1. Layer 3 Messaging and Call Procedures
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Layer 3 Messaging and Call Procedures
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2. Agenda Protocol Layers & Signaling Radio Network Procedures
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Agenda
Protocol Layers & Signaling
Radio Network Procedures
Example Call Flows
KPI Calculation Triggers

3. Channels Logical Channels – Defines what information to be transferred
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Channels
Logical Channels – Defines what information to be transferred
Transport Channels – Defines how data should be transferred.
Physical Channels – Carry the data

4. Protocol Layers L2/MAC L1 L2/RLC L3/RRC UTRAN UE RRC RLC MAC PHY CTRL
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Protocol Layers
L2/MAC L1
L2/RLC
L3/RRC
UTRAN UE
RRC
RLC
MAC
PHY
Signaling
Radio Bearer
Logical Channel
Transport Channel
Physical Channel
CTRL
USER
DATA

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Layer 3 Signaling
The Control Signaling is used for troubleshooting the problems. These messages are carried in the Logical Control Channels such as DCCH, CCCH, BCCH.
Radio Resource Control (RRC) Protocol messages contain the necessary control information and the commands – Obtained from TEMS.
In the Iub we may be interested in the NBAP and RANAP protocol messages – Obtained from UETR. CC SM CC SM MM
GMM MM
GMM
RRC
RRC
RANAP
RANAP
RLC/MAC
RLC/MAC
SCCP
SCCP
PHY
PHY
Sig. Bearer
Sig. Bearer UE
WRAN
MSC/VLR or SGSN

6. RRC Protocol Functions
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RRC Protocol Functions
Carries most of the Control Signaling between the UE and the UTRAN.
Carries all the information required to setup, modify and release lower layer entities.
RRC Controls
Radio Bearer parameters such as RLC Timers, QoS
Transport channel parameters such as the Transport format Combination (TFC)
Physical Channel parameters such as Code usage, carrier frequency
Radio Resource Supervision

7. RRC States RRC Connected Mode CELL_PCH CELL_FACH CELL_DCH IDLE MODE
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RRC States
RRC Connected Mode
CELL_PCH
CELL_FACH
IDLE MODE
CELL_DCH
RRC Connection Establishment
RRC Connection Release
Radio Bearer Reconfiguration

8. Layer 3 Procedures RRC Setup and RRC release Measurement Reports
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Layer 3 Procedures
RRC Setup and RRC release
Measurement Reports
Active Set Update
Radio Bearer Setup and Reconfiguration
Transport Channel Reconfiguration
Physical Channel Reconfiguration
All Call setup and tear down messages (such as PDP Activation/Deactivation, Alerting/Release etc) - These are Call Control and Session Management messages.

9. System Information Blocks (BCH)
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System Information Blocks (BCH)
RRC Protocol Schedules the SIBs.
The system information blocks are arranged as a tree structure. The Master Info. Block (MIB) contains the reference and scheduling info for the SIBs.
UE receives SIBs in Idle or CELL_FACH modes
MIB
SIB 1
SIB 3
SIB 5
SIB n
SIB n.1
SIB n.2
SIB 7
SIB 11
LA/ RA Updating, Paging, idle mode timers
CRS Parameters
Cell / Common Ch. Configuration
Power Control on Common Channels
Measurement Management

10. Measurement Procedures
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Measurement Procedures UE
RNC
RRC: Measurement Control (BCCH/DCCH)
UE Measures the SCs and performs Evaluation for Event Trigger Criteria.
RRC: Measurement Report (DCCH)
RNC Evaluates based on the measurements and Network Configuration.
RRC: Active Set Update (DCCH)
Remember !!! – Unlike GSM, the measurement reports event triggered. You can see long times of silence from the UE. These are not to be confused as missing messages.

11. RRC Connection Establishment
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RRC Connection Establishment UE
RNC
Cause Code for connection Request Sent:
•Originating Streaming Call
• Originating Interactive Call
• Originating Background Call
• Terminating Conversational Call
• Terminating Streaming Call
• Terminating Interactive Call
• Terminating Background Call
• Emergency Call
• Registration
• Originating High Priority Signalling
• Call re-establishment
• Terminating High Priority Signalling
• Terminating cause unknown
RRC: RRC Connection Request (CCCH)
RRC: RRC Connection Setup (CCCH)
RRC Connection can be rejected to Admission & Congestion Control Features
Contains the UE Capability (HS or R99)
RRC: RRC Connection Setup Complete (DCCH)
Cause codes will indicate the problem if RRC Connection is rejected

12. RRC Connection Establishment
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RRC Connection Establishment
UE starts timer T=0, counter N=1
UE sends RRC Connection Request
UE increments Timer T N
T >T300 Y
N = N + 1
T=0 Y
N > N300 N
UE gets RRC Connection Setup Y
UE sends RRC Connection Setup Complete
Fail. UE goes into idle mode N
RRC Procedure Successful
Why do we need T300 and N300 N
UE gets RRC Connection Reject Y
Cause = “Wait’ N Y
N = N + 1
T=0
UE sends RRC Connection Request
Wait for ‘wait’ seconds

13. Radio Bearer Setup UE RNC CN
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Radio Bearer Setup UE
RNC CN
RANAP: Radio Access Bearer Request
RRC: Radio Bearer Setup (DCCH)
RRC: Radio Bearer Setup Complete (DCCH)
RANAP: Radio Access Bearer Response (DCCH)
RAB (Radio Access Bearer) is setup between Core and UE.
Radio Bearer is setup between UE and UTRAN to support the RAB.

14. Active Set Update UE RNC
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Active Set Update UE
RNC
RRC: Measurement Report (e1a, e1b, e1c) (DCCH)
RRC: Active Set Update (DCCH)
Timeout of 5 s
RRC: Active Set Update Complete (DCCH)
UTRAN sends Active Set Update to the UE in CELL_DCH mode.
The result could be one of the following
Radio Link Addition
Radio Link Removal
Radio Link Replacement (Combined Addition/Removal)

15. Radio Bearer Reconfiguration
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Radio Bearer Reconfiguration UE
RNC
FACH/DCH
RRC: Radio Bearer Reconfiguration (DCCH)
DCH/FACH
RRC: Radio Bearer Reconfiguration Complete (DCCH)
RB Reconfiguration occurs for the following scenarios
Channel Type Switch i.e., DCH to FACH, FACH to DCH
Reconfiguration of the Radio Bearer after RB Setup (such as RLC timer reconfiguration)

16. Transport Channel Reconfiguration
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Transport Channel Reconfiguration UE
RNC
RRC: Transport Channel Reconfiguration (DCCH)
RRC: Transport Channel Reconfiguration Complete (DCCH)
Transport Channel Reconfiguration procedure triggers the Channel Rate Switching. 64K <-> 128K <-> 384K

17. Physical Channel Reconfiguration
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Physical Channel Reconfiguration UE
RNC
RRC: Physical Channel Reconfiguration (DCCH)
RRC: Physical Channel Reconfiguration Complete (DCCH)
Physical channel reconfiguration procedure is used to establish, reconfigure and release physical channels.
Used to enter Compressed mode before IRAT, HSDPA Cell Change

18. RRC Connection Release
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RRC Connection Release UE
RNC
RRC: RRC Connection Release (DCCH / CCCH)
RRC: RRC Connection Release Complete (CCCH)
RRC: RRC Connection Abnormal Release (DCCH / CCCH)
When the RRC Connection is released, the UE will be in IDLE mode. Radio Bearers will be released.
RRC Connection can be released abnormally if

19. Example Voice Call Flow (MOC)
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Example Voice Call Flow (MOC) UE
RNC
RRC: RRC Connection Request (CCCH)
RRC: RRC Connection Setup (CCCH)
Call Setup Phase
KPIs:
Call Setup Success Rate
Call Setup Time
RRC: RRC Connection Setup Complete (DCCH)
RRC: Initial Direct Transfer - CM Service Request (DCCH)
RRC: Downlink Direct Transfer – Auth & Ciph Request (DCCH)
RRC: Uplink Direct Transfer - Auth & Ciph Response (DCCH)
RRC: Security Mode Command (DCCH)
RRC: Security Mode Complete (DCCH)
RRC: Uplink Direct Transfer - SETUP (DCCH)
RRC: Downlink Direct Transfer – CALL PROCEEDING (DCCH)
Total Call Time
KPIs:
Dropped Call
RRC: Radio Bearer Setup (DCCH)
RRC: Radio Bearer Setup Complete (DCCH)
RRC: Downlink Direct Transfer – ALERTING (DCCH)
RRC: Downlink Direct Transfer - CONNECT (DCCH)
RRC: Downlink Direct Transfer – CONNECT ACK (DCCH)
RRC: Measurement Control (DCCH)
RRC: Measurement Report (DCCH)
RRC Connection is released after the Call Release.
RRC: Uplink Direct Transfer - DISCONNECT (DCCH)
RRC: Direct Transfer - Release (DCCH)
RRC: Uplink Direct Transfer – Release Complete (DCCH)

20. Example PS R99 Call Flow UE RNC Call Setup Phase KPIs:
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Example PS R99 Call Flow UE
RNC
RRC: RRC Connection Request (CCCH)
RRC: RRC Connection Setup (CCCH)
Call Setup Phase
KPIs:
Call Setup Success Rate
Call Setup Time
RRC: RRC Connection Setup Complete (DCCH)
RRC: Initial Direct Transfer - CM Service Request (DCCH)
RRC: Downlink Direct Transfer – Auth & Ciph Request (DCCH)
RRC: Uplink Direct Transfer - Auth & Ciph Response (DCCH)
RRC: Security Mode Command (DCCH)
RRC: Security Mode Complete (DCCH)
RRC: Uplink Direct Transfer – SM ACTIVATE PDP CONTEXT REQUEST (DCCH)
RRC: Radio Bearer Setup (DCCH)
Total Call Time
KPIs:
Dropped Call
RRC: Radio Bearer Setup Complete (DCCH)
RRC: Downlink Direct Transfer – SM ACTIVATE PDP CONTEXT ACCEPT (DCCH)
RRC: Transport Channel Reconfiguration (DCCH)
Channel Switching
RRC: Transport Channel Reconfiguration Complete (DCCH)
RRC: Measurement Control (DCCH)
RRC: Measurement Report (DCCH)
RRC: Uplink Direct Transfer – SM Deactivate PDP Context Request (DCCH)
RRC: Direct Transfer – SM Deactivate PDP Context Accept (DCCH)
RRC: RRC Connection Release (DCCH)

21. Example HSDPA Call Flow
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Example HSDPA Call Flow UE
RNC
RRC: RRC Connection Request (CCCH)
KPI
Call Setup Success Rate
Call Setup Time
RRC: RRC Connection Setup (CCCH)
RRC: RRC Connection Setup Complete (DCCH)
RRC: Uplink Direct Transfer – SM ACTIVATE PDP CONTEXT REQUEST (DCCH)
RRC: Downlink Direct Transfer – SM ACTIVATE PDP CONTEXT ACCEPT (DCCH)
RRC: Measurement Report (e1a) (DCCH)
E1A:
Radio Link Addition
RRC: Active Set Update (DCCH)
RRC: Active Set Update Complete (DCCH)
Not a HS Cell Change. Here the procedure is to realign the parameters.
RRC: Physical Channel Reconfiguration (DCCH)
RRC: Physical Channel Reconfiguration Complete (DCCH)
RRC: Measurement Report (e1d) (DCCH)
E1D:
Change of Best Server
RRC: Active Set Update (DCCH)
RRC: Active Set Update Complete (DCCH)
HS Cell Change
KPI
HS Cell Change Success Rate
HS Cell Change time
RRC: Physical Channel Reconfiguration (DCCH)
RRC: Physical Channel Reconfiguration Complete (DCCH)

22. Example IRAT Handover (PS)
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Example IRAT Handover (PS) UE
RNC
RRC: Uplink Direct Transfer – SM ACTIVATE PDP CONTEXT REQUEST (DCCH)
RRC: Uplink Direct Transfer – SM Alerting (DCCH)
RRC: Radio Bearer Setup (DCCH)
RRC: Radio Bearer Setup Complete (DCCH)
RRC: Downlink Direct Transfer – SM ACTIVATE PDP CONTEXT ACCEPT (DCCH)
RRC: Downlink Direct Transfer – Connect (DCCH)
RRC: Transport Channel Reconfiguration (DCCH)
RRC: Transport Channel Reconfiguration Complete (DCCH)
RRC: Measurement Control (DCCH)
RRC: Measurement Report (e1b) (DCCH)
RRC: Active Set Update (DCCH)
RRC: Active Set Update Complete (DCCH)
RRC: Transport Channel Reconfiguration (DCCH)
RRC: Transport Channel Reconfiguration Complete (DCCH)
UE Enters Compressed Mode, Starts measuring in GSM
RRC: Measurement Report (e2d) (DCCH)
RRC: Physical Channel Reconfiguration (DCCH)
RRC: Physical Channel Reconfiguration Complete (DCCH)
Handover to GSM. UE performs RA update in GSM
RRC: Measurement Control (DCCH)
Handover to GSM. Handover Complete message in GSM indicates successful Handover
RRC: Measurement Report (e3a) (DCCH)
RRC: Cell Change Order From UTRAN (DCCH)
RRC: Handover From UTRAN (DCCH)

23. CS IRAT Handover (Core Perspective)
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CS IRAT Handover (Core Perspective) UE
RNC
MSC/
MGW
BSC
RANAP: Relocation Required
RRC: Measurement Report (e3a) (DCCH)
BSSMAP: Handover Request
Timer: T_RELOC_Prep
BSSMAP: Handover Request Ack
RANAP: Relocation Command
RRC: Handover from UTRAN
RR: Handover Access
RR: Handover Complete
RANAP: Iu Release Command
RANAP: Iu Release Complete
If Relocation is cancelled due to “No resource available” – IRAT is cancelled but call is kept.
Relocation timer expires => GSM didn’t respond => IRAT cancelled but call is kept.

24. Example HSDPA/FACH Iur Handover
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Example HSDPA/FACH Iur Handover UE
RNC
RRC: Uplink Direct Transfer – SM ACTIVATE PDP CONTEXT REQUEST (DCCH)
RRC: Downlink Direct Transfer – SM ACTIVATE PDP CONTEXT ACCEPT (DCCH)
RRC: Measurement Report (e1a) (DCCH)
UE does Channel Type Switch to CELL_FACH
RRC: Active Set Update (DCCH)
RRC: Active Set Update Complete (DCCH)
RRC: Physical Channel Reconfiguration (DCCH)
RRC: Physical Channel Reconfiguration Complete (DCCH)
RRC: Radio Bearer Reconfiguration (DCCH)
RRC: Radio Bearer Reconfiguration Complete (DCCH)
RRC Establishment Cause Code:
“Call Re-Establishment” Or
“Directed Signalling Re-establishment”
RRC: Cell Update (CCCH)
RRC: RRC Connection Release (DCCH)
RRC: RRC Connection Request (CCCH)
RRC: RRC Connection Setup (CCCH)
RRC: RRC Connection Setup Complete (DCCH)
RRC: Radio Bearer Setup (DCCH)
RRC: Radio Bearer Setup Complete (DCCH)

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Some Abnormal Cases

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Abnormal Drop Case
UETR
TEMS LOGS from UE

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KPI Definitions

28. KPI Definition – CS Drop
Total Call Duration
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KPI Definition – CS Drop
AMR
RRC Connection Request
RRC Connection Setup Complete
Alerting
Disconnect
Connect
Event = Dropped Call
Dedicated Mode To Idle Mode
RRC Connection Abnormal Release
CS Dropped Call Rate (Long Call) =
Effective Calls = Total Call Duration / 90 sec (MHT)

29. KPI Definition – PS Drop
Total Call Duration
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KPI Definition – PS Drop
Packet Call
RRC Connection Request
RRC Connection Setup Complete
Activate PDP Context Accept
Session Start
(TEMS Internal)
Session End/Error
(TEMS Internal)
Deactivate PDP Context Req/Accept
RRC Connection Request
/RRC Connection Setup Complete
RRC Connection Request
/RRC Connection Setup Complete
PS Drop Rate (Long Calls) =
Effective Calls = Total Call Duration / 60 sec (MHT)

30. KPI Definition – Call Setup Success
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KPI Definition – Call Setup Success
RRC Connection Request
RRC Connection Setup Complete
Alerting
RRC Connection Reject
No Alerting Or Connect
RRC Connection Request Exceeds N300
AMR
If total time between RRC Connection Request And Connect Exceeds 50 Seconds (setup timeout) = Access Failure
RRC Connection Request
RRC Connection Setup Complete
Activate PDP
Context Accept
RRC Connection Reject
No Activate PDP Context Accept
/Session Start
RRC Connection Request Exceeds N300
Packet Call
If total time between RRC Connection Request And Session Start Exceeds 50 Seconds (setup timeout) = Access Failure

31. KPI Definition - Throughput
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Session Duration
KPI Definition - Throughput
Session Duration
Activate PDP Context Accept
Session Start
(TEMS Internal)
Session Start
(TEMS Internal)
Session End/Error
(TEMS Internal)
Session End/Error
(TEMS Internal)
Deactivate PDP Context Req/Accept
RRC Connection Request
/RRC Connection Setup Complete

32. KPI Definition - IRAT UMTS To GSM CS Handover UMTS To GSM PS Handover
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KPI Definition - IRAT
GSM
UMTS
Handover Command Inter System To Utran
Handover Access
Handover Complete
Measurement Report
UMTS To GSM CS Handover
GSM/GPRS
UMTS
Cell Change Order from UTRAN Command
Routing Area Update Request
Routing Area Update Accept
Measurement
Report
UMTS To GSM PS Handover

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