The applications of the Wireless Sensor Networks (WSNs) com- prising of resource constrained sensor nodes are increasing day by day. However, the pervasive environments in which the WSNs are deployed and the criticality of the available resources therein make the applicability of the security protocols therein, non-trivial. Amongst various panaceas pursued in research, one of the attrac- tive ones is using privacy homomorphism based secure data ag- gregation. Indeed one can find several algorithms based on either Symmetric Key Cryptography or Asymmetric Key Cryptography in the literature that supports either additive or multiplicative ho- momorphic encryption. In this paper, we attempt to survey the ex- isting algorithms with a view to highlight the characteristics of the same. However not limiting ourselves to only theoretical review of the existing literature, we also implement the algorithms. Our work principally focuses only on the support for confidentiality and pri- vacy, the solutions for supporting message integrity and entity au- thentication are beyond the purview of our survey in this paper.

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Wireless Sensor Networks Secure Data Aggregation Privacy Ho- Momorphism