A Research On Wireless Channel Key Generation And Implementation Of Prototype System

The basis of secure communication between devices is using the encryption key to encrypt the communication channel.However,under mobile communication scenarios,there are several limitations.First of all,a key management infrastructure is not always available in mobile communication scenarios.In the next place,the computing power and resources of wireless devices is very limited and we can not consume significant amount of them to perform complex calculations.Last but not least,the broadcast nature of wireless channel makes communication security very difficult to be effectively protected.Due to all these factors,the security of wireless communication faces a huge challenge.Wireless channel has several useful properties: temporal variation,channel reciprocity and spatial decorrelation.And these properties constitute the theoretical basis for dynamic key generation,which can be used for dealing with mobile security challenge.However,current wireless channel key generation method exists the following problems: low key generation rate,bad randomness,high mismatch rate and so on.These defects are limiting application of the wireless channel key generation technology.Aimed at these problems,we improve the channel sampling technique and quantization algorithm of single-channel and multi-channel.At the same time,we design and implement public WLAN security enhancement prototype system.The main tasks are described as following: 1.By analyzing current single-channel sampling technique,we find that network layer tool is used to exchange channel probes.First of all,network layer channel probes will result in packet retransmission and validation,which will make the design of match algorithm more complicated and finally led to high mismatch rate.To deal with this problem,we exchange channel probes in data link layer and design corresponding modules.2.By analyzing current multi-channel sampling technique,we find that current technique lacks effective channel samples matching.As a result,we design and implement channel samples matching and filtering logic.3.By comparing two samples concatenating algorithm,we design and implement sub-channel dimension concatenation algorithm.Moreover,we design group quantization algorithm to eliminate the effects of signal strength variation.4.We study the security status of public WLAN,and point out the hidden danger of public WLAN.Then we show two examples of attacks.Meanwhile,we design and implement public WLAN security enhancement prototype system.5.We make an experiment to test the proposed algorithm and prototype of our paper.We analyze the experiment results and compare it with current wireless channel key generation technology.Then we show the effects of our public WLAN enhancement prototype system.