Key identification techniques for determination of appropriate keys for processing messages in communication systems are provided. In one or more methods, an indicator is assigned to each key pair provisioned in a communication system. The indicator is then sent to one or more network elements or functions in the communication system with a message encrypted with a first part of the key pair corresponding to the indicator. A network element or function receiving the encrypted message determines, based on the indicator, a corresponding second part of the key pair to use to process the encrypted message.