3GPP 24.501 v20.0.0 — the document's own text
9.11.3.34 NAS security algorithms
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
The purpose of the NAS security algorithms information element is to indicate the 5G algorithms to be used for ciphering and integrity protection.
The NAS security algorithms information element is coded as shown in figure 9.11.3.34.1 and table 9.11.3.34.1.
The NAS security algorithms is a type 3 information element with a length of 2 octets.
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | |
|---|---|---|---|---|---|---|---|---|
| NAS security algorithms IEI | octet 1 | |||||||
| Type of ciphering algorithm | Type of integrity protection algorithm | octet 2 |
Figure 9.11.3.34.1: NAS security algorithms information element
Table 9.11.3.34.1: NAS security algorithms information element
| Type of integrity protection algorithm (octet 2, bit 1 to 3) | ||||
|---|---|---|---|---|
| Bits | ||||
| 4 | 3 | 2 | 1 | |
| 0 | 0 | 0 | 0 | 5G integrity algorithm 5G-IA0 (null integrity protection algorithm) |
| 0 | 0 | 0 | 1 | 5G integrity algorithm 128-5G-IA1 |
| 0 | 0 | 1 | 0 | 5G integrity algorithm 128-5G-IA2 |
| 0 | 0 | 1 | 1 | 5G integrity algorithm 128-5G-IA3 |
| 0 | 1 | 0 | 0 | 5G integrity algorithm 5G-IA4 |
| 0 | 1 | 0 | 1 | 5G integrity algorithm 5G-IA5 |
| 0 | 1 | 1 | 0 | 5G integrity algorithm 5G-IA6 |
| 0 | 1 | 1 | 1 | 5G integrity algorithm 5G-IA7 |
| All other values are reserved. | ||||
| Type of ciphering algorithm (octet 2, bit 5 to 7) | ||||
| Bits | ||||
| 8 | 7 | 6 | 5 | |
| 0 | 0 | 0 | 0 | 5G encryption algorithm 5G-EA0 (null ciphering algorithm) |
| 0 | 0 | 0 | 1 | 5G encryption algorithm 128-5G-EA1 |
| 0 | 0 | 1 | 0 | 5G encryption algorithm 128-5G-EA2 |
| 0 | 0 | 1 | 1 | 5G encryption algorithm 128-5G-EA3 |
| 0 | 1 | 0 | 0 | 5G encryption algorithm 5G-EA4 |
| 0 | 1 | 0 | 1 | 5G encryption algorithm 5G-EA5 |
| 0 | 1 | 1 | 0 | 5G encryption algorithm 5G-EA6 |
| 0 | 1 | 1 | 1 | 5G encryption algorithm 5G-EA7 |
| All other values are reserved. |