ISI, R.C. ATHENA ISI, R.C. ATHENA ISI, R.C. ATHENA ISI, R.C. ATHENA This document extends the KEM-based Authentication for EDHOC draft [I-D.pocero-lake-authkem-edhoc] by defining additional quantum- resistant authentication methods that support combined authentication approaches, where one party authenticates using a KEM-based mechanism and the other using a post-quantum signature scheme.