Abstract:

The development of decentralized systems and blockchain technology have expanded the range of cryptocurrency-based banking services. The main difference from the hierarchical structures of the organizations of the banking sector (national and commercial banks) is the formation of valid nodes ensuring the confirmation of transactions based on the checking and verification of digital signatures and MAC codes. The Bitcoin protocols use the SHA-256 algorithm to form MAC codes, however, the rapid growth of the system leads to significant time costs not only for mining, but also for validation of the formed blocks. The further development of decentralized systems, increase the number of wall-distributors and full nodes forces us to look for new ways to solve a temporary problem based on using different approaches to providing authentication in decentralized systems. The paper discusses the algorithm for generating UMAC message authentication codes using a McEliece’s crypto-code scheme based on the use of universal hashing functions. A reduced UMAC model (mini-UMAC) and a method for statistical analysis of the collision characteristics of the generated message authentication codes are proposed. Using the reduced UMAC model, collisional characteristics of authentication codes are investigated, it is shown that the use of cryptographic transformation (using the AES algorithm) at the final stage of UMAC leads to a violation of the universal hashing characteristics.

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