GSM TIMER

(1)

Original Call (normal – No OACSU)

MS

BTS

BSC

MSC

Immediately Assignment Cmd.

Channel Activation Acknowledge ST9103 Channel Activation Channel Required Channel Request ET9103 ST3101 UI Immediately Assignment ST3126 ET3126

SABM [L3 Inf.] _{Establish Indication [L3 Inf.]}

ET3101

SCCP Connect Required [L3] ST9105

ET9105 SCCP Connect Confirm Unnumbered Acknowledge Authentication Request Authentication Request Authentication Request _ST3260 Authentication Response Authentication Response

ET3260 Authentication Response Identification Request Identification Request Identification Request ST3270 Identification Response Identification Response Identification Response ET3270 Ciphering Mode Cmd. Ciphering Mode Cmd. Ciphering Mode Cmd.

Ciphering Mode Complete

Ciphering Mode Complete Ciphering Mode Complete

TMSI Reallocation Cmd. TMSI Reallocation Cmd. TMSI Reallocation Cmd.

TMSI Reallocation Complete

ST3250

TMSI Reallocation Complete TMSI Reallocation Complete ET3250

Setup

Setup Setup

Call Proceed Call Proceed Call Proceed _{Assignment Request}

Physical Context Request Physical Context Confirm

ST9108 ET9108 Channel Activation TCH

ST9103 Channel Activation Acknowledge

ET9103 Assignment Command _ST3107 Assignment Command Release Request (SDCCH) SABM (FACCH) Establish Indication Unnumbered Acknowledge

Assignment Complete _{Assignment Complete}

ET3107 Assignment Complete RF Channel Release (SDCCH)

RF Channel Release Acknowledge

Alerting Alerting Alerting Connect Connect Connect Connect Acknowledge Connect Acknowledge Connect Acknowledge

(2)

Original Call (normal – OACSU)

MS

BTS

BSC

MSC

ET3101

ET3260 Authentication Response Identification Request Identification Request Identification Request _ST3270 Identification Response Identification Response Identification Response ET3270 Ciphering Mode Cmd. Ciphering Mode Cmd. Ciphering Mode Cmd.

ST3250

Setup

Setup Setup

Call Proceed Call Proceed Call Proceed

Assignment Request Physical Context Request

Physical Context Confirm

Alerting

Alerting Alerting

Connect Connect Connect

Connect Acknowledge

Connect Acknowledge Connect Acknowledge

(3)

Original Call (TCH Congestion)

MS

BTS

BSC

MSC

ET3101

ST3250

Setup

Setup Setup

* Physical Context Request * ST11

Release Complete ET11

Disconnect Frame Deactivate SACCH Release Indication Unnumbered Acknowledge Released RF Channel Release Clear Confirm Channel Release

Clear Request Clear Command Queuing Indication

(4)

Directed Retry

MS

BTS

BSC

MSC

ET3101

ST3250

Setup

Setup Setup

Queuing Indication Handover Access ST11 ET11 Channel Activation TCH ST9103 Channel Activation Acknowledge _ET9103 Handover Command _ST3103 Handover Command

Handover Detection SABM (FACCH) _{Establish Indication} Unnumbered Acknowledge

Handover Complete _{Handover Complete}

ET3103

Assignment Complete RF Channel Release (SDCCH)

Alerting

Alerting Alerting

Connect Connect Connect

Connect Acknowledge Connect Acknowledge Connect Acknowledge Physical Information ST3124 ET3124

At this time a handover alarm is raised and a target BTS is selected. T T S T T T T T S S T T T

(5)

Assignment Failure (T3107 expire)

MS

BTS

BSC

MSC

ET3101

ST3250

Setup

Setup Setup

ET9103 Assignment Command _ST3107 Assignment Command Assignment Failure Clear Command Released Released Complete ET3107 Clear Complete RF Channel Release

RF Channel Release Acknowledge ST9110 ET9110

(6)

Mobile Terminating Call

MS

BTS

BSC

MSC

SABM [Paging response] Establish Indication _{[Paging Response]}

ET3101 SCCP Connect Required [Paging Response] ST9105

ET3260 Authentication Response Identification Request Identification Request Identification Request _ST3270 Identification Response Identification Response Identification Response ET3270 Ciphering Mode Cmd. Ciphering Mode Cmd. Ciphering Mode Cmd.

ST3250

Setup

Setup Setup

Alerting Alerting Alerting Connect Connect Connect Connect Acknowledge Connect Acknowledge Connect Acknowledge Paging Paging Command Paging Request

(7)

Location Updating

MS

BTS

BSC

MSC

SABM [Location Update Request] Establish Indication

[Location Update request] _ET3101 SCCP Connect Required [Location Update Request] ST9105

ST3250

Deactivation SACCH Disconnect

Channel Release ST3210

ET3210 _{Clear Command}

Location Update Accept

Release Indication

Clear Confirm Unnumbered Acknowledge

Released RF Channel Release (SDCCH)

Released Complete Location Update Accept

Location Update Accept Channel Release

(8)

Internal Handover (Intra Cell)

MS

BTS

BSC

MSC

Internal Handover (Inter Cell Synchronous)



MS

BTS

Serving

BTS

Target

BSC

MSC

Measurement Report

Measurement Result Physical Context Request

OCh ST9108

OCh Physical Context Confirm ET9108 Channel Activation

NCh ST9103

NCh Channel Activation Acknowledge ET9103 Assignment Command ST3107 OCh Assignment Command OCh SABM NCh NCh Establish Indication Unnumbered Acknowledge NCh Assignment Complete NCh _{Assignment Complete} ET3107 Handover Performed RF Channel Release

ST_RCR_ACK ET_RCR_ACK

Measurement Report

Measurement Result Physical Context Request Physical Context Confirm

Channel Activation

ST9108 ET9108 ST9103 Channel Activation Acknowledge ET9103 Handover Command Handover Command ST3103 Handover Access Handover Access Handover Access Handover Access ST3106 Handover Detection SABM

ET3106 Establish Indication Unnumbered Acknowledge

Handover Complete

ET3103 Handover Performed RF Channel Release

ST_RCR_ACK ET_RCR_ACK ST200

(9)

Internal Handover (Inter Cell Asynchronous)



MS

BTS

Serving

BTS

Target

BSC

MSC

External Handover (Inter Cell Synchronous)



MS

BTS

Serving

BTS

Target

BSC

Serving

BSC

Target

MSC

Measurement Report

Measurement Result

Channel Activation

ST9103

Handover Access

Channel Activation Acknowledge

ST3105 Handover Command ST_RCR_ACK ST3214 ST3103 ET9103 Handover Command Handover Access Handover Access Handover Access SABM Physical Information Handover Detection ET200 ST200 ET3105 ET3214 Unnumbered Acknowledge Establish Indication

Physical Context Request

Handover Performed Handover Complete Handover Complete ET9108 ST9108 ET3103

RF Channel Release Acknowledge RF Channel Release Physical Context Confirm

ET_RCR_ACK Measurement Report Channel Activation SCCP Release Handover Required Handover Request Handover Command Measurement Result ST7 ET8 ST8 ET7 ST9103 Channel Activation Acknowledge

ET9103 HO Request ACK. Handover Command Handover Command SABM Physical Information Handover Access Handover Access Handover Access Handover Access ST200 ST3124 ST3106 ET3124 ET3106

Unnumbered Acknowledge Establish Indication SCCP Connect Required SCCP Connect Confirm ET200

RF Channel Release Clear Command

Handover Complete _{Handover Complete}

Handover Complete

RF Channel Release Acknowledge Clear Complete SCCP Release Complete

(10)

External Handover (Inter Cell  MSC Handover Failure)

MS

BTS

Serving

BTS

Target

BSC

Serving

BSC

Target

MSC

External Handover (Inter Cell  MS Handover Failure)

MS

BTS

Serving

BTS

Target

BSC

Serving

BSC

Target

MSC

Link Release (MS Release)

MS

BTS

BSC

MSC

Measurement Report _{Measurement Result}

Handover Required ST7

Handover Required Reject ET7 Measurement Report Measurement Report Measurement Report Measurement Result Measurement Result Measurement Result Handover Required ST HO_Req_Rej ET HO_Req_Rej Handover Command Handover Command Handover Command SABM Establish Indication UA Handover Failure Handover Failure Handover Failure ST8 ET8 Channel Release (DCCH) Channel Release ST3110 RF Channel Release Release Indication Disconnect (FACCH) Deactivation SACCH

ST9108 ET3111 Expire ET3110

ST3111

RF Channel Release ACK. Physical Context Confirm Physical Context Request Unnumbered Acknowledge ET_RCR_ACK ST_RCR_ACK ET9108 BSC Initiated Channel Release towards the MS ST3109 ET3109

(11)

Link Release (A Interface Release)

BSC

MSC

Clear Request ST9104 Clear Command Clear Complete SCCP Release SCCP Release Complete ET9104 ST9101 ET9101 BSC Initiated Normal

Call Release towards the MSC Clear Command Clear Complete SCCP Release SCCP Release Complete ST9101 ET9101 MSC Initiated Normal

Call Release towards the BSC

(12)

T200_D Position BTS T200_D for SDCCH SAPI 0

Start Sending I-Frame

Stop Receiving Acknowledgement

Value Default 220 ms Max. Min. Step

Action on expire Retransmission of I-Frame

T200_SD Position BTS T200_SD for SACCH/SDCCH SAPI 0

T200_ST Position BTS T200_ST for FACCH/HR SAPI 0

T200_TF Position BTS T200_TF for FACCH/FR SAPI 0

T200_D3 Position BTS T200_D3 for SDCCH SAPI 3

T200_S3 Position BTS T200_S3 for SACCH/TCH SAPI 3

T200 Position BSC Supervision of Acknowledge of L2 I-Frame

Start Sending of I-Frame

Stop Reception of RR, RNR, REJ or I-Frame

Action on expire Retransmission (number of retries given by N200 parameter)

T200 Position BTS Supervision of Acknowledge of L2 I-Frame

Start Sending of I-Frame

Stop Reception of RR, RNR, REJ or I-Frame

Value Default 260 ms Max. 335.2 ms Min. 83.8 ms Step 83.8 ms

Action on expire Retransmission (number of retries given by N200 parameter)

T203 Position BSC/BTS Link Supervision Timer

Start Reception of LAPD Frame

Stop Reception of LAPD Frame

Value Default 4 s Max. Min. Step

Action on expire Link Recover Proceed Start

T_Delay Position BSC Delay re-establishment LAPD link by BSC in order FU reset finish

Start LAPD Link Failure

Stop None

Action on expire Re-establish LAPD Link

(13)

Value Default 30 s Max. 300 s Min. 1 s Step

Action on expire Reset Counters

BCCH_CUT_Timer Position BTS Timeout for cut BCCH on loss LAPD connection

Start Loss LAPD connection

Stop Re-establish of LAPD connection

Action on expire Cut BCCH

T1_short Position BSC Supervision blocking/unblocking procedure

Start Sending of BLOCK or UNBLOCK

Stop Reception of BLOCK or UNBLOCK Acknowledge

Value Default 16 s Max. 25.5 s Min. 10 s Step 0.1 s

Action on expire The message send once more

T1_long Position BSC Hold off time before attempting another blocking/unblocking procedure

Start Second T1_short expire

Stop Reception of BLOCK or UNBLOCK Acknowledge

Value Default 60 s Max. 60 s Min. T1_short Step

Action on expire Sending BLOCK/UNBLOCK, start T1_short

T4 Position BSC Supervision of sending RESET to MSC

Start Sending RESET to MSC

Stop Reception of RESET ACK. or RESET from MSC

Value Default 3 s Max. 6553.5 s Min. 2 s Step 0.1 s

Action on expire The complete reset procedure repeated depending on parameter

T5 (T17) Position BSC Overload procedure

Start Reception of OVERLOAD from MSC or detection of a BSC overload

Stop None

Value Default 30 s Max. HFFFF Min. 0 Step

Action on expire New OVERLOAD msg. or internal overload-ind are not ignore any more

T6 (T18) Position BSC Overload procedure

Start Reception of OVERLOAD from MSC or detection of a BSC overload

Stop None

Action on expire Traffic increased to next level

T7 Position BSC During BSC will not re-present cells that were rejected by MSC

Start A handover alarm was detected and the HND_REQ was sent to MSC

Stop Reception HND_CMD or HND_REQ_REJ from MSC

Value Default 5 s Max. 20 s Min. 0 Step 0.1 s

Action on expire The BSC may report target cell, previously reported, again in an external HO

T8 Position BSC Handover supervision in the (serving) BSC

Start Sending of HND_CMD to MS or reception of REL_REQ from BTS

Stop Reception of CLR_CMD from MSC or reception of HND_FAILURE from MS

Value Default 14 s Max. 25.5 s Min. 0 Step 0.1 s

Action on expire CLR_REQ sent to MSC, CHN_REL sent to MS, RF_CHN_REL sent to BTS

T11 Position BSC Only use to TCH connection

Start An ASSIGNMENT_REQ is stored in a queue

Stop The queued ASSIGNMENT_REQ is served or deleted because of a new higher priority REQ

Value Default 15 s Max. 255 s Min. 0 Step 1 s

(14)

T13 Position BSC Reset guard period

Start Reception of RESET from MSC

Stop SSP/SPI received from SCCP or another RESET from MSC

Action on expire Send RESET ACK. to MSC

T3101 Position BSC/BTS Supervision of Immediately Assignment Procedure

Start Sending IMMDIATELY_ASSIGN_CMD to the BTS

Stop Reception of ESTABLSH INDICATION from BTS

Action on expire RF CHANNEL RELEASE send to BTS

T3103 Position BSC/MSC Supervision of internal intracell HO and internal DR Procedure

Start Sending of HO_CMD to MS (via BTS)

Stop Reception of HO_CMPL from MS on new Channel or HO_FAILURE on old channel

Value Default 16.5 s Max. 25.5 s Min. 0 Step 0.1 s

Action on expire The old channel released by sending CLR_REQ to MSC

T3105_D Position BTS Reception of PHY_INF. in the asyncr. HO performed on SDCCH

Start Sending PHYSICAL INFORMATION to MS on SDCCH

Stop Reception of SABM from MS on SDCCH or a correct L2 signalling (SDCCH/SACCH)

Value Default 220 ms Max. 220 ms Min. 200 ms Step

Action on expire BTS send CONN_FAIL indication, BSC send HO_FAIL

T3105_F Position BTS Repetition PHY_INF. in the asyncr. HO performed on FACCH

Start Sending of PHYSICAL INFORMATION to MS on FACCH

Stop Reception of SABM from MS on FACCH or a correct L2 signalling or correct TCH frame

T3106_D Position BTS Supervision of reception SABM from MS on SDCCH

Start Reception of HO_ACCESS from MS on SDCCH

Stop Reception of SABM from MS on SDCCH or a correct L2 signalling (SDCCH/SACCH)

T3106_F Position BTS Supervision of reception SABM from MS on FACCH

Start Reception of HO_ACCESS from MS on FACCH

Stop Reception of SABM from MS on FACCH or a correct L2 signalling or correct TCH frame

T3107 (T10) Position BSC Supervision of Assignment Procedure and internal intracell HO

Start Sending of ASSIGNMENT COMMAND to MS via BTS

Stop Reception of ASSIGN_COMP or ASSIGN_FAIL from MS or reestablishment of MS to old _{channel (Not Phase 1)}

Value Default 14 s Max. 25.5 s Min. 0 Step

Action on expire The old and new channel released. All connection to the MS are cleared

T3109 Position BSC/BTS Supervision of channel release procedure

Start Sending of CHANNEL RELEASE to MS via BTS

Stop Reception of REL_IND from BTS after BTS received DISC-frame from MS

(15)

T3111 Position BSC Delay of channel release on air interface

Start Reception of REL_IND from BTS after BTS received DISC-frame from MS

Stop None

Value Default 0.5 s Max. 25.5 s Min. 0 Step 0.1 s

Action on expire Send RF CHANNEL RELEASE to BTS

T9101 Position BSC Supervision of call clearing procedure on A interface (SCCP_REL)

Start Sending of CLEAR COMPLETE to MSC

Stop Reception of SCCP RELEASED from MSC

Action on expire Send SCCP RELEASE to MSC

T9103 Position BSC Supervision of channel activation procedure

Start Sending of CHANNEL ACTIVATION to BTS

Stop Reception of CHN_ACT_ACK or CHN_ACT_NACK from BTS

Action on expire NOTE 1

T9103 Position BSC Supervision of Mode Modify procedure

Start Sending of MODE MODIFY to BTS

Stop Reception of MODE MODIFY ACK. from BTS

Action on expire NOTE 2

T9104 Position BSC Supervision of clear request from BSC

Start Sending of CLEAR REQUEST to MSC

Stop Reception of CLEAR COMMAND from MSC

Value Default 2 s Max. 25.5 s Min. 0 Step

Action on expire Repeat CLEAR REQUEST

T9105 Position BSC Supervision of SCCP connection procedure

Start Sending of SCCP CONNECTION REQUEST to MSC

Stop Reception of SCCP CONNECTION COMFIRM or SCCP_CON_REF

Action on expire Send CHANNEL RELEASE to MS via BTS

T9108 Position BSC Supervision of Physical Context Request procedure

Start Sending PHYSICAL CONTEXT REQUEST to BTS

Stop Reception of PHYSICSL CONTEXT CONFIRM from BTS

Action on expire Procedure continues using default value

T9110 Position BSC Supervision of MSC response HO_FAIL and ASSIGN_FAIL

Start Sending of HO_FAIL or ASSIGN_FAIL to MSC

Stop Reception of CLEAR_CMD from MSC or new HO_REQ on same SCCP connect

Action on expire Clear initiated towards MSC, if due to ASSIGN_FAIL for MS then reset circuit start

T_9112 Position BSC Supervision of channel modification in MS

Start Sending of CHANNEL MODE MODIFY to MS

Stop Reception of CHANNEL MODE MODIFY ACKNOWLEDGE

Action on expire Sending ASSIGNMENT FAILURE to MSC

T9113 Position BSC Supervision of external HO procedure in the target BSC

Start Sending HO_REQ_ACK to MSC after having received HO_REQ from MSC

Stop Reception of HO COMPLETE from MS via BTS or CLEAR COMMAND from MSC

(16)

MS_P_CON_ACK Position BSC(Mode A)/BTS(Mode B) Supervision of MS PC procedure

Start Sending MS_PWR_CMD to MS with a new MS_TXPWR value

Stop Received right MS_TXPWR_CONF value in L1header from MS or call released or MS lost

Value Default 2.88 s _{(3 960ms)}_ Max. 29.76 s _{(31 960ms)}_ Min. 0 Step

Action on expire PC procedure start immediately without waiting for MS_P_CON_INT timer expire

BS_P_CON_ACK Position BSC Supervision of BS power control procedure

Start Sending BS_PWR_CMD to BTS with a new BS_TXPWR value

Stop Received right BS_TXPWR_CONF value in L1 header from BTS or call released or MS lost

Value Default 2.88 (3 960ms)_s  Max. 29.76 (31 960ms) _s  Min. 0 Step

Action on expire PC procedure start immediately without waiting for BS_P_CON_INT timer expire

MS_P_CON_INT Position Note 3 Delay next PC procedure after previous procedure finish

Start Stop previous PC comparison procedure

Stop The call released or MS lost

Action on expire The next PC comparison procedure start

BS_P_CON_INT Position Note 3 Delay next PC procedure after previous procedure finish

Start Stop previous PC comparison procedure

Action on expire The next PC comparison procedure start

THOmin Position BTS (Mode A) Delay consecutive HO alarm inside BTS (Mode A)

Start Stop previous HO threshold comparison procedure in BTS

Value Default 4.8 s (5 960ms) Max. 29.76 s _{(31 960ms)}_ Min. 0 Step

Action on expire The next HO threshold comparison start and next HO alarm allowed

T_qho Position BSC Time allowed to queue a HO_REQ message

Start A HANDOVER REQUEST message store in queue

Stop The request is served or deleted because of new higher priority request

Value Default 5 s Max. 255 s Min. 0 Step 1 s

Action on expire Remove request from queue and send HO_FAIL to MSC

T_i Position BSC Delay the reaction on reception of SPI/SSP

Start SSP/SPI received from SCCP

Stop SSP/SPI received from SCCP

Value Default 0 Max. 3 s Min. 0 Step

Action on expire The RESET procedure start

T_RCR_ACK Position BSC Supervision RF CHANNEL RELEASE procedure

Start Sending RF CHANNEL RELEASE to BTS

Stop Received RF CHANNEL RELEASE ACK. from BTS

Action on expire 1st expire: RF_CHN_REL repeat; 2nd expire: RF_CHN_REL abandoned

T_BTS_EST_CNF Position BSC Supervision SAPI 3 EST_REQ/EST_CONF procedure

Start EST_REQ for SAPI 3 is sent to BTS

Stop EST_CNF for SAPI 3 received from BTS

Action on expire SAPI"N"_REJ send to MSC and REL_REQUEST send to BTS

T_BTS_RLS_CNF Position BSC Supervision SAPI 3 REL_REQ/REL_CONF procedure

Start REL_REQ for SAPI 3 is sent to BTS

(17)

(18)

T_HO_REQD_LOST Position BSC Guard period for sending HO_REQD to MSC

Start A HO alarm was detected and HO_REQD sent to MSC

Stop Received HO_CMD or HO_REQD_REJ from MSC

Action on expire An O&M alarm is sent

T_1 Position BSC Overload procedure

Start Starting of access class barring in BSC

Stop None

Value Default 30 s Max. HFFFF Min. 30 s Step

Action on expire The next access classes can be barred

T_2 Position BSC Overload procedure

Start Starting of access class barring in BSC

Stop None

Value Default 50 s Max. HFFFF Min. 30 s Step

Action on expire The next access classes are barred

T_SUP Position BTS (FUCO) Overload detection in FU

Start Detection of a FU-internal Overload_Indication (Counter C in FU is incremented)

Stop None

Value Default 1 s Max. 25.5 s Min. 0.1 s Step 0.1 s

Action on expire The counter in FU is decrement

T_LB_OV Position BSC Leaky bucket timer for overload procedure

Start Reception of an OVERLOAD from a non BCCH-FU

Stop None

Value Default 10 s Max. 25.5 s Min. 0.1 s Step

Action on expire The leaky bucket counter in BSC is decrement

TS_TCUA Position BSC Inhibition of successive load reduction in TCU

Start The load of TCU is reduced by one step

Stop None

Value Default 10 s Max. 50 s Min. 0 Step

Action on expire The TCU load can be reduced to next step

TL_TCUA Position BSC Load increased in TCU

Start The load of TCU is increased by one step

Stop None

Action on expire The TCU load is increased to next step

T_COUNT_I Position BSC Leaky bucket timer for TCU overload

Start A TCU overload is detected in BSC (the counter COUNT_I is incremented)

Stop None

Action on expire The counter COUNT_I is decrement

T_OVL_MSC Position BSC Guard time for sending of OVERLOAD message to MSC

Start Sending OVERLOAD to MSC

Stop None

Value Default 20 s Max. 6553.5 s Min. 0.1 s Step 0.1 s

Action on expire Sending of OVEROAD to MSC is allowed

T12 (T19) Position BSC Supervision of RESET CIRCUIT procedure

Start Sending RESET CIRCUIT to MSC

Stop Reception RESET CIRCUIT ACK. from MSC

Value Default 10 s Max. 25.5 s Min. 0.1 s Step

(19)

T_CFI_TR Position BTS (FUCO) Guard time for filtering of transcoder alarms

Start Sending of ESTABLISH INDICATION to BSC

Stop None

Action on expire Sending of CONN_FAIL_IND with cause Remote Transcoder Failure become possible

T_SYNC Position TRAU/BTS Detection of loss of sync. between BTS and transcoder for FR CHN

Start Loss of frame sync.

Stop See TRCU/BTS interface spec.

Value Default 1/1 s Max. 1/63 s Min. 1/1 s Step

Action on expire See TRCU/BTS interface spec.

T_SYNCd Position TRAU/BTS Detection of loss sync. on DL from transcoder

Start Loss of frame sync. to BTS for HR and EFRCHN

Stop Frame sync. is again obtained

Action on expire BTS sent CONN_FAIL_IND with cause "Remote Transcoder Failure"

T_STNCu Position TRAU/BTS Detection of UL frame error for HR and EFR channel

Start A TRAU frame indicating an UL Frame Error which no error on sync. pattern and control bits _received Stop 3 consecutive TRAU frames received without UL Frame Error, without errors on frame sync. _{pattern and control bits}

Action on expire BTS sent CONN_FAIL_IND with cause "Remote Transcoder Failure"

T_release Position TRAU Supervision of call release procedure and loss of sync. in TRAU(HR and

Start Loss of frame sync. EFR Channel)

Stop Frame sync. is again obtained

Action on expire TRAU terminates the operation (goes idle) until a valid frame received again

T_ta Position BTS Control frequency of updating the time alignment changes made for HR CHN

Start TA compound request has been sent to TRAU by BTS

Stop None

Value Default 120 ms (240 ms) Max. 1000 ms Min. 60 ms (160 ms) Step 20 ms

Action on expire If needed the BTS can send a new TA compound request to TRAU

T_FILTER Position BSC Filter of HO alarm

Start Detection of HO alarm

Stop None

Action on expire Enable a new HO alarm detection

T_ALG_CONF Position BTS Supervision of Power Control and HO algorithm configuration

Start Reception of Pre-process Configuration in BTS

Stop Reception of BS_POWER_CONTROL and MS_POWER_CONTROL in BTS

Value Default Max. 30 s Min. 5 s Step

Action on expire O&M alarm generate

T_INTRF_L3 Position BTS Repetition time for sending RF RESOURCE INDICATION

Start RF RESOURCE INDICATION transmitted to BSC

Stop None

(20)

TRACING_PERIOD Position BTS In mode A RPOPREC_MEAS_RES to BSC

Start PROPREC_MEAS_RES transmitted to BSC

Stop None

Value Default 63 SDCCH mf Max. 63 SDCCH mf Min. 0 Step

Action on expire A new PREPROC_MEAS_RES can be sent to BSC and timer restart

T_RECOVERY Position BSC Control of trace file transmission to OMC_R/LT on interface failure

Start Failure on BSS-OMC_R/LT interface or disk full and failure presumed exist on

Stop None BSS-OMC_R/LT interface

Value Default 10 mn Max. 10 mn Min. 10 mn Step

Action on expire Note 4

T_MS_CELL_REJ Position BSC Guard timer during MS failed HO to cells won't be used subsequent

Start HO_FAILURE received from MS (and N_PREF_CELLS=1)

Stop Reception of CLR_CMD, RESET, RESET_CIRCUIT, CONN_FAIL_IND, SCCP_N_DISC, _{ASSIGN_REQ}

Action on expire The cell which MS failed HO to may again be used in HO attempts

T_SDDCH_MEAS_REP Position BSC Clear SDCCH CHN which remain connected forever

Start Whenever a SDCCH CHN is allocation in a cell either during an IMME_ASSIGN or channel

Stop None change such as inter-cell HO into current cell

T(conn_est) Position BSC SCCP timer waiting for CONN_CONF

Start Sending CONNECTION REQUEST to MSC

Stop Reception CONN_CONF, CONN_REFUSED, ROUTING_FAIL from MSC

Action on expire N-DISCONNECT INDICATION is sent to SCCP user

T(ias) Position BSC Delay to send a message on a connection section

Start Reception CONN_CONF from MSC, any message send on connection section(restart timer)

Stop Sending of RELEASED to MSC, reception of RELEASED from MSC

Value Default 450 s Max. Min. Step 6 s

Action on expire An Inactivity Test (IT) is sent on connection section

T(iar) Position BSC Waiting to receive a message on a connection section

Start Reception CONN_CONF from MSC, any message send on connection section(restart timer)

Stop Sending of RELEASED to MSC, reception of RELEASED from MSC

Value Default 1002 s Max. Min. Step 6 s

T(rel) Position BSC Waiting for RELEASE COMPLETE

Start Sending RELEASED to MSC

Stop Reception RELEASE COMPLETE from MSC

Value Default 15 s Max. 15 s Min. 4 s Step 0.5 s

Action on expire RELEASE message is sent to MSC and T(rel) is start again

T(stat inf.) Position BSC Delay between requests for sub-system status information

Start Sending SST message to MSC

Stop Reception SSA message from MSC

Value Default 30 s Max. 1200 s Min. 6 s Step 0.5 s

(21)

T303 Position MS

Start CM SERVICE REQUEST sent

Stop CALL_PROC or REL_COMP received

Action on expire 1st expire clear the call; 2nd expire the timer is not restarted

Start DISCONNECT sent

Stop RELEASE or DISCONNECT received

Action on expire 1st expire RELEASE sent; 2nd expire timer is not restarted

Start RELEASE sent

Stop RELEASE_COMPLETE or RELEASE received

Action on expire 1st expire retransmission RELEASE, restart 308; 2nd expire call ref. release

Start CALL_PROC received

Stop Alert, CONN, DISC or PROG received

Action on expire 1st expire send DISCONNECT; 2nd expire timer is not restart

Start CONNECT sent

Stop CONNECT_ACKNOWLEDGE received

Action on expire 1st expire send DISC; 2nd expire timer is not restart

Start MODIFY sent

Stop MODIFY_COMPLETE or MODIFY_REJECT received

Action on expire 1st expire clear the call; 2nd expire timer is not restart

Start LOCATION UPDATE REQUEST sent

Stop LOC_UPD_ACC, LOC_UPD_REJ, AUTH_REJ, Lower layer failure

Action on expire Start T3211

Start LOC_UPD_REJ with cause 17 network failure, Lower layer failure or RR connection released

Stop Time out, request MM_CONN_EST, change LA after RR connection abort

Value Default 15 s Max. Min. Step during LOC_UPDATING

Action on expire Restart the Location Update Procedure

Start Location Updating Failure

Stop Change of BCCH parameter

Action on expire New random attempt

Start IMSI Detach

Stop Release from RX-sublayer

(22)

Start CM_SERVICE_REQ, CM_RESET_REQ

Stop Ciphering Mode setting, CM_SERVICE_ACC, CM_SERVICE_REJ

Action on expire Provide Release Indication

Start Note 7

Stop Note 8

Action on expire Abort the RR connection

T3250 Position BSC

Start TMSI_REAL_CMD or LOC_UPD_ACC with new TMSI sent

Stop TMSI_REAL_COMP receive

Action on expire Optionally release RR connection

Start LOC_UPD_ACC sent with follow on proceed

Stop CM SERVICE REQEST

Value Default Max. Min. Step

Action on expire Release RR connection or use for MS terminating call

Start AUTHENTICATION REQUEST sent

Stop AUTHENTICATION RESPONSE received

Action on expire Optional release RR connection

Start IDENTITY REQUEST sent

Stop IDENTITY RESPONSE received

Action on expire Optional release RR connection

T3122 Position MS This timer is used during Random Access

Start Receipt of IMMEDIATELY ASSIGNMENT REJECT

Stop None

Value Given by network in IMMEDIATELY ASSIGNENT REJECT message

Action on expire

T3124 Position MS Used in the seizure procedure during HO when two cell not synchronised Start

Stop

Value If channel type of channel allocated in HO_CMD is SDCCH(+SACCH) it is 675 ms;

Action on expire otherwise it is320 ms.

Start Note 9

Stop Receipt IMMEDIATE ASSIGNMENT or IMMEDIATE ASSIGNMENT EXTENDED

Value Default Max. 5 s Min. T+2S slots of the MS's RACH Step

Action on expire Immediately Assignment Procedure is aborted

Start After MS has the UL investigation procedure and the UL is busy

Stop Receipt of the first UPLINK FREE message

(23)

Start After sending the first CHN_REQ message during a VGCS uplink access procedure

Stop Receipt of a VGCS ACCESS GRANT message

(24)

Note 1: Channel Activation Procedure

Immediate assignment: Abandon procedure

Assignment: Assignment Failure to MSC

Intra-cell HO: Force inter-cell HO depending on EN_INTRA_CELL_REPEATED

Inter-cell HO: Try a new int. HO if possible

External HO: HO Failure to MSC

In all cases the BSC attempts to release the resource in the BTS

Note 2: Mode Modify Procedure

Sending of ASSIGNMENT FAILURE to MSC

Note 3: Position is in BSC (Mode B) or in BTS (Mode A)

Note 4: BSC checks disk to see if any trace files are in Recovery Needed condition and should be

reported to OMC_R/LT. If interface is OK files are sent, if not the timer is restarted.

Note 5: If no MEASUREMENT RESULT message has been received during the timer period, the

SDCCH channel is released locally within the BSC and if a SCCP connection exists, a release scenario

is done towards the MSC.

Note 6: 1> The connection release procedure is initiated on a temporary connection section.

2> An O&M function is alerted for a permanent connection section.

Note 7: The MS receives a LOCATION UPDATING ACCEPT;

The MS receives a LOCATION UPDATING REJECT;

The MS sends a CM SERVICE ABORT;

The MS has released or aborted all MM connection.

Note 8: Receipt of a MM message;

Receipt of a CM message that initiates establishment of a CM connection.

Note 9: This timer is started either after sending the maximum allowed number of CHANNEL

REQUEST message during an immediate assignment procedure or on receipt an IMMEDIATE

ASSINGMENT REJECT message.

(25)

In Release 5 there are some changes in procedure.

LOCATION UPDATING (for phase 1 extended and phase 2/2+ MS)

MS

BTS

BSC

MSC

LOCATION UPDATING (for phase 1 MS)

MS

BTS

BSC

MSC

MSC initiated Classmark enquiry (phase 1 MS)

MS

BTS

BSC

MSC

MSC initiated Classmark enquiry (phase 1 extended and phase 2/2+ MS)

MS

BTS

BSC

MSC

Connect Confirm DATA REQUEST (CM ENQ)

CM ENQ

CM UPDATE DATA IND (CM CHG)

CM CHANGE

Connect Required Unnumbered Acknowledge SACCH Inf. Modify

CM ENQ

CM UPDATE DATA IND (CM CHG)

CM CHANGE

CM ENQ

DATA IND (RR Status) RR Status

CM Request

CM ENQ

CM UPDATE DATA IND (RR Status)

RR Status

(26)

Location Updating with follow on call (phase 2/2+ MS only)

MS

BTS

BSC

MSC

Early sending of CLASSMARK CHANGE (phase 2/2+ MS)

MS

BTS

BSC

MSC

Connect Confirm LOC_UPD_ACC LOC_UPD_ACC CM UPDATE DATA IND CM_SERV_REQ (MS CM2) CM_SERVICE_REQUEST LOC_UPD_ACC CM_SERV_REQ (MS CM 2) Channel Request Immediately Assignment Channel Activation Acknowledge

Channel Activation Channel Request Establish Indication SABM Immediately Assignment Connect Required SACCH Inf. Modify

Unnumbered Acknowledge

CM UPDATE Connect Confirm DATA Indication (CM CHG)