Secure Medical Data Transmission in Body Area Sensor Networks Using Dynamic Biometrics and Steganography

In this paper, we have used ECG signal for secure key exchange between two nodes of the same Body Sensor Network (BSN). InterPulsed Interval (IPI) of the ECG signal is considered as a biometric characteristic for key generation because of its high randomness, time variance properties and also to avoid interference between the other BSNs. The body sensor node to base station (PDA or Laptop) communication has been secured using the symmetric cryptographic algorithm AES and integrity is checked by using the Message Authentication Code (MAC). Steganography is used for securing the data transfer between base station and medical server. In this work, we have embedded the medical data (Blood Pressure) within the patients? facial image. The face image is selected as a cover image in order to provide authentication. The pixel positions for embedding the medical data are determined by fixing a threshold level (120-126). This threshold value is chosen so as to have high random distribution throughout the image. The results have been shown using MATLAB 7.8.0.