modern high- intensity flow of service requests. Accordingly, improved method is proposed. The block diagram of this method is depicted in the paper.