DEVELOPMENT OF AN IMPROVED WINTERNITZ HASH-BASED SIGNATURE ALGORITHM FOR BLOCKCHAIN CRYPTOCURRENCY TRANSACTION SECURITY

Abstract

The Winternitz One Time Signature Scheme is a Hash-based Signature Schemes that is used to secure online communicating devices. The low randomness weakness that exists in the ECDSA makes it easier for an attacker using a quantum algorithm to discover the secret key of a legitimate user. However, the major challenge of the hash-based signature algorithm is the large key and signature sizes as well as high computation time. This research work developed an improved Winternitz One Time Signature (i-WOTS) algorithm that could be used for securing cryptocurrency transactions before the transactions are added to a block in the blockchain. The i-WOTS algorithm uses the randomization technique and exclusive OR (XOR) instead of bit masking operations. The i-WOTS computation time as compared with the default algorithm was 0.73 seconds as against 5.89 seconds. This gives 87.61% improvement over the default algorithm. Comparing i-WOTS with WOTS+ and WOTS-S algorithms, the results indicate that the signature generation was 0.011 seconds which was better than the WOTS+ and WOTS-S with 0.045seconds and 0.025 seconds respectively. The same improvement was noticed in terms of signature verification time of i-WOTS which was 0.11seconds as against the verification time for WOTS+ and WOTS-S which was 0.034 seconds and 0.024 seconds. The time complexity for the i-WOTS algorithm was O(nd). The i-WOTS algorithm could be used on light weight devices such as IoT devices because the computation time for the enhanced algorithm will be fast with less memory consumption.