Research On Context Search Based On P2P In Battlefield Environments

With the development of computer, mobile computing, and sensor networks, computing has become ubiquitous. In the digital battlefield environments, because of the complexity, dynamics, heterogeneousness and other characteristics of context data, how to conduct efficient search of context data captured from battlefield environments is a key issue.This paper puts forward an architecture (CSBF) based on peer-to-peer semantic overlay network for context searching. The architecture of UnitPeer in battlefield environments is also proposed. UnitPeer is not only context producer but also context consumer, which is responsible for storage and management of context data captured from various kinds of physical sensors and devices. The study of constucting method of battlefield information ontology is discussed in this paper. An ontology based semantic mapping technique is given to extract semantic infomation from context data and context search request. UnitPeers in semantic cluster are grouped together and organized into Chord ring structure based on the semantic information of their local data. Then, all semantic clusters construct the semantic overlay network based on "small world" network model. CSBF fully makes use of the advantages of structured P2P semantic overlay network, context search requests are only routed to the appropriate aemantic cluster. As a result, the cost of context search can be reduced greatly.At last, the context search algorithm based on CSBF is given and the simulation results demonstrated that, compared with the original Chord network, CSBF has better scalability and more efficient search performance.