QoS-based Synergetic Selection Mechanism for Ubiquitous Services

摘要

In ubiquitous stub environment, it is a critical challenge to select an optimal set of devices to supply high quality ubiquitous service and execute continuously under the circumstance of dynamic characteristics of MANET and limited by the devices' capability. Thus, this paper puts forward a mechanism called the Synergetic Selection Mechanism (SSM) for graph-based ubiquitous service. With a hierarchical model, a QoS-based solving model is ed from the layer models and QoS model. Synergetic Selection Mechanism is composed of three modules, namely service launch module, devices synergetic selection module and maintenance module. In consideration of the impact of network-level parameters on services especially in ubiquitous environment, we add a stamp mechanism. The stamp-based mechanism and the time control window are added to the core algorithm of synergetic selection process. The result of the OPNET simulation shows that SSM can quickly choose high quality executive devices and ensure the service continuity and smoothness. Compared with mechanism DTA and SDA, it improves the performance in service readjustment and delay.