4.2.2 EF_IMSI (IMSI)

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

If service n°130 is "available", this file shall not be available.

This EF contains the International Mobile Subscriber Identity (IMSI).

Identifier: ‘6F07’		Structure: transparent			Optional
SFI: ’07’
File size: 9 bytes			Update activity: low
Access Conditions: READ PIN UPDATE ADM DEACTIVATE ADM ACTIVATE ADM
Bytes	Description			M/O		Length
1	Length of IMSI			M		1 byte
2 to 9	IMSI			M		8 bytes

– Length of IMSI

Contents:

– the length indicator refers to the number of significant bytes, not including this length byte, required for the IMSI.

Coding:

– according to TS 24.008 [9].

‑ IMSI

Contents:

– International Mobile Subscriber Identity.

Coding:

– this information element is of variable length. If a network operator chooses an IMSI of less than 15 digits, unused nibbles shall be set to ‘F’.

Byte 2:

b8

B7

b6

B5

b4

b3

b2

b1

1

0

0

Parity

LSB of Digit 1

:

:

MSB of Digit 1

For the parity bit, see TS 24.008 [9].

Byte 3:

		b8	b7	b6	B5	b4	b3	b2	b1
										LSB of Digit 2
										:
										:
										MSB of Digit 2
										LSB of Digit 3
										:
										:
										MSB of Digit 3

etc.