Research On Anonymous Authentication Based On Aggregate Signature For Wireless Body Area Networks

Wireless body area networks(WBAN)is a kind of small body-centered wireless network,which is composed of a set of wearable biosensors and a main body(or mobile terminal,such as a mobile phone,PDA,etc.).Wearable sensors in WBAN collect human's physiological information,and transmit physiological information to remote server by mobile terminal,which analyzes the physiological information and provides relevant services for users in WBAN.Wireless body area networks have very broad applications in the field of medical monitoring.Wearable medical sensors collect physiological information which is related to human health such as blood pressure,blood glucose and heart rate,monitor human health for a long time,and provide accurate and timely data for doctor's diagnosis,so that people enjoy the accurate and convenient medical services even at home.It is very important and private for physiological data related to human health to be transmitted in wireless body area networks.However,it uses wireless communication technology to transmit data,where the open environment of wireless communication is vulnerable to malicious attackers.Obviously,these attackers will infringe on the privacy of the users,and even endanger the lives and health of the users.So,to ensure the security of data and servers is the basis and premise of applications of WBAN,and especially it is important to protect the privacy of the users in WBAN.Afterwards,in order to develop large scale WBANs,the effective privacy protection mechanism to protect the security of network information and the privacy of the users must be designed.An anonymous authentication scheme with good performances is able to protect the privacy of the users,and resist the attacks of malicious attackers efficiently.In an anonymous authentication scheme,when the users request the server for authentication,it should ensure that the users' identity information is not leaked,and keep message confidentiality,integrity,timeliness and non-repudiation.This is a hot and difficult research problem in the field of WBAN.Based on the introduction of the characteristics and security requirements of wireless body area networks,this thesis investigates and discusses identity privacy protection problem in wireless body area networks.The main results are as follows:(1)An anonymous aggregate authentication scheme for multi-user in WBAN was proposed.For the application of wireless body area networks in nursing homes,we developed a new system model for WBAN,which can authenticate multiple users simultaneously.This scheme realizes the authentication between the remote server and the users,protects the users' identity privacy,satisfies the anonymity,and establishes the session key between the communication parties.Using the aggregate signature technology,this scheme reduces the authentication cost of the remote server effectively,and greatly reduces communication cost.Our proposed scheme does not use bilinear mapping and no-pairing operation.Through security analysis and complexity comparisons,it shows that the scheme is not only secure and reliable,but also has low computational and communication overhead.(2)A secure anonymous authentication scheme for WBAN was presented.In this scheme,a fully trusted secure hardware was introduced in the medical application model of the typical wireless body area networks.The secure hardware is deployed at the gateway of the remote server,where the secure hardware only executes the pre-loaded programs,and no one can modify them.This scheme makes use of the technology of aggregate signature,where the secure hardware aggregates the users'signatures with other virtual users' valid signatures,so that the remote server can only verify the aggregated signature,instead of single user signature,that is,it realizes the users' anonymity.Since it uses aggregate signature technology to achieve the anonymity,the users do not have to maintain the pseudonym pool.Therefore,it reduces storage and computation cost of the client,and improves the authentication efficiency.In addition,the users sign the request message by using their respective private keys and the remote server's public key.When the remote server verifies the validity of the signature,it must use the correlative private key.This means that only the specified remote server can verify the signature,and thus the system's security is strengthened.