Run time adaptation of UMTS services to available resources

Abstract

The UMTS is setting forth new challenges in terms of integration of end-to-end QoS management. Our approach consists of providing an end-to-end adaptation frame to UMTS commercial services. A commercial service provided to the user should be adapted when selected as well as during its transfer through the different parts of the network. These adaptations are due to the fluctuation of the parameters of the network and the need to adapt the QoS parameters. We then improve QoS management in respect with the contractual commitments, decrease dropped calls rate and optimize resources use by avoiding call rejections and application flow blocking. The four steps of adaptation of our model are guaranteed by an "adaptation bearer service (ABS)" which provides technologies to adapt the media to available resources according to the adaptation mode and the localization of resource limitation. At connection time, the service provider or ASP may ask the ABS to adapt the requested service according to the user contract, profile and preferences. At the border of the DiffServ network, the router asks for ABS to adapt the waiting flow of the commercial service according to network resource availabilities and the same at the border of radio network and finally to the terminal according to available CPU, memory, etc. Our approach is intended to take into account the requirements of mastering the degradation of multimedia services to avoid bad renderings and process a degradation as early as possible. In this paper, we will develop our model, the intended extension and our preliminary ongoing developments. In another respect, those control points constitute a cornerstone to set up the verification of fundamental properties such as synchronisation.