| Service discovery and delivery problems have recently been drawing much attention from researchers and practitioners. The SLP, Jini, and UPnP are some of the front-runners in this area. Although they seem to provide a good solution to the problem, there is an unaddressed need for more sophisticated mobile, location- and context-aware service selection and mobile device support for service delivery as well as service discovery.;In this dissertation, we introduce a multitiered mobile service discovery architecture that addresses the dynamics and the added requirements of mobility. We introduce the concept of context attribute as an effective, flexible means to exploit relevant context information during the service discovery process. We also present a Class-based Service Propagation protocol (CSP) for global service discovery and advertisement. The CSP protocol guarantees better overall query performance without requiring excessive resource use. Combined, context attributes and CSP protocol guarantee the scalability and effectiveness of service discovery in the presence of popular services (services with a very large number of instances). We describe our architecture, concepts, and protocols, and present a performance scalability study of global service discovery.;Service delivery takes place following the service discovery phase to complete the dynamic service acquisition process. The two phases should be bridged by the client device capability information. As a proof-of-concept prototype, we developed the muJini proxy system that allows a service to be discovered by and presented to any class of target devices using a virtual thin-client architecture. |
