Design And Implementation Of Authentication And Data Encryption In Wireless Body Area Network

With the gradual improvement of living standards,people's demand for medical services and health telemonitoring is also growing.Health monitoring and telemedicine based on WBAN has become one of the research hotspots in the field of wireless communication and medical treatment.WBAN technology can collect human physiological data by reasonably arranging intelligent sensor nodes on the human body surface or in the body,and transmit the collected human physiological data to users or medical staff by wireless.The data were analyzed for health monitoring and medical diagnosis.Due to the network specificity of WBAN and the privacy sensitivity of human physiological data,WBAN is vulnerable to external threats and attacks,which means the protection of private data is particularly important.Combined with IEEE802.15.6 protocol,this thesis studies the security mechanism of WBAN and proposes a security scheme suitable for WBAN.The specific work is summarized as follows:1.Based on the reverse incompatibility of ECDLP in ECC public key cryptosystem,asymmetric encryption technology is used to generate a shared key with high security strength,and then shared key is used for more secure symmetric encryption.According to the NIST standard,the appropriate elliptic curve and its parameters are selected.In the process of hardware circuit design,ECC scalar multiplication algorithm adopts the method of module division from top to bottom and module design from bottom to top to realize scalar multiplication in finite field.Among them,the design implementation of the finite field model inverse operation is based on the properly improved Small Fermat's Theorem.2.This thesis proposes to apply the HMAC-SHA256 algorithm to the authentication mechanism of ‘challenge/response' to complete identity authentication and message integrity authentication.In hardware circuit implementation,according to the characteristic of HMAC-SHA256 algorithm,the circuit design of HMAC-SHA256 is completed by designing SHA256 sub-module.Then introduces the theoretical knowledge of AES256 algorithm,analyzes its algorithm structure,and designs its operation process logically according to each round.Encryption circuit and decryption circuit are realized by module multiplexing to save area and optimize speed.3.According to the IEEE802.15.6 protocol,a security communication scheme suitable for WBAN is proposed.The main process of this scheme is that when the node requests to enter the WBAN,the hub will request to check the node's certificate firstly;Then the they calculate their respective public keys by ECC point multiplication and exchange the public keys to obtain the shared key;The data integrity verification by comparing HMAC value calculated by hub and node respectively;Finally,the shared data is used to symmetrically encrypt and decrypt the information data in the WBAN.The scheme is verified under Modelsim integrated by QuartusII,and the hardware description language Verilog was used to describe and realize the hardware circuit of the whole scheme.