2023-08-28 2025-05-28 John Mattson, Göran Selander, Mališa Vučinić 0-23 Standards Action 24-32767 Expert Review 32768-65535 Private Use 0 Derived OSCORE Master Secret IETF 1 Derived OSCORE Master Salt IETF 2-22 Unassigned 23 Reserved IETF 24 EDHOC as KMP for IEEE 802.15.9 IEEE IEEE Std 802.15.9a 25 EDHOC over CoAP as KMP for IEEE 802.15.9 IEEE IEEE Std 802.15.9a 26-32767 Unassigned 32768-65535 Reserved for Private Use IETF John Mattson, Göran Selander, Mališa Vučinić -65536 to -25 Specification Required -24 to -21 Private Use -20 to 23 Standards Action with Expert Review 24 to 65535 Specification Required -65536 to -25 Unassigned -24 to -21 N/A Reserved for Private Use -20 to -1 Unassigned 0 10, -16, 8, 4, -8, 10, -16 AES-CCM-16-64-128, SHA-256, 8, X25519, EdDSA, AES-CCM-16-64-128, SHA-256 1 30, -16, 16, 4, -8, 10, -16 AES-CCM-16-128-128, SHA-256, 16, X25519, EdDSA, AES-CCM-16-64-128, SHA-256 2 10, -16, 8, 1, -7, 10, -16 AES-CCM-16-64-128, SHA-256, 8, P-256, ES256, AES-CCM-16-64-128, SHA-256 3 30, -16, 16, 1, -7, 10, -16 AES-CCM-16-128-128, SHA-256, 16, P-256, ES256, AES-CCM-16-64-128, SHA-256 4 24, -16, 16, 4, -8, 24, -16 ChaCha20/Poly1305, SHA-256, 16, X25519, EdDSA, ChaCha20/Poly1305, SHA-256 5 24, -16, 16, 1, -7, 24, -16 ChaCha20/Poly1305, SHA-256, 16, P-256, ES256, ChaCha20/Poly1305, SHA-256 6 1, -16, 16, 4, -7, 1, -16 A128GCM, SHA-256, 16, X25519, ES256, A128GCM, SHA-256 7-22 Unassigned 23 Reserved 24 3, -43, 16, 2, -35, 3, -43 A256GCM, SHA-384, 16, P-384, ES384, A256GCM, SHA-384 25 24, -45, 16, 5, -8, 24, -45 ChaCha20/Poly1305, SHAKE256, 16, X448, EdDSA, ChaCha20/Poly1305, SHAKE256 26-65535 Unassigned John Mattson, Göran Selander, Mališa Vučinić -65536 to -25 Specification Required -24 to 23 Standards Action with Expert Review 24 to 65535 Specification Required 0 Signature Key Signature Key 1 Signature Key Static DH Key 2 Static DH Key Signature Key 3 Static DH Key Static DH Key 23 Reserved Reserved John Mattson, Göran Selander, Mališa Vučinić -65536 to -25 Expert Review -24 to 23 Standards Action 24 to 65535 Expert Review -65536 to -1 Unassigned 0 Reserved for success IETF 1 tstr Unspecified error IETF 2 suites Wrong selected cipher suite IETF 3 true Unknown credential referenced IETF 4-22 Unassigned 23 Reserved IETF 24-65535 Unassigned John Mattson, Göran Selander, Mališa Vučinić 0-23 Standards Action with Expert Review 24-65535 Specification Required Padding 0 Randomly generated CBOR byte string RFC9528, Section 3.8.1 1-22 Unassigned 23 Reserved 24-65535 Unassigned Francesca Palombini, Marco Tiloca, Göran Selander less than -65536 Private Use -65536 to -25 Specification Required -24 to 23 Standards Action with Expert Review 24 to 65535 Specification Required greater than 65535 Private Use less than -65536 Reserved for Private Use -65536 to -1 Unassigned 0 CBOR Web Token (CWT) containing a COSE_Key in a 'cnf' claim and possibly other claims. CWT is defined in . 1 CWT Claims Set (CCS) containing a COSE_Key in a 'cnf' claim and possibly other claims. CCS is defined in . 2 X.509 certificate 3 to 65535 Unassigned greater than 65535 Reserved for Private Use