WWW.HUAWEI.COM HUAWEI TECHNOLOGIES CO., LTD. GSM Signaling Procedure Huawei Vietnam RF Team
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Layer 3 Introduction► RR :( Radio Resource Management)
Control by MS、 BTS and BSC Function Sample
– Paging Management– Ciphered Mode Management– Frequency Redefinition– Dedicated Channel Assignment– Handover Management – Measures and Power Control
► MM :( Mobility Management) Control by MS and MSC / VLR Function Sample
– Authentication / Identification Procedures– Location Updating– IMSI Attach / Detach
GSM Network Protocol
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► CC : ( Call Control) Control by MS and MSC Function Sample
– Call processing and routing– Short Message Service– Supplementary Service
GSM Network Protocol
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GSM Frame Structure
0 1 2 3 4 5 6 2042 2043 2044 2045 2046 2047
0 1 2 30 1
1 (26-frame) multiframe = 26 TDMA frames (120 ms)
(= 51 (26-frame) multiframes or 26 (51-frame) multiframes)
47 48 49 5024 25
1 (51-frame) multiframe = 51 TDMA frames (3060/13 ms)
0 1 2 3 46 47 48 49 500 1 2 3 4 22 23 24 25
0 1 2 3 4 5 6 7
1 T D M A fram e = 8 tim e slots (120/26 or 4,615 m s)
1 tim e slot = 156,25 bit durations (15/26 o r 0,577 m s)(1 bit duration = 48/13 or 3,69 µ s)
TB Encrypted bits Training sequence Encrypted bits TB GP8,2535826583
Fixed bits TB GP8.253
TB Encrypted bits Encrypted bits TB GP8,2539643
TB Encrypted bits TB GP68,25336418
339
142
Normal burst (NB)
Frequency correction burst (FB)
Access burst (AB)
(TB: Tail bits - GP: Guard period)
1 superfram e = 1 326 T D M A fram e s (6,12 s)
Synchronization sequence
Synchronization sequence
Synchronization burst (SB)
1 hyperfram e = 2 048 superfram es = 2 715 648 T D M A fram es (3 h 28 m n 53 s 760 m s)
3TB
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GSM Multi-Frame Channel
F S CC -
D 0D 0
D 1D 1
D 2D 2
D 3D 3
D 4D 4
D 5D 5
D 6D 6
D 7D 7
A 0A 4
D 0D 0
D 1D 1
D 2D 2
D 3D 3
D 4D 4
D 5D 5
D 6D 6
D 7D 7
A 0A 4
A 3A 1A 5
A 2A 6 A 7 --
- - --
--- - -
-A 3A 1A 5
A 2A 6 A 7
--
RD 3D 3
D 0D 0
D 1D 1
D 2D 2
A 0 A 1A 3A 2
F SF SD 3D 2
D 3D 2F SF S
D 1D 0D 1D 0
A 2 A 3A 1A 0
S:C:A:
F:B:D:R:
TDMA frame for frequency correction burstTDMA frame for BCCHTDMA frame for SDCCHTDMA frame for RACH
BCCH + CCCH(downlink)
BCCH + CCCH(uplink)
8 SDCCH/8(uplink)
8 SDCCH/8(downlink)
BCCH + CCCH4 SDCCH/4(downlink)
BCCH + CCCH4 SDCCH/4
(uplink)
TDMA frame for synchronization burstTDMA frame for CCCHTDMA frame for SACCH/C
51 fram es 235.38 m s»
R R R R R R R R R R R R R R R R R R R R R RR R R R R R R R R R R R R R R R R R R R R R R
RR RRR
R RR
F S B CF B CS
F S CCF S CC
F S CCCCF SCCF SF S B C
R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R RR R R R R
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GSM Multi-Frame Channel
T T T T T T T T T T T T A T T T T T T T T T T T T -
T t T t T t T t T t T t A T t T t T t T t T t T a
(a)
(b)
26 frames = 120 ms
(a) case of one full rate TCHT, t: TDMA frame for TCH A, a: TDMA frame for SACCH/T-: idle TDMA frame
(b) case of two half rate TCHs
t
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Content► Establish Signaling Link, used for signaling transm
issionWhen MS want to connect to network, firstly must establish the radio signaling link and A-interface link
► Step includedPaging ProcedureRandom Access ProcedureImmediate Assignment ProcedureSCCP Connection Establishment Procedure
Singling Link Establish Procedure
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MS BTS BSC MSCChannel Request
Channel Required
Channel Activation( SD)
Channel Act Ack ( SD)
Immediate AssignmentCommand
UI Imm Assignment / Imm Ass Ext
ST9103
ET9103
ST3126
ET3126
ST3101
SABM [L3 Info] Est Ind [L3 Info]SCCP Con Rqrd [L3]
SCCP Conn Confirm
ET3101
ST9105
ET9105
UA [L3 Info]
( RACH)( Est Cause, Rnd Nbr)( Est Cause, Rnd Nbr, FN, TA)
RACH_TA_Filtering
( TA, BS/MS_TxPwr -->Max, Chann)
Timer;S --
Start;E -- End
Entity
Um Abis A
( Rnd Nbr, TDMA Frame Nbr, Chan , TA)( AGCH)
For 2 MS at same time
( SDCCH)
CM Serv Req, Pag Res, Loc Update Req
Set Asynchronous Balance
Unnumbered Ack
Singling Link Establish Procedure
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MS BTS BSC MSCAuthentication Req
Ciphering Mode Cmd
Authentication ReqAuthentication ReqAuthentication Resp Authentication Resp
Authentication Resp
Encryption CommandCiphering Mode CmdCiphering Mode Cmp Ciphering Mode CmpCiphering Mode Cmp
TMSI Realloc CmdTMSI Realloc Cmd TMSI Realloc Cmd
TMSI Realloc Cmp TMSI Realloc Cmp TMSI Realloc Cmp
Authenti
cation
Cipherin
gTMSI R
ealloc
ST3260
ET3260*Authentication Reject*
Identifi
cation Identification Request
ST3270
ET3270
Identification Request Identification RequestIdentification Response
Identification RespIdentification Response
ST3250
ET3250
( RAND)
( SRES)
RAND and Ki by A3 algorithm get SRES; by A8 algorithm get Kc
Check
SRES
( IMSI)
( Permitted Alg, Kc)( Alg, Kc)( Alg( A5))
( TMSI)
VLR get from HLR the RAND/SRES/Kc
Authentication, Identification, Ciphering, TMSI Re-allocation
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Content► Normal Assignment for TCH► Special case
QueuingDirected Retry
TCH Assignment Procedure
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MS BTS BSC MSC
Channel Activation TCH
SABM (FACCH)
Channel Activation Ack.
Assignment CommandAssignment Command
Assignment RequestPhysical Context Request
Physical Context Confirm
Establish IndicationUA
Assignment Complete Assignment CompleteAssignment Cmp
RF Channel Release (SD)
RF Channel Release Ack.
STrr1
ETrr1
ST9108
ET9108
ST9103
ET9103
ST3107
ET3107
( Chn Type, Priority, CIC, DL DTX, Queuing Flag)( TA, MS/BS_TxPwr)
( SDCCH)
( TA, MS/BS_TxPwr)
( MA, TS, HSN, MAIO,MS_TxPwr)
On TCH if need signaling, then use Stealing Flag transfer TCH
into FACCH
TCH Assignment Procedure
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Frequency Encoding
► Frequency Encoding Fixed Bitmap —— Bitmap 0 —— Use for 1~124 AFRCN
TCH Assignment Procedure---Abis interface
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MS BTS BSC MSC
SABM (FACCH)
Channel Activation
HO CMD
Assignment Request
Physical Con Req
Chan. Act. Ack.
HO Detection
UA
Phys. Info
Assignment Cmp
ST11
ST3103
Queuing Indication
ET11At this time, a TCH become free
TCH Queue
Assignment RequestST11 Queuing Indication
ET11 A Handover alarm is raised. A target BTS is selected
HO CMDHO Access
ST9103ET9103
T
T
ST
T
Establish IndicationTT
HO CMP T HO CMP
ST3124
ET3124
ET3103
Direct Retry
TCH Assignment Procedure---Queue and Direct Retry
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MOC( Early Assignment)
MS BTS BSC MSC
Call Proceeding
ESTIN (CM_Serv_Req)RR Connection Establishment RR Connection Establishment RR Connection Establishment
Authentication Procedure Authentication Procedure Authentication ProcedureCiphering Procedure Ciphering ProcedureCiphering Procedure
TMSI Realloc Procedure TMSI Realloc Procedure TMSI Realloc Procedure
SETUP SETUPSETUP
Call Proceeding Call Proceeding
Assignment Procedure Assignment Procedure Assignment ProcedureAlertingAlertingAlerting
ConnectConnectConnect
Connect Ack. Connect Ack. Connect Ack.
Speech
CM_Serv_Req
( called party nbr)
Establish TCH first, then connect another part. Alerting transfer on
TCH
( CM Serv Type, Mobile ID, Classmark2, Priority,)
SDCCH
TCH
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MOC —— A interface
A interface
Two times Classmark Update, the 1st one is caused by Early Classmark Sending (ECSC); 2nd caused by BSC send Classmark Enquiry
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CM Service Request
MOC est/pkt mode con estabShort message serviceSuppl service activation
CLASSMARK
MOC —— A interface
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CLASSMARK► Include
MS Revision Level MS Ciphering Capability MS Frequency Capability MS RF Power Capability in Each Band
MOC —— A interface
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MS BTS BSC MSC
Call Proceeding
ESTIN (CM_Serv_Req)RR Connection Establishment RR Connection Establishment RR Connection Establishment
Authentication Procedure Authentication Procedure Authentication ProcedureCiphering Procedure Ciphering ProcedureCiphering Procedure
TMSI Realloc Procedure TMSI Realloc Procedure TMSI Realloc Procedure
SETUP SETUPSETUP
Call Proceeding Call Proceeding
Assignment Procedure Assignment Procedure Assignment Procedure
AlertingAlertingAlerting
ConnectConnectConnect
Connect Ack. Connect Ack. Connect Ack.
Speech
CM_Serv_Req
SDCCH
TCH
Establish another side channel, then setup TCH , Alerting send on S
DCCH
MOC( Late Assignment)
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MS BTS BSC MSC
Call Confirmed
ESTIN (Paging Resp)RR Connection Establishment RR Connection Establishment RR Connection Establishment
Authentication Procedure Authentication Procedure Authentication ProcedureCiphering Procedure Ciphering ProcedureCiphering Procedure
TMSI Realloc Procedure TMSI Realloc Procedure TMSI Realloc Procedure
SETUP SETUPSETUP
Call Confirmed Call Confirmed
Assignment Procedure Assignment Procedure Assignment ProcedureAlertingAlertingAlerting
ConnectConnectConnect
Connect Ack. Connect Ack. Connect Ack.
Speech
Paging Response
PagingPaging CommandPaging Request ST3113
ET3113
Paging Group Number: defined by BS_AG_BLKS_RES and BS_PA_MFRMS;MS belong to the Paging Group = (IMSI mod 1000) mod N;MS only monitor its own Paging Group’s Pagi
ng Req message
( MS ID( TMSI+IMSI/IMSI), Cell ID( LAC/LAC+CI))
( MS ID( TMSI/IMSI), Paging Group)
( MS ID( TMSI/IMSI))( Max 4 TMSI)
( Mobile ID, Classmark2, Priority,)
( calling party nbr)
MTC
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Paging
IMSI, BSC use it for calculate Paging GroupTMSI, it’s save bits number in radio resource for Paging
LAC Paging
MTC —— A interface
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MS BTS BSC MSC
Clear CMD
ESTIN (Loc Up Req)
RR Connection Establishment RR Connection Establishment RR Connection Establishment
Authentication Procedure Authentication Procedure Authentication ProcedureCiphering Procedure Ciphering ProcedureCiphering Procedure
TMSI Realloc Procedure TMSI Realloc Procedure TMSI Realloc Procedure
Loc Up Accept
Channel ReleaseDeactivate SACCH
DISC
Release IndicationUA
RF Ch Release
Loc Up Req
Loc Up AcceptLoc Up Accept
Channel Release
RF Ch Release AckClear CMP
ST3210
ET3210
( LU Type, MS ID, LAI, Classmark1,)
Location Update
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Location Update Request
Location Update —— A interface
( Follow-on ) call procedure
Old LAC
Current TMSI
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MS BTS BSC MSCMeasurement Rep Measurement ResIntra cell HO
Phys Context ReqOC
OC Phys Context Conf
OC : Old ChannelNC : New Channel
NC
NC Channel Activation AckChannel Activation
Handover CommandAssignment Command
OC
SABMEstablish Indication
UA
OCNC
NCNC
Assignment Complete NCAssignment Complete
Handover Performed
RF Channel RelOC
RF Channel Rel Ack.OC
ST9108
ET9108
ST9103
ET9103
ST3107
ET3107
ST_RCR_ACK
ET_RCR_ACK
Old TA、 MS/BS_TxPwr will be reused in new chann
el
( HO Cause, Cell ID, Chn Type)
Intra Cell HO
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MS BTSserving BSC MSCBTStargetMeas Report Meas ResultHO Alarm & Candidate Cell
Phys Context Req
Phys Context Conf
Channel Activation
Channel Act Ack.
HO CommandHO Command
HO AccessHO Detection
SABMEstablish Ind
UA
Handover Complete Handover CompleteHandover Performed
RF Channel ReleaseRF Channel Rel. Ack.
ST9108
ET9108
ST9103
ET9103
ST3103
ST3103
ST3106
ET3106
ST_RCR_ACK
ET_RCR_ACK
ST200
ET200
Old TA is reused in new channel, but MS/BS_TxPwr will use the MAX in new channel
( AB, DCH)
( Cell, MA, MAIO, HSN, TS, TA)
Internal Inter Cell HO——Synchronized HO
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MS BTSserving BSC MSCBTStargetHO Alarm & Candidate Cell
Channel Activation
Channel Act Ack.
HO CommandHO Command
HO Access
HO Detection
SABM
Establish IndUA
Handover Complete Handover CompleteHandover Performed
RF Channel Release
RF Channel Rel. Ack.
ST9103
ET9103
ST3103
ST3103
ST3105
ET3105
Physical Info
ST3124
ET3124
ST200
ET200
ST_RCR_ACK
ET_RCR_ACK
Phys Context Req
Phys Context ConfST9108
ET9108
Meas Report Meas Result
No Physical Cont Req procedure, old channel TA can’t reuse for ne
w channel
Measure TA
( TA)( TA is reused)
Internal Inter Cell HO——asynchronous
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MS BTSserving BSCserving MSCBTStargetMeas Report Meas Result HO Alarm & Candidate Cell
Channel Activation
Channel Act Ack.
HO CommandHO Command
HO AccessHO Detection
SABMEstablish Ind
UAHandover Complete Handover Complete HO Complete
RF Channel Release
RF Ch. Rel. Ack.
BSCtarget
HO RequiredHO Request
HO Request Ack.HO Command
Phys Information
( SCCP Con Required)
( SCCP Con Conf) .
Clear Command
Clear Complete
SCCP Released
SCCP Rel. Cmp.
STrr2
ET3124
ETrr2
ST_HO_REQ_Lost
ST9103
ST9103
ST9113
ST3103
ET3103
ST3124
ST200
ET200
ST3106
ET3106
ST8
ET8
External Inter Cell HO
ET9113
ET_HO_REQ_Lost
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External Inter Cell HO——A interface
HO Command
Target cell: BCCH/BSIC
Target cell channel type
Use for HO AccessInitial power for new channel
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External Inter Cell HO——A interface
HO Request ( 2 of 2)Source cell
Priority and Queuing
A interface’s CIC
Target cell
Classmark3
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MS BTS BSC MSC
DisconnectDisconnect Disconnect
Release ReleaseRelease
Release Complete Release CompleteRelease Complete
MS release
DisconnectDisconnect Disconnect
Release ReleaseRelease
Release Complete Release CompleteRelease Complete
Network release
Channel Release
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Channel Release——A interface
A interface ——MS release
Call release( DTAP layer)
BSSM release
SCCP release Disconnect
MS release
Normal call clear
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Channel Release——A interface
A interface ——Network Release
Disconnect
Network release
Another side hung up
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Channel Release► Um and A interface release is separated with each other
Um Channel Release► BSC send Channel Release message to MS► Radio Link Failure
A interface Release► MSC send CLEAR COMMAD to BSC► BSC send CLEAR REQUEST to MSC
Channel Release
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MS BTS BSC MSC
DISC (DCH)
Channel Release (DCH)Deactivate SACCH
Release IndicationUA
Phy Context RequestPhy Context ConfirmRF Channel ReleaseRF Channel Release Ack
ET3110
ST3110
ST3111
T3111 ExpiryST9108
ET9108
ST_RCR_ACK
ET_RCR_ACK
BSC send Channel ReleaseTo MS
No SACCH received from the MSConnection Fail Ind
RF Channel ReleaseRF Channel Release Ack
ST_RCR_ACK
ET_RCR_ACK
Radio Link Failure
Wait for T3111 expired, then release BTS channel, to ensure the UA message have time to s
end
Channel Release ——Radio Channel
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MSCBSC
Clear Request
Clear Command
Clear Complete
SCCP Released
SCCP Released Complete
BSC Trigger the release
Clear Command
Clear Complete
SCCP Released
SCCP Released Complete
MSC Trigger the release
ST9104
ET9104
ST9101
ET9101
ST9101
ET9101
Channel Release——A Interface Release