The usage of cryptographic algorithms defined by GOST R 34.10-2012 [GOST3410-2012] and GOST R 34.11-2012 [GOST3411-2012] standards for protection of the information is carried out, as a rule, within the cryptographic protocols based on the accompanying algorithms. This memo contains a description of the accompanying algorithms. It defines the pseudorandom functions, the key agreement protocols based on the Diffie-Hellman method, the parameters of elliptic curves, the key derivation functions and the algorithms used for export of keying material.