A method and apparatus are disclosed for using a single credential request (e.g., registered public key or ECQV certificate) to obtain a plurality of credentials in a secure digital communication system having a plurality of trusted certificate authority CA entities and one or more subscriber entities A. In this way, entity A can be provisioned onto multiple PKI networks by leveraging a single registered public key or implicit certificate as a credential request to one or more CA entities to obtain additional credentials, where each additional credential can be used to derive additional public key-private key pairs for the entity A.