A Declarative Approach to Hardening Services Against QoS Vulnerabilities

The Quality of Service (QoS) in a distributed service-oriented application can be negatively affected by a variety of factors. Network volatility, hostile exploits, poor service management, all can prevent a service-oriented application from delivering its functionality to the user. This paper puts forward a novel approach to improving the reliability, security, and availability of service-oriented applications. To counter service vulnerabilities, a special service detects vulnerabilities as they emerge at runtime, and then hardens the applications by dynamically deploying special components. The novelty of our approach lies in using a declarative framework to express both vulnerabilities and hardening strategies in a domain-specific language, independent of the service infrastructure in place. Thus, our approach will make it possible to harden serviceoriented applications in a disciplined and systematic fashion.