A Multi-tier Ubiquitous Service Discovery Protocol for Mobile Clients

Service discovery and delivery problems have recently been drawing much attention from researchers and practitioners. SLP, Jini, and UPnP are among the few emerging service discovery protocols. Although they seem to provide a good solution to the problem, there is an unaddressed need of more sophisticated location and context-aware service selection, and mobile device support. In this paper, we introduce a multi-tiered 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. Context attributes can express various context information including client device capability, service-specific selection logic, and network condition. We also present the Localized Service Propagation protocol (LSP) for mobile service discovery and advertisement. We describe our architecture, concepts and protocols, and present a performance scalability study of the LSP protocol.