Research On Key Technologies Of Survivability In Unattended Wireless Sensor Networks System

The survivability of network system is the ability of a network system to complete critical tasks in time even when the network system is damaged.Unattended Wireless sensor networks(UWSNs)are usually deployed in a hostile and harsh environment,so they are vulnerable to malicious attacks or accidents.Therefore,in recent years,the survivability of UWSNs has become a hot research topic.The key task of UWSNs is the normal transmission of data.Sensor node failure will affect the safety and reliability of data communication.In this paper,the survivability of resource-constrained UWSNs is improved by using survivability enhancing technology(including failed node detection and route reconstruction)in battlefield monitoring network based on UWSNs,and the survivability evaluation scheme for UWSNs is designed.The main researches and innovations are as follows:(1)Detection scheme of failed node in UWSNs systemAiming at the contradiction between resource-constrained in UWSNs system and high energy consumption due to high detection rate,in this paper,a dynamic programming method for failed node detection rate in resource-constrained UWSNs is proposed.A failed node detection model for UWSNs under internal attack is conducted based on the continuous time Markov chain(CTMC)and the epidemiological model.The optimal detection rate is found by dynamic programming equation(Bellman equation).This method can provide guidance for the application of detection technology,and realize the rational use of network resources while improving the detection effect,thereby improving the survivability of the network system.At the same time,it provides early warning for route reconstruction and provides a basis for reliable route construction.(2)Construction method of reconfigurable routing for UWSNs systemAiming at the impact of failed sensor nodes(failures caused by attacks and accidents)on the reliability of data communication in resource-constrained UWSNs,a global optimal reconfigurable routing method based on information-aware is proposed.In this method,the security,energy consumption and load balance of the entire path are comprehensively evaluated by sensing and renewing information of nodes(the state and trust)before each round of data transmission,thus the global optimal route is reconstructed.This method can effectively avoid failed nodes,provide reliable routing for data transmission,and effectively improve the survivability of the network system,which is the network system can still complete key tasks when it is attacked and malfunctioned.(3)Survivability evaluation method for UWSNs systemAiming at the survivability evaluation of UWSNs system,a survivability evaluation method of UWSNs system was designed.The reliability,availability and survivability of a sensor node can be obtained by using the established sensor node survival model in UWSNs.Based on the reliability theory and the actual characteristics of UWSNs,the reliability,availability and survivability of the entire network system are obtained.In particular,the node failures are divided into two cases in the reliability calculation of network system: independent failure and relevant failure,and ? factor model is introduced to model common cause failure.This method realizes the quantification of multiple evaluation indicators and provides a basis for the evaluation of survivability enhancement technology.