In recent years, the use of sensors to measure the biometrics and movements of human body has resulted in the design of wireless body area networks (WBANs). These consist of small, intelligent devices attached on or implanted in the body .The development of such networks is imperative for modern telemedicine and m-health. However, security remains a formidable challenge yet to be dealt with. WBANs have the advantage of the possibility of using random biometric measurements that use an intrinsic characteristic of the human body as the authentication identity or the means of securing the distribution of cipher keys.In this paper, the authors will begin by surveying the most recent research directions in the field. Then, a distributed key management scheme, which makes use of key refreshment schedules, will be proposed to fairly and securely distibute key management responsibility among all nodes. Our scheme supports the use of biometric measurements to generate symmetric keys in WBANs scenario.