7.1. Key Encapsulation Mechanisms (KEMs)
7.1. Key Encapsulation Mechanisms (KEMs)
| Value | KEM | Nsecret | Nenc | Npk | Nsk | Auth | Reference |
|---|---|---|---|---|---|---|---|
| 0x0000 | Reserved | N/A | N/A | N/A | N/A | yes | RFC 9180 |
| 0x0010 | DHKEM(P-256, HKDF-SHA256) | 32 | 65 | 65 | 32 | yes | [NISTCurves], [RFC5869] |
| 0x0011 | DHKEM(P-384, HKDF-SHA384) | 48 | 97 | 97 | 48 | yes | [NISTCurves], [RFC5869] |
| 0x0012 | DHKEM(P-521, HKDF-SHA512) | 64 | 133 | 133 | 66 | yes | [NISTCurves], [RFC5869] |
| 0x0020 | DHKEM(X25519, HKDF-SHA256) | 32 | 32 | 32 | 32 | yes | [RFC5869], [RFC7748] |
| 0x0021 | DHKEM(X448, HKDF-SHA512) | 64 | 56 | 56 | 56 | yes | [RFC5869], [RFC7748] |
Table 2: KEM IDs
The Auth column indicates if the KEM algorithm provides the AuthEncap()/AuthDecap() interface and is therefore suitable for the Auth and AuthPSK modes. The meaning of all other columns is explained in Section 11.1. All algorithms are suitable for the PSK mode.