26.6.8 Test of ciphering mode setting

3GPP51.010-1Mobile Station (MS) conformance specificationPart 1: Conformance specificationTS

The Ciphering Mode Setting Procedure can be used by the network to trigger the start and stop of stream ciphering.

The SS shall start and synchronize ciphering and deciphering according to 3GPP TS 03.20 / 3GPP TS 33.102, 3GPP TS 33.220. The bit stream shall be generated by algorithm A5 (A5/1, A5/3 and A5/4 as defined by the test case) using the encryption key Kc (A5/1, A5/3) or Kc128 (A5/4).

For test cases using algorithm A5/4 Test USIM as specified in Annex 4A is required.

26.6.8.1 Ciphering mode / start ciphering

26.6.8.1.1 Conformance requirements

1. When the MS receives the CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "start ciphering", the MS starts ciphering and deciphering with the algorithm indicated by the "algorithm identifier" field:

– the MS responds with a CIPHERING MODE COMPLETE message in ciphered mode;

– the ciphering uses the cipher key determined during the authentication procedure.

2. The MS responds to the AUTHENTICATION REQUEST message with an AUTHENTICATION RESPONSE message and continues to use the ciphering key obtained from the previous authentication procedure.

References

3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.7.

26.6.8.1.2 Test purpose

To verify that the MS starts ciphering when it receives a CIPHERING MODE COMMAND message with Cipher Mode Setting = "Start Ciphering". To verify that it continues to use the old cipher key after it receives an AUTHENTICATION REQUEST whilst in ciphered mode.

26.6.8.1.3 Method of test

Initial Conditions

System Simulator:

1 cells, Radio_Link_Timeout set to 64.

Mobile Station:

The MS is in the "idle, updated" state, with a TMSI allocated.

Specific PICS statements

– Support for A5/3 (TSPC_Feat_A53)

PIXIT statements

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is made to originate a call. It shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a CM SERVICE REQUEST. The SS sends an AUTHENTICATION REQUEST and the MS shall answer with AUTHENTICATION RESPONSE. Then the SS sends a CIPHERING MODE COMMAND, ordering the MS to start ciphering with an algorithm supported by the MS. After transmission of this command the SS starts deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in ciphered mode using the cipher key determined during the authentication procedure, and continue to establish the call with a SETUP message. After reception of the CIPHERING MODE COMPLETE the SS starts enciphering.

The SS then sends another AUTHENTICATION REQUEST and the MS shall respond with an AUTHENTICATION RESPONSE. The MS shall continue to use the old cipher key.

Finally the SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

5 minutes, including 1 minute for any necessary operator actions.

Expected Sequence

This sequence is performed for execution counter, K=1 and optionally when the MS supports A5/3 for K=3.

Step

Direction

Message

Comments

1

MS -> SS

CHANNEL REQUEST

Establ. Cause = "Originating Call" NECI not set to 1

2

SS -> MS

IMMEDIATE ASSIGNMENT

3

MS -> SS

CM SERVICE REQUEST

4

SS -> MS

AUTHENTICATION REQUEST

5

MS -> SS

AUTHENTICATION RESPONSE

6

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/K". The SS starts deciphering.

7

MS -> SS

CIPHERING MODE COMPLETE

Sent in ciphered mode using the cipher key determined in between steps 4&5. The SS start enciphering.

8

MS -> SS

SETUP

9

SS -> MS

AUTHENTICATION REQUEST

10

MS -> SS

AUTHENTICATION RESPONSE

New cipher key has been calculated.

Sent in ciphered mode using the cipher key determined in between steps 4&5.

11

SS -> MS

CHANNEL RELEASE

Specific Message Contents

CIPHERING MODE COMMAND

For

K = 1, A5/K = A5/1
K = 3, A5/K = A5/3

26.6.8.2 Ciphering mode / no ciphering

26.6.8.2.1 Conformance requirements

When the MS receives a CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "no ciphering" the MS shall respond in non ciphered mode with a CIPHERING MODE COMPLETE message.

When the CIPHERING MODE COMMAND with Ciphering Mode Setting information element set to "no ciphering" is received as a response to a CM SERVICE REQUEST, the MS shall continue the establishment of the CM service.

References

3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.7.

26.6.8.2.2 Test purpose

To verify that the MS does not start ciphering when it receives a CIPHERING MODE COMMAND message with Cipher Mode Setting = "No Ciphering".

26.6.8.2.3 Method of test

Initial Conditions

System Simulator:

1 cells, Radio_Link_Timeout set to 64.

Mobile Station:

The MS is in the "idle, updated" state, with a TMSI allocated.

Specific PICS statements

PIXIT statements

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is made to originate a call. It shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a CM SERVICE REQUEST. The SS sends an AUTHENTICATION REQUEST and the MS shall answer with an AUTHENTICATION RESPONSE. Then the SS sends a CIPHERING MODE COMMAND, ordering the MS not to start ciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in non-ciphered mode and continue to establish the call with a SETUP message.

Finally the SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

5 minutes, including 1 minute for any necessary operator actions.

Expected Sequence

Step

Direction

Message

Comments

1

MS -> SS

CHANNEL REQUEST

Establ. Cause = "Originating call; NECI not equal to 1.

2

SS -> MS

IMMEDIATE ASSIGNMENT

3

MS -> SS

CM SERVICE REQUEST

4

SS -> MS

AUTHENTICATION REQUEST

5

MS -> SS

AUTHENTICATION RESPONSE

6

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "No Ciphering".

7

MS -> SS

CIPHERING MODE COMPLETE

Sent in non-ciphered mode.

8

MS -> SS

SETUP

11

SS -> MS

CHANNEL RELEASE

Specific Message Contents

None.

26.6.8.3 Ciphering mode / old cipher key

26.6.8.3.1 Conformance requirements

When the MS receives the CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "start ciphering", the MS starts ciphering and deciphering with the algorithm indicated by the "algorithm identifier" field. Also;

– the MS responds with a CIPHERING MODE COMPLETE message in the correct ciphered mode;

– the ciphering shall use the previously stored cipher key;

– in the case of a mobile originating speech call, the MS shall send a SETUP message after the completion of the ciphering procedure.

References

3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.7.

26.6.8.3.2 Test purpose

To verify that the MS uses the stored cipher key when it receives a CIPHERING MODE COMMAND without a preceding authentication procedure.

26.6.8.3.3 Method of test

Initial Conditions

System Simulator:

1 cells, Radio_Link_Timeout = 64.

Mobile Station:

The MS is in the "idle, updated" state, with a TMSI allocated and a known cipher key stored.

Specific PICS statements

– Support for A5/3 (TSPC_Feat_A53)

PIXIT statements

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is made to originate a call. It shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a CM SERVICE REQUEST. The SS sends a CIPHERING MODE COMMAND, ordering the MS to start ciphering with a supported algorithm. After transmission of this command the SS starts deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in the commanded ciphered mode using the stored cipher key and continue to establish the call with a SETUP message. After reception of the CIPHERING MODE COMPLETE the SS starts enciphering.

Finally the SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

5 minutes, including 1 minute for any necessary operator actions.

Expected Sequence

Step

Direction

Message

Comments

1

MS -> SS

CHANNEL REQUEST

Establ. Cause = "Originating Call: NECI not equal to 1.

2

SS -> MS

IMMEDIATE ASSIGNMENT

3

MS -> SS

CM SERVICE REQUEST

4

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering", algorithm A5/1 or A5/3, if supported, is arbitrarily selected. The SS starts deciphering.

5

MS -> SS

CIPHERING MODE COMPLETE

Sent in commanded ciphered mode with the stored cipher key. The SS starts enciphering.

6

MS -> SS

SETUP

7

SS -> MS

CHANNEL RELEASE

Specific Message Contents

None.

26.6.8.4 Ciphering mode / change of mode, algorithm and key

Networks can be implemented that do not have the same ciphering algorithms on all base stations. In such networks changes of algorithms and ciphering mode may occur and calls will fail if MSs incorrectly handle commands or use an incorrect cipher key.

26.6.8.4.1 Conformance requirements

1 When the MS in the "not ciphered" mode, receives a CIPHERING MODE COMMAND message with the Ciphering Mode Setting information element set to "start ciphering", the MS shall load the cipher key stored in the SIM into the ME, use this key to start ciphering and deciphering with the algorithm indicated by the "algorithm identifier" field and, respond with a CIPHERING MODE COMPLETE message.

2 If the last timeslot of the message block containing a CIPHERING MODE COMMAND message occurs at time T, then the MS shall be ready to transmit the CIPHERING MODE COMPLETE message before T+500 ms.

3 When the MS receives an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE after receipt of a CIPHERING MODE COMMAND message, the MS shall perform the assignment, use the commanded mode and/or algorithm on the new channel, and not change the ciphering key.

4 When the MS receives a HANDOVER COMMAND message containing a Cipher Mode Setting IE after receipt of a CIPHERING MODE COMMAND message, the MS shall perform the handover, use the commanded mode and/or algorithm on the new channel, and not change the ciphering key.

5 When the MS in the "ciphered" mode receives a CIPHERING MODE COMMAND message with Cipher Mode Setting IE set to "no ciphering", the MS shall load the cipher key stored in the SIM into the ME, load the cipher key stored in the SIM into the ME, stop ciphering and deciphering and, respond with a CIPHERING MODE COMPLETE message.

6 When the MS receives an AUTHENTICATION REQUEST message, it shall process the challenge information and send back an AUTHENTICATION RESPONSE message to the network. The new ciphering key calculated from the challenge information shall overwrite the previous one and be stored on the SIM before the AUTHENTICATION RESPONSE message is transmitted. The ciphering key stored in the SIM shall be loaded in to the ME when any valid CIPHERING MODE COMMAND is received.

7 When the MS in the not ciphered mode receives a CIPHERING MODE COMMAND message with Cipher Mode Setting IE set to "no ciphering", the MS shall load the cipher key stored in the SIM into the ME, stop ciphering and deciphering and, respond with a CIPHERING MODE COMPLETE message.

8 If a handover fails then the operational parameters used when returning to the old channel are those applied before the HANDOVER COMMAND message was received.

9 If an assignment fails then the operational parameters used when returning to the old channel are those applied before the ASSIGNMENT COMMAND message was received.

References

Conformance requirement 1: 3GPP TS 04.08 / 3GPP TS 44.018 subclauses 3.4.7.2 and 4.3.2.2.

Conformance requirement 2: 3GPP TS 04.13 subclause 5.2.7.

Conformance requirement 3: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.3.1.

Conformance requirement 4: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.4.1.

Conformance requirement 5: 3GPP TS 04.08 / 3GPP TS 44.018 subclauses 3.4.7.2 and 4.3.2.2.

Conformance requirement 6: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 4.3.2.2.

Conformance requirement 7: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.7.2.

Conformance requirement 8: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.4.4.

Conformance requirement 9: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 3.4.3.3.

26.6.8.4.2 Test purpose

1 To verify that when the MS is in the "not ciphered" mode and receives the CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "start ciphering", the MS uses the cipher key stored in the SIM to start ciphering and deciphering with the algorithm indicated by the "algorithm identifier" field and that the MS responds with a CIPHERING MODE COMPLETE message.

2 To verify that the MS is ready to transmit the CIPHERING MODE COMPLETE message before 500 ms after the end of the CIPHERING MODE COMMAND message.

3 To verify that when the MS receives an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE after receipt of a CIPHERING MODE COMMAND message, the MS shall perform the assignment, use the commanded mode and/or algorithm on the new channel, and not change the ciphering key.

4 To verify that when the MS receives a HANDOVER COMMAND message containing a Cipher Mode Setting IE after receipt of a CIPHERING MODE COMMAND message, the MS shall perform the handover, use the commanded mode and/or algorithm on the new channel, and not change the ciphering key

5 To verify that when the MS is in the "ciphered" mode and receives the CIPHERING MODE COMMAND message with Cipher Mode Setting IE set to "no ciphering", the MS loads the cipher key stored in the SIM into the ME, stops ciphering and deciphering and, responds with a CIPHERING MODE COMPLETE message.

6 To verify that the MS responds to an AUTHENTICATION REQUEST message with an AUTHENTICATION RESPONSE message and continues to use the cipher key obtained from the previous authentication procedure.

7 To verify that when the MS is in the "not ciphered" mode and receives the CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "no ciphering", the does not start ciphering or deciphering, but does respond with a CIPHERING MODE COMPLETE message.

8 To verify that when the MS receives a HANDOVER COMMAND message and the handover fails, the MS sends a HANDOVER FAILURE message on the old channel using the old ciphering mode and (if ciphered) the old algorithm and old key.

9 To verify that when the MS receives an ASSIGNMENT COMMAND message and the assignment fails, the MS sends an ASSIGNMENT FAILURE message on the old channel using the old ciphering mode and (if ciphered) the old algorithm and old key.

26.6.8.4.3 Method of test

Initial Conditions

System Simulator:

1 cell, with a legal combination of CCCH_CONF with SDCCH/4s or SDCCH/8s is chosen arbitrarily by the SS.

Mobile Station:

The MS is in the "idle, updated" state, with a TMSI allocated and a known cipher key, K, stored in the SIM.

Specific PICS statements

  • Support for A5/3 (TSPC_Feat_A53)
  • TSPC_Type_xxx (all appropriate power classes)

PIXIT statements

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is paged. The MS shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a PAGING RESPONSE message.

The SS sends a CIPHERING MODE COMMAND, ordering the MS to start ciphering with a supported algorithm. After transmission of this command the SS starts deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in the commanded ciphered mode using the cipher key K. After reception of the CIPHERING MODE COMPLETE the SS starts enciphering. The MS shall be ready to transmit the CIPHERING MODE COMPLETE message before 500 ms after the end of the CIPHERING MODE COMMAND message.

The term "ready to transmit" is defined in 3GPP TS 04.13.

The SS sends an AUTHENTICATION REQUEST message to the MS. Cipher key L is calculated. The MS shall send an AUTHENTICATION RESPONSE message to the SS.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) with the Cipher Mode Setting IE set to "no ciphering". The MS shall transmit the HANDOVER COMPLETE on the commanded channel in non ciphered mode.

The SS sends an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE set to "start ciphering". The MS shall start transmitting on the commanded channel using the commanded algorithm and cipher key K. The MS shall transmit the ASSIGNMENT COMPLETE message.

The SS sends a CIPHERING MODE COMMAND, ordering the MS to stop ciphering. After transmission of this command the SS stops deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in non ciphered mode. After reception of the CIPHERING MODE COMPLETE the SS stops enciphering.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) with the Cipher Mode Setting IE set to "start ciphering". The MS shall transmit the HANDOVER COMPLETE on the commanded channel in ciphered mode using cipher key L and command algorithm.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) with the Cipher Mode Setting IE set to "start ciphering" and the algorithm identifier indicating the algorithm currently in use. The MS shall transmit the HANDOVER COMPLETE on the commanded channel in ciphered mode using the same algorithm as before the handover.

The SS sends an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE set to "no ciphering". The MS shall start transmitting on the commanded channel in non-ciphered mode. The MS shall transmit the ASSIGNMENT COMPLETE message.

The SS sends a CIPHERING MODE COMMAND, containing a Cipher Mode Setting IE set to "no ciphering". The MS shall respond with a CIPHERING MODE COMPLETE message.

The SS sends an AUTHENTICATION REQUEST message to the MS. Cipher key M is calculated. The MS shall send an AUTHENTICATION RESPONSE message to the SS.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) with the Cipher Mode Setting IE set to "start ciphering". The MS shall transmit the HANDOVER COMPLETE on the commanded channel using the commanded algorithm and cipher key L.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) with the Cipher Mode Setting IE set to "no ciphering". The SS does not activate the commanded channel. The MS’s transmissions on the new channel need not be monitored. The MS shall transmit the HANDOVER FAILURE message on the "old" channel using the "old" algorithm and cipher key L and commanded algorithm.

The SS sends an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE set to "start ciphering". The SS does not activate the commanded channel. The MS’s transmissions on the new channel need not be monitored. The MS shall transmit the ASSIGNMENT FAILURE message on the "old" channel using the "old" algorithm and cipher key L.

If the MS only supports one ciphering algorithm then the SS sends a CHANNEL RELEASE message.

If the MS supports more than one ciphering algorithm then the following steps are performed:

The SS sends an ASSIGNMENT COMMAND message containing a Cipher Mode Setting IE set to "start ciphering" and the Algorithm Identifier indicating a different supported algorithm to the one in use. The MS shall start transmitting on the commanded channel using the commanded algorithm. The MS shall transmit the ASSIGNMENT COMPLETE message.

The SS sends a HANDOVER COMMAND (for a finely synchronized intra-BTS handover) containing a Cipher Mode Setting IE set to "start ciphering" and the Algorithm Identifier indicating a different supported algorithm to the one in use. The MS shall transmit the HANDOVER COMPLETE on the commanded channel using the commanded algorithm.

The SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

3 minutes.

Expected Sequence

For MSs that only support one ciphering algorithm, the SS shall use step 61A. For MSs that support more than one ciphering algorithm, the SS shall use step 61B and the subsequent steps.

NOTE: 3GPP TS 04.08 / 3GPP TS 44.018 appears to be unclear as to whether timer T3240 shall or shall not be started as a result of the AUTHENTICATION REQUEST messages sent in steps 8 and 44. To allow a variety of test equipment implementations, the IDENTITY REQUEST messages are included in order to avoid an unexpected expiry of timer T3240 prior to the end of the expected sequence.

Step

Direction

Message

Comments

1

SS -> MS

PAGING REQUEST TYPE 1

2

MS -> SS

CHANNEL REQUEST

3

SS -> MS

IMMEDIATE ASSIGNMENT

To either SDCCH4 or SDCCH8 depending upon CCCH_CONF arbitrarily chosen.

4

MS -> SS

PAGING RESPONSE

5

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering", algorithm arbitrarily selected from those supported by the MS. The SS starts deciphering with the selected algorithm.

6

MS -> SS

CIPHERING MODE COMPLETE

Sent in ciphered mode using key "K", the stored cipher key, and the commanded algorithm. This message shall be ready to be transmitted before 500 ms after the completion of step 5.

7

SS

– The SS starts enciphering using key "K".

8

SS -> MS

AUTHENTICATION REQUEST

Contains a new Ciphering Key Sequence Number which is associated with the new cipher key, "L".

9

MS -> SS

AUTHENTICATION RESPONSE

10

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "No Ciphering".

11

SS

The SS activates the new channel without ciphering.

12

MS -> SS

HANDOVER ACCESS

These four HANDOVER ACCESS messages are

13

MS -> SS

HANDOVER ACCESS

sent on the new channel in non ciphered

14

MS -> SS

HANDOVER ACCESS

mode.

15

MS -> SS

HANDOVER ACCESS

Before completion of the 4 access bursts on the new DCCH, additional access bursts may also be sent on the SACCH

16

MS -> SS

HANDOVER COMPLETE

Sent in non ciphered mode on the new channel.

17

SS -> MS

ASSIGNMENT COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering", with algorithm arbitrarily selected from those supported by the MS.

18

SS

The SS activates the new channel with enciphering and deciphering enabled and using cipher key "K".

19

MS -> SS

ASSIGNMENT COMPLETE

Sent on the new channel in ciphered mode using key "K" and the commanded algorithm.

20

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "No Ciphering". The SS starts receiving in non ciphered mode.

21

MS -> SS

CIPHERING MODE COMPLETE

Sent in non ciphered mode. This message shall be ready to be transmitted before 500 ms after the completion of step 20.

22

SS

The SS starts transmitting in non ciphered mode.

23

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering", with algorithm "X" arbitrarily selected from those supported by the MS.

24

SS

The SS activates the new channel with enciphering and deciphering enabled and using cipher key "L".

25

MS -> SS

HANDOVER ACCESS

These four HANDOVER ACCESS messages are

26

MS -> SS

HANDOVER ACCESS

sent on the new channel in the non ciphered

27

MS -> SS

HANDOVER ACCESS

mode.

28

MS -> SS

HANDOVER ACCESS

Before completion of the 4 access bursts on the new DCCH, additional access bursts may also be sent on the SACCH

29

MS -> SS

HANDOVER COMPLETE

Sent on the new channel in ciphered mode using key "L" and algorithm "X".

30

SS -> MS

IDENTITY REQUEST

31

MS -> SS

IDENTITY RESPONSE

32

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering", with algorithm identifier set to "X".

33

SS

The SS activates the new channel with enciphering and deciphering enabled.

34

MS -> SS

HANDOVER ACCESS

These four HANDOVER ACCESS messages are

35

MS -> SS

HANDOVER ACCESS

sent on the new channel in the non ciphered

36

MS -> SS

HANDOVER ACCESS

mode.

37

MS -> SS

HANDOVER ACCESS

Before completion of the 4 access bursts on the new DCCH, additional access bursts may also be sent on the SACCH

38

MS -> SS

HANDOVER COMPLETE

Sent on the new channel in ciphered mode using algorithm "X".

39

SS -> MS

ASSIGNMENT COMMAND

Includes Cipher Mode Setting IE set to "No Ciphering".

40

SS

The SS activates the new channel without ciphering.

41

MS -> SS

ASSIGNMENT COMPLETE

Sent in non-ciphered mode on the new channel.

42

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "No Ciphering".

43

MS -> SS

CIPHERING MODE COMPLETE

Sent in non ciphered mode. This message shall be ready to be transmitted before 500 ms after the completion of step 42.

44

SS -> MS

AUTHENTICATION REQUEST

Contains a new Ciphering Key Sequence Number which is associated with the new cipher key, "M".

45

MS -> SS

AUTHENTICATION RESPONSE

46

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering", with algorithm "Y" arbitrarily selected from those supported by the MS.

47

SS

The SS activates the new channel with enciphering and deciphering enabled and using cipher key "L".

48

MS -> SS

HANDOVER ACCESS

These four HANDOVER ACCESS messages are

49

MS -> SS

HANDOVER ACCESS

sent on the new channel in the non ciphered

50

MS -> SS

HANDOVER ACCESS

mode.

51

MS -> SS

HANDOVER ACCESS

Before completion of the 4 access bursts on the new DCCH, additional access bursts may also be sent on the SACCH

52

MS -> SS

HANDOVER COMPLETE

Sent on the new channel in ciphered mode using key "L"

53

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "No Ciphering".

54

SS, MS

The SS does not activate the new channel The MS’s transmissions on the new channel need not be monitored.

55

MS -> SS

HANDOVER FAILURE

sent on old channel using algorithm "Y" and key "L".

56

SS -> MS

IDENTITY REQUEST

57

MS -> SS

IDENTITY RESPONSE

58

SS -> MS

ASSIGNMENT COMMAND

Includes Cipher Mode Setting IE set to "No Ciphering".

59

SS, MS

The SS does not activate the new channel The MS’s transmissions on the new channel need not be monitored.

60

MS -> SS

ASSIGNMENT FAILURE

sent on old channel using algorithm "Y" and key "L".

61A

SS -> MS

CHANNEL RELEASE

61B

SS -> MS

ASSIGNMENT COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering", with algorithm "Z" arbitrarily selected from those supported by the MS but different to algorithm "Y".

62B

SS

The SS activates the new channel with enciphering and deciphering enabled.

63B

MS -> SS

ASSIGNMENT COMPLETE

Sent on the new channel in ciphered mode using key "L" and algorithm "Z".

64B

SS -> MS

HANDOVER COMMAND

Includes Cipher Mode Setting IE set to "Start Ciphering" and the algorithm identifier set to "Y".

65B

SS

The SS activates the new channel with enciphering and deciphering enabled.

66B

MS -> SS

HANDOVER ACCESS

These four HANDOVER ACCESS messages are

67B

MS -> SS

HANDOVER ACCESS

sent on the new channel in the non ciphered

68B

MS -> SS

HANDOVER ACCESS

mode.

69B

MS -> SS

HANDOVER ACCESS

Before completion of the 4 access bursts on the new DCCH, additional access bursts may also be sent on the SACCH

70B

MS -> SS

HANDOVER COMPLETE

Sent on the new channel in ciphered mode using key "L" and algorithm "Y".

71B

SS -> MS

CHANNEL RELEASE

Specific Message Contents

ASSIGNMENT COMMAND

Information Element

value/remark

Protocol Discriminator

RR Management.

Skip Indicator

0000

Message Type

00101110

Channel Description

– Channel Type

SDCCH/8 or SDCCH4 (same type as old channel)

– TDMA offset

Chosen arbitrarily, but different to the one in use (SDCCH4), otherwise arbitrary..

– Timeslot Number

Chosen arbitrarily, but different to the one in use (SDCCH8) or Timeslot zero.(SDCCH4)

– Training Sequence Code

5 (same as the BCC).

– Hopping

Single RF channel.

– ARFCN

See table below.

Power Command

– Power level

Chosen arbitrarily but within the range supported by the MS.

Cipher Mode Setting

As specified above.

All other information elements:

Not present.

HANDOVER COMMAND

Information Element

value/remark

Protocol Discriminator

RR Management.

Skip Indicator

0000

Message Type

00101011

Cell Description

– Network Colour Code

1

– Base station Colour Code

5

– BCCH Carrier Number

See table below.

Channel Description

– Channel Type

SDCCH/8 or SDCCH4(same type as old channel)

– TDMA offset

Chosen arbitrarily, but different to the one in use (SDCCH4), otherwise arbitrary.

– Timeslot Number

Chosen arbitrarily, but different to the one in use (SDCCH8) or Timeslot zero.(SDCCH4

– Training Sequence Code

5 (same as the BCC).

– Hopping

Single RF channel.

– ARFCN

See table below.

Handover Reference

– Handover Reference Value

Chosen arbitrarily.

Power Command

– Power level

Chosen arbitrarily, but within the range supported by the MS.

Synchronization Indication

– Synchronization indication

synchronized.

– Report observed time difference

not included.

– Normal cell indication

out of range ignored.

Cipher Mode setting

As specified above.

All other information elements:

Not present.

Band

ARFCN

GSM 450

265

GSM 480

315

GSM 710

467

GSM 750

467

T-GSM 810

467

GSM 850

157

GSM 900

30

DCS 1 800

650

PCS 1 900

650

CIPHER MODE COMMAND

Information Element

value/remark

As default message contents, except:

Cipher Mode Setting

– Algorithm Identifier

As specified above.

– Cipher Mode Set

As specified above.

26.6.8.5 Ciphering mode / IMEISV request

If the MS does not supply the IMEISV when requested, the network will not know whether or not the MS is type approved, i.e. whether or not it has passed any tests.

If the MS supplies its IMEISV when not requested, this may cause calls to systematically fail.

26.6.8.5.1 Conformance requirements

1. When the MS receives the CIPHERING MODE COMMAND message with Cipher Response bit set to "IMEISV shall be included" and the Cipher Mode Setting is “no ciphering”, the MS shall include the IMEISV in the Mobile Identity IE in the CIPHERING MODE COMPLETE message.

2. When the MS receives the CIPHERING MODE COMMAND message with Cipher Response bit set to "IMEISV shall not be included", the MS shall not include the Mobile Identity IE in the CIPHERING MODE COMPLETE message.

3. When the MS receives the CIPHERING MODE COMMAND message with Cipher Response bit set to "IMEISV shall be included" and the Cipher Mode Setting is “Ciphering required”, the MS shall include the IMEISV in the Mobile Identity IE in the CIPHERING MODE COMPLETE message.

4. When the MS receives a IDENTITY REQUEST message with ciphering enabled and the Identity Type IE set to “IMEISV”, the MS shall return its IMEISV in the Mobile Identity IE contained within the IDENTITY RESPONSE message.

5. To verify that the SVN portion of the IMEISV value returned by the MS is coded using binary coded decimal digits and does not use the reserved value “99”.

References

Conformance requirement 1: 3GPP TS 04.08 / 3GPP TS 44.018 subclauses 3.4.7.2 and 9.1.10.1.

Conformance requirement 2: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 9.1.10.1.

Conformance requirement 3: 3GPP TS 04.08 / 3GPP TS 44.018 subclause 9.1.10.1.

Conformance requirement 4: 3GPP TS 24.008 subclauses 4.4.3.1, 4.7.1.2 and 4.7.8

Conformance requirement 5: 3GPP TS 23.003 subclause 6.2.2 / 3GPP TS 24.008 table 10.5.1.4

26.6.8.5.2 Test purpose

To verify that the MS supplies its IMEISV in the CIPHERING MODE COMPLETE message when it receives a CIPHERING MODE COMMAND message with a Cipher Response bit set to "IMEISV shall be included" and ciphering is not active/required.

To verify that the MS does not supply any Mobile Identity IE in the CIPHERING MODE COMPLETE message when it receives a CIPHERING MODE COMMAND message with a Cipher Response bit set to "IMEISV shall not be included".

To verify that the MS supplies its IMEISV in the CIPHERING MODE COMPLETE message when it receives a CIPHERING MODE COMMAND message with a Cipher Response bit set to "IMEISV shall be included" and ciphering is active/required.

To verify that the MS supplies its IMEISV in the IDENTITY RESPONSE message when it receives a IDENTITY REQUEST message with the Identity Type IE set to "IMEISV". The IDENTITY REQUEST and IDENTITY RESPONSE messages should not be ciphered (refer to 3GPP TS 24.008 clause 4.7.1.2).

To verify that the MS codes the SVN portion of the IMEISV using binary coded decimal (BCD) digits and does not use the reserved value “99”.

26.6.8.5.3 Method of test

Initial Conditions

System Simulator:

1 cell.

Mobile Station:

The MS is in the "idle, updated" state, with a TMSI allocated.

Specific PICS statements

PIXIT statements

– IMEISV of the MS.

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is paged. It shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a PAGING RESPONSE. Then the SS sends a CIPHERING MODE COMMAND indicating "No ciphering" and with the Cipher Response bit set to "IMEISV shall not be included". The MS shall respond with a CIPHERING MODE COMPLETE message that does not include the Mobile Identity IE.

Then the SS sends a CIPHERING MODE COMMAND indicating "No ciphering" and with the Cipher Response bit set to "IMEISV shall be included". The MS shall respond with a CIPHERING MODE COMPLETE message that carries the IMEISV in the Mobile Identity IE. The SS checks the IMEISV value and verifies that the SVN IE is coded using BCD and does not equal the reserved value “99”.

The SS sends an IDENTITY REQUEST message with the Identity Type IE set to request the IMEISV value from the MS. The MS shall respond with an IDENTITY RESPONSE message that carries the IMEISV in the Mobile Identity IE. The SS then checks the IMEISV value and verifies that the SVN IE is coded using BCD and does not equal the reserved value “99”.

The IDENTITY REQUEST and IDENTITY RESPONSE messages shall not be ciphered.

The SS sends a third CIPHERING MODE COMMAND indicating "ciphering required" and with the Cipher Response bit set to "IMEISV shall be included". The MS shall respond with a CIPHERING MODE COMPLETE message that carries the IMEISV in the Mobile Identity IE. The SS checks the IMEISV value and verifies that the SVN IE is coded using BCD and does not equal the reserved value “99”..

Finally the SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

20 s.

Expected Sequence

Step

Direction

Message

Comments

1

SS -> MS

PAGING REQUEST TYPE 1

2

MS -> SS

CHANNEL REQUEST

3

SS -> MS

IMMEDIATE ASSIGNMENT

4

MS -> SS

PAGING RESPONSE

5

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "No Ciphering".

Cipher Response = "IMEISV shall not be included".

6

MS -> SS

CIPHERING MODE COMPLETE

Shall not include Mobile Identity IE.

7

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "No Ciphering".

Cipher Response = "IMEISV shall be included".

8

MS -> SS

CIPHERING MODE COMPLETE

Shall include one Mobile Identity IE carrying the MS’s IMEISV.

The SS checks the IMEISV value is coded in BCD digits and does not equal 99.

9

SS -> MS

IDENTITY REQUEST

Identity Type = “IMEISV”

The IDENTITY REQUEST message shall not be ciphered.

10

MS -> SS

IDENTITY RESPONSE

Shall include Mobile Identity IE carrying the MS’s IMEISV.

The SS checks the IMEISV value is coded in BCD digits and does not equal 99.

The IDENTITY RESPONSE message shall not be ciphered.

11

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering".

Cipher Response = "IMEISV shall be included".

12

MS -> SS

CIPHERING MODE COMPLETE

Shall include one Mobile Identity IE carrying the MS’s IMEISV.

The SS checks the IMEISV value is coded in BCD digits and does not equal 99. The SVN portion of the IMEISV shall not be ciphered.

13

SS -> MS

CHANNEL RELEASE

Specific Message Contents

None.

26.6.8.6 Ciphering mode / Non support of algorithm A5/2

26.6.8.6.1 Conformance requirements

For the MS it is prohibited to implement algorithm A5/2.

References

3GPP TS 43.020 subclause 4.9

26.6.8.6.2 Test purpose

To verify that the MS does not start ciphering when it receives a CIPHERING MODE COMMAND message with Cipher Mode Setting = "Start Ciphering" and algorithm identifier set to "A5/2".

26.6.8.6.3 Method of test

Initial Conditions

System Simulator:

1 cell. ATT=1.

Mobile Station:

Power off.

Specific PICS statements

PIXIT statements

Test Procedure

The MS is powered on. The MS sends CHANNEL REQUEST for doing location update procedure. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a LOCATION UPDATING REQUEST. SS checks that MS does not support A5/2 algorithm by CLASSMARK ENQUIRY Procedure. Then SS sends an AUTHENTICATION REQUEST and the MS shall answer with AUTHENTICATION RESPONSE. Then the SS sends a CIPHERING MODE COMMAND, ordering the MS to start ciphering with algorithm A5/2 which is prohibited for the MS. After transmission of this command the SS starts deciphering. The MS shall not respond with a CIPHERING MODE COMPLETE message in ciphered mode using the cipher key determined during the authentication procedure.

Maximum Duration of Test

3 minutes, including 1 minute for any necessary operator actions.

Expected Sequence

Step

Direction

Message

Comments

MS is switched on or powered on

1

MS -> SS

CHANNEL REQUEST

2

SS -> MS

IMMEDIATE ASSIGNMENT

3

MS -> SS

LÖCATION UPDATING REQUEST

4

SS->MS

CLASSMARK ENQUIRY

CLASSMARK CHANGE message is requested

5

MS->SS

CLASSMARK CHANGE

A5/2 algorithm = “encryption algorithm A5/2 not available” in Mobile Station Classmark 2 IE

6

SS -> MS

AUTHENTICATION REQUEST

7

MS -> SS

AUTHENTICATION RESPONSE

8

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/2". The SS starts deciphering.

SS checks that there is no valid L3 message received using algorithm A5/2 (e.g. CIPHERING MODE COMPLETE) within 10s.

Specific Message Contents

None.

26.6.8.7 Ciphering mode with cipher key Kc128

26.6.8.7.1 Conformance requirements

1. When the MS receives the CIPHERING MODE COMMAND message with Ciphering Mode Setting information element set to "start ciphering", the MS starts ciphering and deciphering with the algorithm indicated by the "algorithm identifier" field:

– the MS responds with a CIPHERING MODE COMPLETE message in ciphered mode;

– the ciphering uses the cipher key determined during the authentication procedure.

2. The MS responds to the AUTHENTICATION REQUEST message with an AUTHENTICATION RESPONSE message and continues to use the ciphering key obtained from the previous authentication procedure.

3 The ASSIGNMENT COMMAND message may contain a cipher mode setting IE. In that case, this ciphering mode has to be applied on the new channel. If no such information is present, the ciphering mode is the same as on the previous channel. In either case the ciphering key shall not be changed as long as the key length remains unchanged.

References

3GPP TS 44.018 subclause 3.4.3, 3.4.7.

3GPP TS 24.008 subclause 4.3.2.

26.6.8.7.2 Test purpose

To verify that the MS calculates the correct Kc128 and starts ciphering using cipher algorithm A5/4 when it receives a CIPHERING MODE COMMAND message with Cipher Mode Setting = "Start Ciphering".

To verify that the correct Kc128 key is used after ASSIGNMENT COMMAND including cipher mode setting for A5/4 algorithm.

26.6.8.7.3 Method of test

Initial Conditions

System Simulator:

1 cell, default settings.

Mobile Station:

Test USIM is plugged into the MS. The MS is in the "idle, updated" state, with a TMSI allocated.

Specific PICS statements

PIXIT statements

Foreseen Final State of the MS

CC state U10-call active.

Test Procedure

The MS is made to originate a call. It shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a CM SERVICE REQUEST. The SS sends an AUTHENTICATION REQUEST with AUTN Information Element present and the MS shall answer with AUTHENTICATION RESPONSE with correct RES. Then the SS sends a CIPHERING MODE COMMAND ordering the MS to start ciphering with algorithm A5/4. After transmission of this command the SS starts deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in ciphered mode using the 128 bit cipher key calculated during the authentication procedure and continue to establish the call with a SETUP message.

The SS sends CALL PROCEEDING and initiates a new authentication procedure by sending AUTHENTICATION REQUEST with AUTN Information Element present and different RAND value. The MS shall respond with AUTHENTICATION RESPONSE with correct RES.

The call setup is proceeded with ALERTING. SS sends ASSIGNMENT COMMAND including cipher mode setting indicating A5/4. The MS shall respond with an ASSIGNMENT COMPLETE message in ciphered mode using the 128 bit cipher key calculated during the first authentication procedure. The call establishment is finished on the ciphered channel with CONNECT and CONNECT ACKNOWLEDGEMENT.

Maximum Duration of Test

1 minute.

Expected Sequence

Step

Direction

Message

Comments

1

MS -> SS

CHANNEL REQUEST

Establ. Cause = "Originating Call" NECI not set to 1

2

SS -> MS

IMMEDIATE ASSIGNMENT

3

MS -> SS

CM SERVICE REQUEST

4

SS -> MS

AUTHENTICATION REQUEST

5

MS -> SS

AUTHENTICATION RESPONSE

Cipher key Kc128 has been calculated.

"Auth. Response Parameter" IE shall be bit exact with the value as produced by the authentication algorithm (RES in this case)

"Auth. Response Parameter (extension)" IE might be included if the RES value is more than 4 octets long.

6

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/4". The SS starts deciphering.

7

MS -> SS

CIPHERING MODE COMPLETE

Sent in ciphered mode using the cipher key determined in step 5. The SS start enciphering.

8

MS -> SS

SETUP

9

SS -> MS

CALL PROCEEDING

10

SS -> MS

AUTHENTICATION REQUEST

11

MS -> SS

AUTHENTICATION RESPONSE

A new cipher key Kc128 has been calculated.

"Auth. Response Parameter" IE shall be bit exact with the value as produced by the authentication algorithm (RES in this case)

"Auth. Response Parameter (extension)" IE might be included if the RES value is more than 4 octets long.

12

SS -> MS

ALERTING

13

MS

Depending on the PIXIT, an alerting indication is given.

14

SS -> MS

ASSIGNMENT COMMAND

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/4"

15

MS -> SS

ASSIGNMENT COMPLETE

Sent in ciphered mode using the cipher key determined in step 5.

16

SS -> MS

CONNECT

17

MS -> SS

CONNECT ACKNOWLEDGE

Specific Message Contents

AUTHENTICATION REQUEST step 4

Information Element

value/remark

AUTN Information Element

present

– Length = 16

– Calculated as defined for Test USIM

CIPHERING MODE COMMAND step 6

Information Element

value/remark

Algorithm identifier

A5/4

AUTHENTICATION REQUEST step 10

Information Element

value/remark

RAND

different than in step 4

AUTN Information Element

present

– Length = 16

– Calculated as defined for Test USIM

ASSIGNMENT COMMAND step 14

Information Element

value/remark

Cipher Mode Setting

A5/4

26.6.8.8 Ciphering mode with cipher key Kc128 and algorithm changes

26.6.8.8.1 Conformance requirements

1. A ME supporting UMTS authentication challenge may support the following procedure: In order to avoid a synchronisation failure, if the same RAND is received twice, the mobile station shall store the received RAND together with the RES returned from the USIM in the volatile memory and compare it with any subsequently received RAND values, until the RAND value stored in the mobile station is deleted. If the stored RAND value is equal to the new received value in the AUTHENTICATION REQUEST message, then the mobile station shall not pass the RAND to the USIM, but shall immediately send the AUTHENTICATION RESPONSE message with the stored RES. If there is no valid stored RAND in the mobile station or the stored RAND is different from the new received value in the AUTHENTICATION REQUEST message, the mobile station shall pass the RAND to the USIM, shall override any previously stored RAND and RES with the new ones and start, or reset and restart timer T3218.

2 The ME with a USIM in use shall compute a new GSM Kc128 using the UMTS ciphering key and the UMTS integrity key from an established UMTS security context as specified in 3GPP TS 33.102 [5a]. The new GSM Kc128 shall be stored only in the ME.

3 The ASSIGNMENT COMMAND message may contain a cipher mode setting IE. In that case, this ciphering mode has to be applied on the new channel. If no such information is present, the ciphering mode is the same as on the previous channel. In either case the ciphering key shall not be changed as long as the key length remains unchanged. However, in case of a switch between ciphering algorithms requiring different key lengths, i.e. 64 or 128 bits, a change from the 64 bit key to the 128 bit key or vice versa must be performed

4 In a UMTS authentication challenge, the new UMTS ciphering key, the new GSM ciphering key and the new UMTS integrity key calculated from the challenge information shall overwrite the previous UMTS ciphering key, GSM ciphering key and UMTS integrity key. The new UMTS ciphering key, GSM ciphering key and UMTS integrity key are stored on the USIM together with the ciphering key sequence number. Furthermore, in A/Gb mode when after the authentication procedure an A5 ciphering algorithm that requires a 128-bit ciphering key is taken into use, then a new GSM Kc128 shall also be calculated as described in the subclause 4.3.2.3a.

References

3GPP TS 44.018 subclause 3.4.3

3GPP TS 24.008 subclause 4.3.2

26.6.8.8.2 Test purpose

To verify that the MS handles correctly key length changes when the SS orders the MS to change from A5/1 to A5/4 and vice versa.

26.6.8.8.3 Method of test

Initial Conditions

System Simulator:

1 cell, default settings.

Mobile Station:

Test USIM is plugged into the MS. The MS is in the "idle, updated" state, with a TMSI allocated.

Specific PICS statements

PIXIT statements

Foreseen Final State of the MS

"Idle, updated", with TMSI allocated.

Test Procedure

The MS is paged. The MS shall send at least one CHANNEL REQUEST message. The SS sends an IMMEDIATE ASSIGNMENT and the MS shall answer with a PAGING RESPONSE message .The SS sends an AUTHENTICATION REQUEST with AUTN Information Element present and the MS shall answer with AUTHENTICATION RESPONSE with correct RES. Then the SS sends a CIPHERING MODE COMMAND ordering the MS to start ciphering with algorithm A5/1. After transmission of this command the SS starts deciphering. The MS shall respond with a CIPHERING MODE COMPLETE message in ciphered mode using the 64 bit key Kc calculated during the authentication procedure.

The SS then sends another AUTHENTICATION REQUEST with AUTN Information Element present and the MS shall respond with AUTHENTICATION RESPONSE with correct RES The MS shall continue to use the old cipher key. Then the SS sends an ASSIGNMENT COMMAND with CIPHER MODE SETTING information element indicating to use algorithm A5/4. The MS shall respond with a ASSIGNMENT COMPLETE message in ciphered mode using the 128 bit cipher key Kc128 calculated during the previous authentication procedure.

After an identity procedure the SS then sends another AUTHENTICATION REQUEST with AUTN and the MS shall answer with an AUTHENTICATION RESPONSE with correct RES. Then the SS sends an ASSIGNMENT COMMAND with CIPHER MODE SETTING information element indicating to use algorithm A5/1. The MS completes the procedure by sending an ASSIGNMENT COMPLETE message in ciphered mode using the key calculated during the previous authentication.

After an identity procedure the SS sends a CHANNEL RELEASE to end the test.

Maximum Duration of Test

3 minutes.

Expected Sequence

Step

Direction

Message

Comments

1

SS -> MS

PAGING REQUEST TYPE 1

2

MS -> SS

CHANNEL REQUEST

3

SS -> MS

IMMEDIATE ASSIGNMENT

SS assigns a SDCCH8

4

MS -> SS

PAGING RESPONSE

5

SS -> MS

AUTHENTICATION REQUEST

6

MS -> SS

AUTHENTICATION RESPONSE

Cipher keys Kc and Kc128 have been calculated.

"Auth. Response Parameter" IE shall be bit exact with the value as produced by the authentication algorithm (RES in this case)

"Auth. Response Parameter (extension)" IE might be included if the RES value is more than 4 octets long.

7

SS -> MS

CIPHERING MODE COMMAND

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/1". The SS starts deciphering.

8

MS -> SS

CIPHERING MODE COMPLETE

Sent in ciphered mode using the cipher key Kc determined in step 6. The SS start enciphering.

9

SS -> MS

AUTHENTICATION REQUEST

10

MS -> SS

AUTHENTICATION RESPONSE

New cipher keys Kc and Kc128 have been calculated

Sent in ciphered mode using the cipher key Kc determined in step 6.

"Auth. Response Parameter" IE shall be bit exact with the value as produced by the authentication algorithm (RES in this case)

"Auth. Response Parameter (extension)" IE might be included if the RES value is more than 4 octets long.

11

SS -> MS

ASSIGNMENT COMMAND

SS assigns SDCCH4

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/4"

12

MS -> SS

ASSIGNMENT COMPLETE

Sent in ciphered mode using the cipher key Kc128 determined in step 6.

13

SS -> MS

IDENTITY REQUEST

14

MS -> SS

IDENTITY RESPONSE

15

SS -> MS

AUTHENTICATION REQUEST

16

MS -> SS

AUTHENTICATION RESPONSE

New cipher keys Kc and Kc128 have been calculated

Sent in ciphered mode using the cipher key Kc128 determined in step 6.

"Auth. Response Parameter" IE shall be bit exact with the value as produced by the authentication algorithm (RES in this case)

"Auth. Response Parameter (extension)" IE might be included if the RES value is more than 4 octets long.

17

SS -> MS

ASSIGNMENT COMMAND

SS assigns SDCCH8

Cipher Mode Setting = "Start Ciphering; cipher with algorithm A5/1"

18

MS -> SS

ASSIGNMENT COMPLETE

Sent in ciphered mode using cipher algorithm A5/1 and the cipher key Kc determined in step 6.

19

SS -> MS

IDENTITY REQUEST

20

MS -> SS

IDENTITY RESPONSE

21

SS -> MS

CHANNEL RELEASE

Specific Message Contents

AUTHENTICATION REQUEST step 5

Information Element

value/remark

RAND

Arbitrarily chosen

AUTN Information Element

present

– Length = 16

– Calculated as defined for Test USIM

CIPHERING MODE COMMAND step 7

Information Element

value/remark

Algorithm identifier

A5/1

AUTHENTICATION REQUEST step 9

Information Element

value/remark

RAND

different than in step 5

AUTN Information Element

present

– Length = 16

– Calculated as defined for Test USIM

ASSIGNMENT COMMAND step 11

Information Element

value/remark

Channel Description

– Channel Type

SDCCH4 (same type as old channel)

– TDMA offset

Chosen arbitrarily, but different to the one in use.

– Timeslot Number

Chosen arbitrarily, but different to the one in use.

Cipher Mode Setting

A5/4.

ASSIGNMENT COMMAND step 17

Information Element

value/remark

Channel Description

– Channel Type

SDCCH8

– TDMA offset

Chosen arbitrarily, but different to the one in use.

– Timeslot Number

Chosen arbitrarily, but different to the one in use.

– Training Sequence Code

5 (same as the BCC).

Cipher Mode Setting

A5/1

IDENTITY REQUEST step 17 and 19

Information Element

value/remark

Algorithm identifier

001 IMSI

AUTHENTICATION REQUEST step 15

Information Element

value/remark

RAND

different than in step 9

AUTN Information Element

present

– Length = 16

– Calculated as defined for Test USIM