The Research of Secure Transport Protocol Based on Node's Clock Characteristics for Body Area Networks

The data security and privacy are key issues, as well as the security measures of clinical application are desired to be simple operations of "plug and play" for wireless body area networks (BAN). In this paper; a secure multi-hop data transmission protocol based on combination of node's clock characteristics and properties of the BAN/BSN is presented without relying on any pre-distributed secret information. First, through exchanging clock frequency (CF) among node x, its neighbor i and sink in a safe environment, the pair-wise K-x between node x and sink is generated with CF of x and is used to encrypt data sensed by x; the pair-wise K-xi, or K-ix between x and i is generated with clock skew of two nodes is used to encrypt route information; Second, the RREQ and RREP messages of AODV protocol is improved, and creates a secure route only composed of legal nodes through authenticating nodes with CFs of two adjacent nodes; Finally, the data packet produced by source x is divided into Datal and Data2, Data2 is the being sensed data encrypted with K-x, and Datal encrypted with K-xi, or K-ix includes source, destination, generated time of data and other information, the intermediate node needs to encrypt Datal again after decrypting Datal to obtain route information, and transmits this data packet to sink with hop-by-hop. This protocol has good security in dynamics and accuracy of keys, avoiding passive and active attacks, preventing node capture and supporting new node joining through security analysis, and has accepted overheads of memory, computation and energy consumption by means of performance analysis; it satisfies the requirements of "plug and play" without added node's hardware and pre-load any keys, makes the complicated data security and privacy in the BAN/BSN become operable easily and practicable strongly.