Some properties of the DEC mode of operation of block ciphers

In 2021 Technical Committee for Standardization «Cryptography and security Mechanisms» adopted new methodological recommendations, describing the mode of operation for full disk encryption (hereinafter referred to as the DEC mode). This mode is a modification of the CTR mode and takes into account the operating conditions and some features of block-oriented data carriers. In this paper, the cryptographic characteristics of the DEC mode, such as the bound on the number of partition keys generated and the collision probability for the keystream used for sector encryption, are investigated.