Using a Lease to Manage Service Contracts in Service Oriented Architectures

Service-oriented architecture concepts and Web Services specifications allow for an infinite binding between the service requestor and the service provider. This open-ended form of interaction constrains the service provider from changing service contracts, policies and endpoints. Other distributed technologies and protocols such as Jini and DHCP provide for the use of a lease to more easily manage service provider resources and to manage change in the environment more efficiently. This paper introduces the concept of a lease as it applies to service-oriented architectures and the concepts of an active lease which maintains state, and a passive lease to eliminate the need for the service provider to maintain a conversational state between service requestor and service provider. Lastly, this paper identifies the components of a service description that would require a rebinding should the components change, and it explores the impact of an active and a passive lease on several quality attributes.