4.2.51 EFSTART-HFN (Initialisation values for Hyperframe number)

31.1023GPPCharacteristics of the Universal Subscriber Identity Module (USIM) applicationRelease 17TS

This EF contains the values of STARTCS and STARTPS of the bearers that were protected by the keys in EFKEYS or EFKEYSPS at release of the last CS or PS RRC connection. These values are used to control the lifetime of the keys (see TS 33.102 [13]).

Identifier: ‘6F5B’

Structure: transparent

Mandatory

SFI: ‘0F’

File size: 6 bytes

Update activity: high

Access Conditions:

READ PIN

UPDATE PIN

DEACTIVATE ADM

ACTIVATE ADM

Bytes

Description

M/O

Length

1 to 3

STARTCS

M

3 bytes

4 to 6

STARTPS

M

3 bytes

‑ STARTCS

Contents: Initialisation value for Hyperframe number – CS domain.

Coding: The LSB of STARTCS is stored in bit 1 of byte 3. Unused nibbles are set to ‘F’.

‑ STARTPS

Contents: Initialisation value for Hyperframe number – PS domain.

Coding: As for STARTCS.