The Research On Hypergraph-based Key Management Protocols For Heterogeneous Sensor Networks

Sensor networks are distributed wireless networks which are constituted byself-organizing tiny nodes. These nodes are integrated by sensors, communicators, dataprocessors and storage units. The sensor networks have some characteristics that thenetworks are limited by computational capability, communication ability, storage capacityand energy. Early research on the sensor networks was based on the homogenous networksmostly. The sensor networks will be deployed on different application scenarios. The nodeability, topology structure and working environment will be different and changing by timewhen the networks are working. So, in briefly, the heterogeneity exists all the time. Thispaper considered that heterogeneity was the natural attribute of the sensor networks.Through fully research and use the heterogeneity which exists objectively in sensornetworks, which can immensely reduce the energy consumption; preferably improve theperformance of the network. The keys are indispensible factors on the security of thenetworks and reliable secure communication. Key management lasts on the whole life of thekeys. So, how to summarize the heterogeneity exists universally in the sensor networks andhow to design a secure and efficient key management protocol are primary and importanttasks.First of all, this paper introduced the related knowledge of the sensor networks and keymanagement. Additionally, it introduced the definition of heterogeneous sensor networks(HSN) in detail, and gave the physical structure model and the logic structure model of theHSN. In the description of the structure model, emphatically elaborated the base stationlayer, the cluster layer and the sensor layer of the HSN’s logic structure model, alsodescribed the function of the nodes and the flow of the data in each layer. These provide astructural basis for the future research.Secondly, this paper summarized various heterogeneous elements at the sensor nodeitself, communication protocol, support technology, application requirements and theexternal environment aspects which exist objectively in the HSN. Further, based onhypergraph and the protocol structure of the sensor networks, the paper classified theheterogeneous elements in three dimensions which are the external environment, support technology and the protocol layer. At the same time, it classified them fine-grained in fivelayers which are physical layer, data link layer, network layer, transport layer and theapplication layer. Through such division, a multi-dimensional, fine-grained schematic plotof HSN’s heterogeneity was obtained. Additionally, a mathematical description of HSN’sheterogeneity was proposed by using hypergraph.Finally, because of the number of sensor nodes, high connectivity of the complexnetwork structure, more control information is required. This will consume more bandwidthof the network and the nodes’ energy. All of these shorten the life of the network. In view ofthis problem, this paper also designed a key management protocol HKMP(Hypergraph-based Key Management Protocol) of HSN by using hypergraph. The design ofthe main idea was abstract the HSN as a hypergraph, which meant a sensor node can beviewed as a vertex and a cluster can be viewed as a hyperedge of a hypergraph. HKMPincluded initial deployment stage, key establishing stage, new node joined stage and nodedeleted stage. The calculation of the cluster key can be completed in only two rounds.Performance analysis showed that the HKMP had good scalability, excellent invulnerabilityand high security.