3GPP 24.501 v20.0.0 — the document's own text

9.11.3.54 UE security capability

Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).

The UE security capability information element is used by the UE and by the network to indicate which security algorithms are supported by the UE in N1 mode for NAS security as well as which security algorithms are supported over NR and E-UTRA connected to 5GCN for AS security.

The UE security capability information element is coded as shown in figure 9.11.3.54.1 and table 9.11.3.54.1.

The UE security capability is a type 4 information element with a minimum length of 4 octets and a maximum length of 10 octets.

Octets 5 to 10 are optional. If octet 5 is included, then also octet 6 shall be included.

If the UE does not support any security algorithm for AS security over E-UTRA connected to 5GCN, it shall not include octets 5 and 6. The UE shall not include octets 7 to 10.

If the UE does not support any security algorithm for AS security over E-UTRA connected to 5GCN, and if the network includes octets 7 to 10, then the network shall also include octets 5 to 6.

If the network includes octet 7, then it shall include also octet 8. If the network includes octet 9, then it shall include also octet 10.

8	7	6	5	4	3	2	1
UE security capability IEI	octet 1
Length of UE security capability contents	octet 2
5G-EA0	128-5G-EA1	128-5G-EA2	128-5G-EA3	5G-EA4	5G-EA5	5G-EA6	5G-EA7	octet 3
5G-IA0	128-5G-IA1	128-5G-IA2	128-5G-IA3	5G-IA4	5G-IA5	5G-IA6	5G-IA7	octet 4
EEA0	128-EEA1	128-EEA2	128-EEA3	EEA4	EEA5	EEA6	EEA7	octet 5*
EIA0	128-EIA1	128-EIA2	128-EIA3	EIA4	EIA5	EIA6	EIA7	octet 6*
0	0	0	0	0	0	0	0
Spare	octet 7* -10*

Figure 9.11.3.54.1: UE security capability information element

Table 9.11.3.54.1: UE security capability information element

5GS encryption algorithms supported (see NOTE 1) (octet 3)

5GS encryption algorithm 5G-EA0 supported (octet 3, bit 8)
0				5GS encryption algorithm 5G-EA0 not supported
1				5GS encryption algorithm 5G-EA0 supported

5GS encryption algorithm 128-5G-EA1 supported (octet 3, bit 7)
0				5GS encryption algorithm 128-5G-EA1 not supported
1				5GS encryption algorithm 128-5G-EA1 supported

5GS encryption algorithm 128-5G-EA2 supported (octet 3, bit 6)
0				5GS encryption algorithm 128-5G-EA2 not supported
1				5GS encryption algorithm 128-5G-EA2 supported

5GS encryption algorithm 128-5G-EA3 supported (octet 3, bit 5)
0				5GS encryption algorithm 128-5G-EA3 not supported
1				5GS encryption algorithm 128-5G-EA3 supported

5GS encryption algorithm 5G-EA4 supported (octet 3, bit 4)
0				5GS encryption algorithm 5G-EA4 not supported
1				5GS encryption algorithm 5G-EA4 supported

5GS encryption algorithm 5G-EA5 supported (octet 3, bit 3)
0				5GS encryption algorithm 5G-EA5 not supported
1				5GS encryption algorithm 5G-EA5 supported

5GS encryption algorithm 5G-EA6 supported (octet 3, bit 2)
0				5GS encryption algorithm 5G-EA6 not supported
1				5GS encryption algorithm 5G-EA6 supported

5GS encryption algorithm 5G-EA7 supported (octet 3, bit 1)
0				5GS encryption algorithm 5G-EA7 not supported
1				5GS encryption algorithm 5G-EA7 supported

5GS integrity algorithms supported (see NOTE 2) (octet 4)

5GS integrity algorithm 5G-IA0 supported (octet 4, bit 8)
0				5GS integrity algorithm 5G-IA0 not supported
1				5GS integrity algorithm 5G-IA0 supported

5GS integrity algorithm 128-5G-IA1 supported (octet 4, bit 7)
0				5GS integrity algorithm 128-5G-IA1 not supported
1				5GS integrity algorithm 128-5G-IA1 supported

5GS integrity algorithm 128-5G-IA2 supported (octet 4, bit 6)
0				5GS integrity algorithm 128-5G-IA2 not supported
1				5GS integrity algorithm 128-5G-IA2 supported

5GS integrity algorithm 128-5G-IA3 supported (octet 4, bit 5)
0				5GS integrity algorithm 128-5G-IA3 not supported
1				5GS integrity algorithm 128-5G-IA3 supported

5GS integrity algorithm 5G-IA4 supported (octet 4, bit 4)
0				5GS integrity algorithm 5G-IA4 not supported
1				5GS integrity algorithm 5G-IA4 supported

5GS integrity algorithm 5G-IA5 supported (octet 4, bit 3)
0				5GS integrity algorithm 5G-IA5 not supported
1				5GS integrity algorithm 5G-IA5 supported

5GS integrity algorithm 5G-IA6supported (octet 4, bit 2)
0				5GS integrity algorithm 5G-IA6 not supported
1				5GS integrity algorithm 5G-IA6 supported

5GS integrity algorithm 5G-IA7 supported (octet 4, bit 1)
0				5GS integrity algorithm 5G-IA7 not supported
1				5GS integrity algorithm 5G-IA7 supported

EPS encryption algorithms supported (see NOTE 3) (octet 5)

EPS encryption algorithm EEA0 supported (octet 5, bit 8)
0				EPS encryption algorithm EEA0 not supported
1				EPS encryption algorithm EEA0 supported

EPS encryption algorithm 128-EEA1 supported (octet 5, bit 7)
0				EPS encryption algorithm 128-EEA1 not supported
1				EPS encryption algorithm 128-EEA1 supported

EPS encryption algorithm 128-EEA2 supported (octet 5, bit 6)
0				EPS encryption algorithm 128-EEA2 not supported
1				EPS encryption algorithm 128-EEA2 supported

EPS encryption algorithm 128-EEA3 supported (octet 5, bit 5)
0				EPS encryption algorithm 128-EEA3 not supported
1				EPS encryption algorithm 128-EEA3 supported

EPS encryption algorithm EEA4 supported (octet 5, bit 4)
0				EPS encryption algorithm EEA4 not supported
1				EPS encryption algorithm EEA4 supported

EPS encryption algorithm EEA5 supported (octet 5, bit 3)
0				EPS encryption algorithm EEA5 not supported
1				EPS encryption algorithm EEA5 supported

EPS encryption algorithm EEA6 supported (octet 5, bit 2)
0				EPS encryption algorithm EEA6 not supported
1				EPS encryption algorithm EEA6 supported

EPS encryption algorithm EEA7 supported (octet 5, bit 1)
0				EPS encryption algorithm EEA7 not supported
1				EPS encryption algorithm EEA7 supported

EPS integrity algorithms supported (see NOTE 4) (octet 6)

EPS integrity algorithm EIA0 supported (octet 6, bit 8)
0				EPS integrity algorithm EIA0 not supported
1				EPS integrity algorithm EIA0 supported

EPS integrity algorithm 128-EIA1 supported (octet 6, bit 7)
0				EPS integrity algorithm 128-EIA1 not supported
1				EPS integrity algorithm 128-EIA1 supported

EPS integrity algorithm 128-EIA2 supported (octet 6, bit 6)
0				EPS integrity algorithm 128-EIA2 not supported
1				EPS integrity algorithm 128-EIA2 supported

EPS integrity algorithm 128-EIA3 supported (octet 6, bit 5)
0				EPS integrity algorithm 128-EIA3 not supported
1				EPS integrity algorithm 128-EIA3 supported

EPS integrity algorithm EIA4 supported (octet 6, bit 4)
0				EPS integrity algorithm EIA4 not supported
1				EPS integrity algorithm EIA4 supported

EPS integrity algorithm EIA5 supported (octet 6, bit 3)
0				EPS integrity algorithm EIA5 not supported
1				EPS integrity algorithm EIA5 supported

EPS integrity algorithm EIA6 supported (octet 6, bit 2)
0				EPS integrity algorithm EIA6 not supported
1				EPS integrity algorithm EIA6 supported

EPS integrity algorithm EIA7 supported (octet 6, bit 1)
0				EPS integrity algorithm EIA7 not supported
1				EPS integrity algorithm EIA7 supported

For the UE not supporting any security algorithm for AS security over E-UTRA connected to 5GCN, all bits in octets 5 to 10 are spare and shall be ignored, if the respective octet is received with the information element.For the UE supporting at least one security algorithm for AS security over E-UTRA connected to 5GCN all bits in octets 7 to 10 are spare and shall be ignored, if the respective octet is received with the information element.If the AMF receives any of the octets 7 to 10 (NOTE 5), it shall store the octets as received and include them when sending the UE security capability information element to the UE.
NOTE 1: The code points in octet 3 are used to indicate support for 5GS encryption algorithms for NAS security in N1 mode and support for 5GS encryption algorithms for AS security over NR.NOTE 2: The code points in octet 4 are used to indicate support for 5GS integrity algorithms for NAS security in N1 mode and support for 5GS integrity algorithms for AS security over NR.NOTE 3: The code points in octet 5 are used to indicate support for EPS encryption algorithms for AS security over E-UTRA connected to 5GCN.NOTE 4: The code points in octet 6 are used to indicate support for EPS integrity algorithms for AS security over E-UTRA connected to 5GCN.NOTE 5: The AMF can receive this information element also from another AMF or MME during N1 mode to N1 mode or S1 mode to N1 mode handover preparation.