Research On Key Technologies Of Location Information Security And Localization In Wireless Networks

With the rapid development of wireless communication and computer technology,wireless networks,such as Mobile Ad hoc Networks(MANETs)and Internet of things(Io Ts),are involved in more research,work,life,and many other environments,and these applications are profoundly changing the society and lifestyle of human beings.With the significant development of communication technologies such as the 5th-Generation(5G),location information is becoming more prominent for emerging wireless networks,such as the Internet of things(Io Ts),and the pervasive application of location information promotes the development of networking technology and its applications.The importance of location information makes it one of the most attractive targets of attackers,which threatens the reliability and privacy of location information.On the other hand,the growth of positioning technology results in many different application scenarios,which has brought about mirror errors and security problems.Focus on some critical technologies of wireless localization and the security of location information,the main work and contributions of this dissertation include the following four aspects:Firstly,the attack from Similar Distance Malicious nodes(SDM attack)in MANETs is investigated,and the distance between the real location of the malicious node and the falsified location(claimed location)may be the same or similar in SDM attack.The SDM attack increases the difficulty of detecting malicious nodes by traditional location verification system in some environments(such as the sparse network).In this dissertation,the proposed method utilizes Received Signal Strength(RSS)and radio irregularity to analyze the rationality of the angle between the malicious node and a legitimate neighbor(assistant node).Then the attack to location information in sparse MANETs can be detected without increasing the hardware overhead.In LVS-RI,the detected node broadcasts requests to its neighbors for RSS results.It then estimates the difference between the irregularity coefficients on the detected and the assistant nodes' directions to detect if the claimed location of the detected node is falsified.LVS-RI is suitable for sparse MANETs due to that it can detect the SDM attack with only one assistant node.Simulation results show that without the communication between the detected node and nodes other than the detecting node,LVS-RI,and its Sequential Evaluation version(LVS-RISE)can effectively detect the SDM attack in sparse networks.Secondly,the privacy preservation of location information in MANETs is studied.The attacker may eavesdrop the location information of users through the wireless channel,and most of the existing location privacy protection systems cannot retain the retrievability of location information.The proposed method transforms and retrieves the location of users according to the distance and spatial cloaking so that the privacy of the user's location is preserved while the retrievability of the original location information is retained.Distance and Spatial Cloakingbased Location Privacy Preservation(DSC-LPP)divides the coverage of the Access Point(AP)into several subspaces according to the radial and angular coordinates.Then the location of the user is transformed into a cloaking space to achieve a virtual location.AP or server can retrieve the user's original location based on the virtual location and ranging result.Besides,a redundancy check is designed based on different spatial divisions to increase the accuracy of retrieved locations.The partition of subspaces makes the DSC-LPP suitable for a variety of environments.Theoretical analysis and simulation results show that DSC-LPP based on can preserve the user's location privacy with low computing and communication costs while the high capability of retrieval is retained.Thirdly,mirror error(flipping ambiguity)of localization in Vehicular Ad hoc Networks(VANETs)is investigated.The main reason for mirror error is that the neighbor nodes are arranged in a line or an approximate line.Therefore,mirror error is more likely to occur in VANETs.For instance,the neighbor nodes of a vehicle may be on another road of some intersection as an approximate line.Then the ranging deviation will result in the mirror error of localization.Sequential RSS(S-RSS)and adaptive search can reduce the occurrence of mirrors.Specifically,the user will broadcast requests for ranging results sequentially,and neighbors with enough ranging results will send all the ranging results to the user with corresponding locations and compass information.The user utilizes bounding-box and compass information to determine its adaptive search area,and then the weighted search-based localization algorithm is utilized to estimate the location of the user.Also,the scheme to adjust the transmission power adaptively based on the flow of road is discussed,which can improve the efficiency of the positioning system.Simulation results show that the system based on S-RSS and adaptive search can effectively reduce the occurrence of mirror error and average localization error.Finally,the security of visible light positioning(VLP)is studied.In a VLP system,the user can not receive the beacon of the anchor Light Emitting Diode(LED)directly due to the interference from the attacker.On the other hand,the attacker can forward the beacon it achieved to the user to change the ranging result between the anchor LED and user,and then the positioning result of the user is affected by the attacker.The proposed method detects attacks by checking the consistency of information released by the beacons according to spatiotemporal correlation and coupled dual beacons.Secure Visible Light Positioning based on Spatial-Temporal Correlation(S-VLP)divides the user's coverage into several time zones.The user will send the positioning request to the anchor LEDs.Then,each LED estimates the time zone it falls into and the sending time of the two coupled beacons according to the ranging results and sends the beacons at the corresponding time.The user estimates the time zones of the anchor LED according to the ranging results and the delay of beacons.If the time zone estimated from the ranging result is the same as the time zone estimated from the delay of beacons,the anchor LED is trustworthy.Otherwise,the beacons of the LED anchor will be ignored in the positioning process.The simulation results show that S-VLP can effectively reduce or eliminate the impact of the jamming attack(and similar range-change attacks)on the positioning results.Besides,theoretical analysis shows that,in some cases,S-VLP can detect the dual-way jamming and wormhole-based false beacon/reported location attacks.