Description: An algorithm for the formation of a message authentication code UMAC, which is based on the use of universal hashfunctions. The methods of statistical analysis of collision properties of the generated message authentication codes using the reduced model UMAC (mini-UMAC). Researched collision properties of authentication codes. It is shown that the use of a cryptographic transformation (using an algorithm AES) at the final stage UMAC leads to disruption of the properties of universal hashing.
Keywords: hash-function, a universal hash-function algorithm UMAC, mini-UMAC, collision