Sensor networks are often deployed in unattended environments, thus leaving these networks vulnerable to falsedata injection attacks. In a large-scale sensor network individual sensors are subject to security compromises. Numerous authentication schemes have been proposed in the past for protecting communication authenticity and integrity in wireless sensor networks. Most of them however have following limitations: high computation or communication overhead, no resilience to a large number of node compromises, delayed authentication, lack of scalability, etc. To address these issues, we propose message authentication approach which adopts a scalable authentication scheme based on elliptic curvecryptography (ECC). While enabling intermediate nodes authentication, our proposed scheme allows any node to transmit an unlimited number of messages without suffering the threshold problem. In addition, our scheme can also provide message source privacy. Theotrical and simulation results are compared.

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Hop-by-hop Authentication Symmetric-key Cryptosystem Public-key Cryptosystem Source Privacy.