This paper describes a scheme to increase the availability of context-aware services in ubiquitous computing environment by managing context information effectively where computational and network resources are insufficient. For the context-aware service, function of overall system and quality of service are also required to be maintained by circulating context information in adequate quality. This scheme manages the context information based on relationship between quality of context and quality of service. This scheme can avoid degradation of available network bandwidth and computational resource caused by circulation of excessive context information. From the initial experimental results using a prototype system of a ubiquitous live streaming video service, we confirm the available network bandwidth and computational resource. It is effectively maintained and recovered by controlling the update frequency of user's location information properly depending on the situation.