PCSM: A Context Sharing Model in Peer-to-Peer Ubiquitous Computing Environment

This paper proposes the peer-to-peer context sharing model (PCSM) which is a ubiquitous computing oriented peer-to-peer context sharing model. Owing to the distribution and limit of resources of the mobile ubiquitous network, the PCSM model constructs a context management framework based on the mechanism of registration-query. Through designing the broadcast messages for available terminals discovery and unicast messages for remote registration, the model implements remote registration of Context Database Agents, and builds up an architecture for sharing and fusing of contexts in a peer-to-peer ubiquitous computing environment to satisfy the requirements of sentient computing applications. In contrast with some current context management systems, the PCSM model partly solves the inherent problem of high cost for communication and storage redundancy through the mechanism of optimization. Besides, the PCSM model enables computing nodes to share contexts, on which the decisions depend. Based on the PCSM model, a prototype of instant messenger with ubiquitous computing ability is provided in the end.