Shpur O. Increasing the quality of composite services in the networks with service-oriented architecture

The thesis solves an actual scientific problem of improvement the time parameters of composite services while increasing the stability of virtual data center topologies, which are formed by distance vector methods for modern heterogeneous networks with rapid data flow dynamic growth to satisfy the needs in information and communication real-time applications for subscribers. The basic methods of providing services in the networks of service-oriented architecture are analyzed. Established that the mutual operation of IntServ and DiffServ models is the best solution to ensure the required quality when transmitting QoS requests from end to end. For the main criterion of quality of service was chosen transmission delay based on the recommendations of the ITU-T Y.1540. It was established that the formation of the metric components for transmission service there are not captured information about a virtual network structure, leads to deterioration of QoS parameters in the migration aspects of atomic components of the composite service. To improve service quality and reduce routing time, that implicitly depends on the reliability of individual units the methods of service quality parameters improvement in networks with service-oriented architecture were proposed, which consider the stability of the data centers structure and maximizing the productivity of distributed systems in terms of load distribution between the interacting hosts in both local and global levels. This will consider not only features for providing various QoS parameters for different classes of traffic, but also the operator’s policy of the service priorities distribution per the quality level requested by subscriber. In this thesis, has been designed the method of local resources distribution between data centers through consolidation and realignment of flows requests, making it possible to improve the timing parameters of the data transmission process, ensuring the reduction of network device congestion.