In mobile computing environments, distributed applications are provided over the wireless network that is unstable. The goal of our research is to offer service stability by rapid failure detection and recovery by switching to service alternatives. Our platform realizes the Quality of Service management required by each client application through the cooperation of client middleware and the overlay network. This paper describes Adaptive Monitoring (AM), which detects failure rapidly with only a slight addition in network load, and Monitoring Information Notification Protocol (MINP), which transfer failure information efficiently. Experiments on a testbed hosting real Web Services confirm that our system can detect failure and switch to a service alternative within the recovery time demanded by most applications. We also confirm that the proposed method is effective in reducing network load as well as satisfying application requirements.