Date Added: Jan 2011
Reprogramming is an essential service for wireless sensor networks. Authenticating reprogramming process is important as sensors need to verify that the code image is truly from a trusted source. There are two ways to achieve authentication: public key based and symmetric key based. Although previous work has shown that public key authentication is feasible on sensor nodes if used sparingly, it is still quite expensive compared to symmetric key based approach. This paper proposes a symmetric key based protocol for authenticating reprogramming process.