Embedded Interactive Systems (EIS), Computing Department, Lancaster University

A light-weight component model for peer-to-peer applications

Mobile Peer-to-Peer (P2P) computing applications involve collections of heterogeneous and resource-limited devices (such as PDAs or embedded sensor-actuator systems), typically operated in ad-hoc completely decentralized networks and without requiring dedicated infrastructure support. Short-range wireless communication technologies together with P2P networking capabilities on mobile devices are responsible for a proliferation of such applications, yet these applications are often complex and monolithic in nature due to the lack of lightweight component/container support in these resource-constrained devices.

 

In this paper we describe our lightweight software component model P2Pcomp that addresses the development needs for mobile P2P applications. An abstract, flexible, and high-level communication mechanism among components is developed via a ports concept, supporting protocol independence, location independence, and (a)synchronous invocations; dependencies are not hard-coded in the components, but can be defined at deployment or runtime, providing latebinding and dynamic rerouteability capabilities. Peers can elect to provide services as well as consume them, services can migrate between containers, and services are ranked to support Quality-of-Service choices. Our lightweight container realization leverages the OSGi platform and can utilize various P2P communication mechanisms such as JXTA. A “smart space” application scenario demonstrates how P2Pcomp supports flexible and highly tailorable mobile P2P applications.