For past few years, more interest has been focused on Wireless Sensor Networks (WSN) due to its wide range of applications in various fields. The WSNs are mainly used for sensing the pollution, monitoring the traffic; secure homeland, hospitals, military etc. These sensor networks face many challenges due to the use of wireless medium for communication which is prone to various types of attacks resulting in loss of information. The security requirements in WSN include four major aspects; data confidentiality, data integrity, data authentication and data freshness. Cryptography is used to cater these requirements. Here, a secure cryptosystem was applied using both Bilinear Pairing and Digital signature for establishing a secure user authentication. This paper proposes an efficient user authentication scheme that facilitates security and privacy protection; enable medical personnel to continuously monitor the health conditions of patients and provide a sophisticated medical care.
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