This paper presents the implementation of knapsack based Elliptic Curve Cryptography (ECC) for digital signature authentication with message recovery. For any key size, elliptic curve cryptosystem provides greater security when compared to integer factorization and discrete logarithm system. Generally in digital signature, signature (r, s) along with message will be sent to the receiver but in our scheme, signature alone is sent and message will be recovered from (r, s). The strength of knapsack algorithm depends on the selection of the knapsack series. Stern series which reduces the time complexity of the existing system has been used. In our approach, knapsack series alone can be kept secret, but in RSA various domain parameters need to be kept secret. The proposed algorithm is secure against the current attacking mechanisms like key only attacks and message attacks.