ISO IEC 27551:2021 pdf download – Information security, cybersecurity and privacy protection — Requirements for attribute-based unlinkable entity authentication. There is no such preliminary procedure between U and RP, meaning that U and RP are a priori strangers to one another. An attribute-based entity authentication protocol is a sequence of computations and communications among U, RP and AP which, when conducted successfully throughout, results in a state at RP where RP is convinced that a statement made by U about its attributes is correct or not. The purpose of the protocol is to reach that state. The authentication phase is...