On the security properties of some sighncryption-mechanisms

Security properties of one class of public key cryptographic mechanisms that is called signcryption is considered. The security properties that foreign researchers believe a signcryption-mechanism should possess are formulated. The evolution of signcryption-mechanisms aimed at creating a mechanism possessing all the required security properties is described using examples. Methods of analysis are proposed, permitting to detect the violation of security properties of some of the considered mechanisms. Adversary models in which signcryption-mechanisms described in the international standard ISO/IEC 29150:2011, turn out to be insecure, are specified, and method of their analysis in specified adversary model is suggested.