3GPP 24.501 v20.0.0 — the document's own text
9.11.3.10 ABBA
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 ABBA information element is to enable the bidding down protection of security features.
The ABBA information element is coded as shown in figure 9.11.3.10.1 and table 9.11.3.10.1.
The ABBA is a type 4 information element with a minimum length of 4 octets and maximum length of 257 octets.
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | |
|---|---|---|---|---|---|---|---|---|
| ABBA IEI | octet 1 | |||||||
| Length of ABBA contents | octet 2 | |||||||
| ABBA contents | octet 3octet n |
Figure 9.11.3.10.1: ABBA information element
Table 9.11.3.10.1: ABBA information element
| ABBA contents (octet 3-n):indicate set of security features defined for 5GS as described in 3GPP TS 33.501 [24]. |
|---|
| NOTE 1: If the UE receives the ABBA IE with a length that is set to a value of 2 and with a value of 0000H, the UE shall use the length and the contents of the ABBA IE as received from the network.NOTE 2: If the UE receives the ABBA IE with a length that is set to a value larger than 2 or with a value that is different from 0000H, the UE shall use the length and the contents of the ABBA IE as received from the network. |