Fast CS Fallback Based on RIM(RAN14.0_02)

Fast CS Fallback Based on RIM RAN14.0

Feature Parameter Description

Issue 02

Date 2012-07-20

HUAWEI TECHNOLOGIES CO., LTD.

Copyright Huawei Technologies Co., Ltd. 2012. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior

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Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.

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holders.

Notice

The purchased products, services and features are stipulated by the contract made between Huawei and

the customer. All or part of the products, services and features described in this document may not be

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information, and recommendations in this document are provided "AS IS" without warranties, guarantees or

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Huawei Technologies Co., Ltd.

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Email: [email protected]

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WCDMA RAN

Fast CS Fallback Based on RIM Contents

Issue 02 (2012-07-20) Huawei Proprietary and Confidential

Copyright Huawei Technologies Co., Ltd.

i

Contents

1 Introduction ................................................................................................................................ 1-1

1.1 Scope ............................................................................................................................................ 1-1

1.2 Intended Audience......................................................................................................................... 1-1

1.3 Change History .............................................................................................................................. 1-1

2 Overview...................................................................................................................................... 2-1

3 Technical Description .............................................................................................................. 3-1

4 Related Features ....................................................................................................................... 4-1

4.1 Required Features......................................................................................................................... 4-1

4.2 Mutually Exclusive Features ......................................................................................................... 4-1

4.3 Affected Features .......................................................................................................................... 4-1

5 Impact on the Network............................................................................................................. 5-1

5.1 Impact on System Capacity........................................................................................................... 5-1

5.2 Impact on Network Performance ................................................................................................... 5-1

6 Engineering Guidelines ........................................................................................................... 6-1

6.1 When to Use Fast CS Fallback Based on RIM ............................................................................. 6-1

6.2 Deploying Fast CS Fallback Based on RIM .................................................................................. 6-1

6.3 Performance Optimization ............................................................................................................. 6-2

6.4 Troubleshooting ............................................................................................................................. 6-2

7 Parameters.................................................................................................................................. 7-1

8 Counters ...................................................................................................................................... 8-1

9 Glossary ...................................................................................................................................... 9-1

10 Reference Documents ......................................................................................................... 10-1

WCDMA RAN

Fast CS Fallback Based on RIM 1 Introduction



1-1

1 Introduction

1.1 Scope

This document describes the feature WRFD-140224 Fast CS Fallback Based on RIM, including working principles, network impact, and engineering guidelines. RIM is short for RAN information management.

1.2 Intended Audience

This document is intended for:

Personnel who need to understand Fast CS Fallback Based on RIM

Personnel who work with Huawei products

1.3 Change History

Document Issues

The document issue is as follows:

02 (2012-07-20)

01 (2012-04-30)

02 (2012-07-20)

This is the document for the second commercial release of RAN14.0.

Compared with issue 01 (2012-04-30) of RAN14.0, this issue this issue incorporates the changes described in the following table:

Change Type

Change Description Parameter Change

Feature change

None. None.

Editorial change

Added the information about how to deploy the feature. For details, see 6.2 Deploying Fast CS Fallback Based on RIM.

None.

01 (2012-04-30)

This is the first commercial release of RAN14.0.

This is a new document.

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Fast CS Fallback Based on RIM 2 Overview



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2 Overview

In the initial phase of LTE deployment, the LTE network may support only data services because the IP multimedia subsystem (IMS) is usually not deployed. If a UE initiates a CS service in such a network, the service needs to be transferred to a UMTS or GSM network by CS fallback (CSFB). CSFB can be based on redirection or PS handover.

In PS-handover-based CSFB, UEs can access the target UMTS cell without delay because the radio resources have been ready before CSFB is performed. However, UEs in redirection-based CSFB experience longer delays because the UMTS connection can be established only after the LTE connection is released. Fast CS Fallback Based on RIM shortens the delay in redirection-based CSFB by transmitting system information of the neighboring UMTS cells of the LTE cell to the eNodeB before CSFB is performed. When a UE initiates a CS service and redirection-based CSFB needs to be performed, the eNodeB sends the UE an RRC Connection Release message that contains the system information of the target UMTS cell. Upon receiving the message, the UE can access the target UMTS cell by sending an RRC Connection Request message.

NOTE

RIM, available since 3GPP Release 5, enables message interaction between the GERAN, UTRAN, and E-UTRAN.

Figure 2-1 shows the procedure for Fast CS Fallback Based on RIM.

Figure 2-1 Procedure for Fast CS Fallback Based on RIM

The procedure for Fast CS Fallback Based on RIM is as follows:

1. The eNodeB obtains the system information of the neighboring UMTS cells of the LTE cell by using the RIM procedures.

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Fast CS Fallback Based on RIM 2 Overview



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2. When a UE initiates a CS service and CSFB needs to be performed, the eNodeB sends the UE an RRC Connection Release message that contains the frequency, primary scrambling code, and system information of the target UMTS cell.

3. Upon receiving the message, the UE sends the target UMTS cell an RRC Connection Request message without reading the cell system information.

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Fast CS Fallback Based on RIM 3 Technical Description



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3 Technical Description

Fast CS Fallback Based on RIM requires data configurations on both the RNC and eNodeB sides. Whether to enable Fast CS Fallback Based on RIM on the RNC side is specified by the parameter PROCESSSWITCH2: FAST_CS_FB_BASEDON_RIM_SWITCH. To learn about how to enable Fast CS Fallback Based on RIM on the Huawei eNodeB side, see the CSFB Feature Parameter Description for eRAN.

When the switch PROCESSSWITCH2: FAST_CS_FB_BASEDON_RIM_SWITCH is turned off, the RNC supports fast

CS fallback based on RIM. When the switch is turned on, the RNC does not support fast CS fallback based on RIM.

Figure 3-1 shows the signaling flowchart for Fast CS Fallback Based on RIM.

Figure 3-1 Signaling flowchart for Fast CS Fallback Based on RIM

The signaling procedure for Fast CS Fallback Based on RIM is as follows:

1. The eNodeB obtains the system information of the neighboring UMTS cells of the LTE cell.

When the LTE cell is configured with neighboring UMTS cells and Fast CS Fallback Based on RIM is enabled on the eNodeB side, the eNodeB obtains the initial system information of the UMTS cells as follows:

1) The eNodeB sends the RNC a RAN-INFORMATION-REQUEST/Multiple Report message that contains the information elements (IEs) RIM Application Identity and Reporting Cell Identifier. The value of the RIM Application Identity IE contained in the message is UTRA System Information, which indicates that the eNodeB needs to obtain the system information of the UMTS cells. The Reporting Cell Identifier IE specifies the UMTS cells whose system information needs to be obtained.

2) Upon receiving the message, the RNC responds with a RAN-INFORMATION/Multiple Report Initial message and sends the eNodeB another RAN-INFORMATION/Multiple Report message that contains the MIB, SIB1, SIB3, SIB5, and SIB7 of the requested UMTS cells.

../RNCParaHtml/mbsc/m-para/urrctrlswitch_processswitch2.html../RNCParaHtml/mbsc/m-para/urrctrlswitch_processswitch2.html

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Fast CS Fallback Based on RIM 3 Technical Description



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When the MIB, SIB1, SIB3, SIB5, or SIB7 (except for the UL interference IE in SIB7) is changed, the eNodeB obtains the updated system information of the UMTS cells as follows:

1) The RNC sends the eNodeB a RAN-INFORMATION-REQUEST/Multiple Report message that contains the updated system information.

2) The eNodeB responds with a RAN-INFORMATION-ACK message to acknowledge the receipt of the message.

NOTE

The UL interference IE in SIB7 is one of the factors that determine the UE initial access level. The value of this IE frequently changes with the network traffic conditions. To prevent a large amount of system information update procedures caused by uplink interference, the RNC always sends the eNodeB the value of -105 dBm as the value of the UL interference IE. It is worth noting that this may decrease the RRC connection setup success rate when the UMTS uplink load is heavy.

2. The eNodeB delivers the system information of the target UMTS cell to the UE.

When a UE initiates a CS service in the LTE network and the service needs to be transferred to the UMTS network by redirection-based CSFB, the eNodeB sends the UE an RRC Connection Release message that contains the frequency, primary scrambling code, and system information of the target UMTS cell.

3. The UE accesses the target UMTS cell by sending an RRC Connection Request message.

The UE sends the RNC an RRC Connection Request message after receiving the RRC Connection Release message. If the value of the IE System Information Container Stored Indication contained in the message is TRUE, the UE complies with 3GPP Release 9 and supports Fast CS Fallback Based on RIM. Upon receiving the RRC Connection Request message from the UE, the RNC transits the UE to the CELL_DCH state. The RNC does not transit the UE to the CELL_FACH state because the UE behaviors in the CELL_FACH state are unspecific and the transition to the CELL_FACH state may cause compatibility issues.

The signaling procedure for ending the RIM procedure is as follows:

When a neighboring UMTS cell is removed from the eNodeB, the eNodeB no longer obtains the system information of the cell. In this case, the RIM procedure is ended as follows:

1) The eNodeB sends the RNC a RAN-INFORMATION-REQUEST/stop message, instructing the RNC to end the RIM procedure.

2) Upon receiving the message, the RNC responds with a RAN-INFORMATION/Stop message and stops sending the system information of the removed neighboring UMTS cell to the eNodeB.

When a UMTS cell is removed from the RNC, the eNodeB does not obtain the system information of the cell. In this case, the RIM procedure is ended as follows:

1) The RNC sends the eNodeB a RAN-INFORMATION/End message, instructing the eNodeB to end the RIM procedure.

2) Upon receiving the message, the eNodeB responds with a RAN-INFORMATION-ACK message and ends the RIM procedure.

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Fast CS Fallback Based on RIM 4 Related Features



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4 Related Features

4.1 Required Features

Fast CS Fallback Based on RIM requires the LTE feature LOFD-001052 Flash CS Fallback to UTRAN. If the eNodeB is not provided by Huawei, this feature is compatible with the feature Flash CSFB to UTRAN of the vendor, because Fast CS Fallback Based on RIM is developed based on standard protocols.

Fast CS Fallback Based on RIM must be enabled on both the RNC and eNodeB sides. If Fast CS Fallback Based on RIM is not enabled on the eNodeB side, do not enable it on the RNC side. Otherwise, the unnecessary RIM procedures initiated by the RNC will waste resources.

4.2 Mutually Exclusive Features

None.

4.3 Affected Features

The eNodeB can apply the system information of the UMTS cells obtained by RIM procedures to other types of LTE-to-UMTS redirections, such as load- and coverage-based PS redirections. This helps shorten the redirection duration by up to 1.28 seconds. The load- and coverage-based PS redirections relate to the following LTE features:

LOFD-001019 PS Inter-RAT Mobility between E-UTRAN and UTRAN

LOFD-001044 Inter-RAT Load Sharing to UTRAN

WCDMA RAN

Fast CS Fallback Based on RIM 5 Impact on the Network



5-1

5 Impact on the Network

5.1 Impact on System Capacity

No impact.

5.2 Impact on Network Performance

The impact of this feature on network performance is as follows:

Fast CS Fallback Based on RIM reduces the CSFB delay by up to 1.28 seconds.

The RRC connection setup success rate may slightly decrease. This is because the RNC always sends the eNodeB the value of -105 dBm as the value of the IE UL interference no matter how the value is changed. When the UMTS uplink interference is higher than this value, the uplink PRACH transmit power of the UE will experience a ramping procedure, which reduces the RRC connection setup success rate.

The procedures for obtaining the initial system information of the UMTS cells increase the load on the RNC, core network (CN), and Iu interface. Therefore, Fast CS Fallback Based on RIM is recommended during off-peak hours. The procedures for obtaining the updated system information have minor impacts on the load on the RNC, CN, and Iu interface. This is because the MIB, SIB1, SIB3, SIB5, and SIB7 (except for the UL interference IE in SIB 7) barely change.

When the system information of a UMTS cell (for example, the physical channel parameters in SIB5) is changed and faults occur during the RIM procedures (for example, the CN or the transmission between the RNC and eNodeB is faulty), Fast CS Fallback Based on RIM prolongs the UE access delay. This is because a UE in this case needs to autonomously reselect a target UMTS cell for redirection and read the cell system information.

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Fast CS Fallback Based on RIM 6 Engineering Guidelines



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6 Engineering Guidelines

6.1 When to Use Fast CS Fallback Based on RIM

Fast CS Fallback Based on RIM can be enabled when all of the following conditions are met:

The IMS is not deployed in the LTE network so that CS services need to be transferred to the UMTS network by CSFB.

PS handovers are not available, or UEs do not support PS handovers in the LTE network.

Fast CS Fallback Based on RIM is enabled on the LTE side. The related Huawei LTE feature is LOFD-001052 Flash CS Fallback to UTRAN.

Using Fast CS Fallback Based on RIM generates a large amount of signaling. To minimize the feature impact, it is recommended that this feature be used during off-peak hours.

6.2 Deploying Fast CS Fallback Based on RIM

This section describes how to activate, verify, and deactivate the basic feature WRFD-140224 fast CS fallback based on RIM. For details about how to configure this feature on the LTE side, see the related documents provided by the LTE equipment vendor.

Prerequisites

Dependencies on Hardware

This feature does not have any special requirements for hardware.

Dependencies on Other Features

This feature does not depend on other features.

License

The license "Fast CS Fallback Based on RIM" on the BSC6900 side has been activated. For details about the license items and how to activate the license, see License Management Feature Parameter Description.

Other Prerequisites

The UE must support flash CSFB in Release 9.

The mobility management entity (MME) and serving GPRS support node (SGSN) must support the RIM procedure in 3GPP release 9. If the core network (CN) is earlier than 3GPP release 9, it must support eNodeB ID conversion.

Procedure

Activation Procedure

1. Configure the data on the LTE side, including setting the neighbor relationships between cells.

2. For details about how to configure this feature on the LTE side, see the related documents provided by the LTE equipment vendor. If the LTE equipment is provided by Huawei, see the LTE document CS Fallback Parameter Description.

3. Run the BSC6900 MML command SET URRCTRLSWITCH (CME single configuration: UMTS Radio Global Configuration Express > Process Switch Configuration > Process Switch; CME batch modification center: Modifying RNC Parameters in Batches). In this step, select FAST_CS_FB_BASEDON_RIM_SWITCH under Process Control Switch 2 to enable this feature.

Verification Procedure

1. Trace the Iu-interface and UE signaling on the RNC LMT. Trace the S1 interface signaling (on the eNodeB LMT for Huawei eNodeBs) and the UE signaling (on the M2000 for Huawei eNodeBs).

License%20Management.htmLicense%20Management.htm../omc/cme/express/rnc-batch.html

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2. Verify that the Direct Information Transfer message that contains RAN-INFORMATION PDU REQUEST or RAN-INFORMATION PDU REPORT is transmitted over the Iu and S1 interfaces.

3. Initiate a CS service in an LTE cell. Check the UE signaling and verify that the IE CellInfoListUTRA-FDD-r9 in the RRC Connection Release message contains the frequency, primary scrambling code, and system information (including MIB, SIB1, SIB3, SIB5, and SIB7) of the target UMTS cell.

4. Check the UE log and measure the duration between the UE receiving an RRC Connection Release from the eNodeB and the UE sending an RRC Connection Request to the target UMTS cell. Verify that during this duration the UE does not read the system information of the target UMTS cell, and that this duration is shorter than the duration measured when Fast CS Fallback Based on RIM is disabled.

5. Check the UE signaling and verify that the RNC sends the UE an RRC_RB_SETUP message that contains the IE rrc-StateIndicator and instructs the UE to move to the CELL_DCH state.

Deactivation Procedure

1. Run the BSC6900 MML command SET URRCTRLSWITCH (CME single configuration: UMTS Radio Global Configuration Express > Process Switch Configuration > Process Switch; CME batch modification center: Modifying RNC Parameters in Batches). In this step, clear FAST_CS_FB_BASEDON_RIM_SWITCH under Process Control Switch 2 to disable this feature.

Example

//Activating fast CS fallback based on RIM

SET URRCTRLSWITCH: PROCESSSWITCH2=FAST_CS_FB_BASEDON_RIM_SWITCH-0;

//Deactivating fast CS fallback based on RIM

SET URRCTRLSWITCH: PROCESSSWITCH2=FAST_CS_FB_BASEDON_RIM_SWITCH-1;

6.3 Performance Optimization

Monitoring

After the parameters in the UMTS cell system information (for example, reselection parameters) are changed, if the value of the counter VS.IU.RanInfo.Tx in the corresponding UMTS cell does not increase, the parameter change does not take effect or the message for sending the updated system information is discarded by flow control.

The RRC connection setup success rate for Fast CS Fallback Based on RIM is equal to VS.RRC.Estab.CSFBWithSysStoredInd.Succ divided by VS.RRC.Estab.CSFBWithSysStoredInd.Att. If this rate is smaller than the total RRC connection setup success rate, the system information of neighboring UMTS cells stored on the eNodeB may be incorrect.

Parameter Optimization

N/A

6.4 Troubleshooting

After an RNC is reset and the UMTS cell system information is changed, the RNC may not inform the eNodeB of the updated system information. In this case, the eNodeB sends the stored system information to the UE for CSFB, and as a result the UE may fail to access the target UMTS cell and the redirection duration is prolonged. This case especially occurs when the channel format in SIB5 of the target UMTS cell is changed and the RNC does not inform the eNodeB. When this happens, the RNC cannot receive the RRC Connection Request message from the UE and the UE access fails. To solve this problem, the RIM procedure must be ended and then restarted on the LTE side so that the eNodeB

../omc/cme/express/rnc-batch.html

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can obtain the latest UMTS cell system information. To learn about how to do this for Huawei eNodeBs, see the CSFB Feature Parameter Description for eRAN.

When the CN or the transmission between the RNC and eNodeB is faulty, end the RIM procedure and then restart it on the LTE side so that the eNodeB can obtain the latest UMTS cell system information.

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Fast CS Fallback Based on RIM 7 Parameters



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7 Parameters

Table 7-1 Parameter description

Parameter ID NE MML Command

Feature ID Feature Name Description

PROCESSSWITCH2

BSC6900 SET URRCTRLSWITCH

WRFD-010101

WRFD-140224

3GPP R9 Specifications

Fast CS Fallback Based on RIM

Meaning:1) LOAD_IRAT_HO_RNC_FILL_TL (Cell Load Information TL Input Switch)

During inter-RAT handovers from 3G cells to 2G cells, the BSC6900 can records information about load on 3G cells in the RELOCATION REQUIRED container in the Tag Length Value (TLV) format.

When the switch is turned on, the BSC6900 records the Tag Length in the container.

When the switch is turned off, the BSC6900 does not record the Tag Length.

2) SEND_IDT_JUDGE_IU_RESET (Switch for Transferring INITIAL UE Messages in the IU Reset State)

When the switch is turned on, the BSC6900 discards the INITIAL UE message from a CN node if the Iu interface is in the reset state.

When the switch is turned off, the BSC6900 handles the INITIAL UE message from a CN node if the Iu interface is in the reset state.

3) RNC_RBRECFG_DRD_FAIL_ROLLBACK_SWITCH (RB Reconfiguration DRD

../RNCParaHtml/mbsc/m-para/urrctrlswitch_processswitch2.html../RNCParaHtml/mbsc/m-para/urrctrlswitch_processswitch2.html../RNCParaHtml/mbsc/m-mml/set-urrctrlswitch.html../RNCParaHtml/mbsc/m-mml/set-urrctrlswitch.html../RNCParaHtml/mbsc/m-mml/set-urrctrlswitch.html

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Rollback Switch)

When the switch is turned on, the BSC6900 supports rollback caused by failed directed retry decisions (DRDs) of RB reconfiguration.

When the switch is turned off, the BSC6900 does not support rollback caused by failed DRDs of RB reconfiguration.

4) RNC_CS_QUERY_UE_IMEI_SWITCH (CS IMEI Request Switch)

When this switch is turned on, the BSC6900 rather than the CN sends an IDENTITY REQUEST message to obtain the international mobile equipment identity (IMEI) of a UE. Note: When the CN checks the serial number of direct transfer messages and the SEND_MSG_NULL_SWITCH switch is turned off, turning on this switch leads to inconsistency in the serial number of direct transfer messages between the CN and the UE. This causes CS service setup failures. Therefore, you are not advised to turn on this switch. Before turning on this switch, test the interworking between the BSC6900 and the CN. If the CN checks the serial number of direct transfer messages, turn on SEND_MSG_NULL_SWITCH under "PROCESSSWITCH4" in the "SET URRCTRLSWITCH"

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command.

When the switch is turned off, the BSC6900 does not send an IDENTITY REQUEST message to obtain the IMEI of a UE.

5) RNC_PS_QUERY_UE_IMEI_SWITCH (PS IMEI Request Switch)

When the switch is turned on, the BSC6900, rather than the CN, sends an IDENTITY REQUEST message to obtain the IMEI of a UE.

When the switch is turned off, the BSC6900 does not send an IDENTITY REQUEST message to obtain the IMEI of a UE.

6) FACH_DTCH_CONGEST_P2D (P2D Switch for Congested FACH or DTCH)

When the switch is turned on, UEs using PS services trigger the CELL_PCH-to-CELL_DCH procedure (P2D procedure for short) on a congested FACH or DTCH.

When the switch is turned off, UEs using PS services do not trigger the P2D procedure on a congested FACH or DTCH.

7) RNC_RBSETUP_DRD_FAIL_ROLLBACK_SWITCH (RB Establishment DRD Rollback Switch)

When the switch is turned on, the BSC6900 supports rollback caused by failed

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DRDs of RB establishment.

When the switch is turned off, the BSC6900 does not support rollback caused by failed DRDs of RB establishment.

8) PS_NOTIFYCN_NOTDOWNSIZE_SWITCH (Switch for Not Triggering Rate Reduction Negotiation Between the CN and the RNC After a PS Service Access Failure)

When the switch is turned on, the access rate is not negotiated between the BSC6900 and the CN if a PS service fails to be admitted.

When the switch is turned off, the access rate is negotiated between the BSC6900 and the CN if a PS service fails to be admitted.

9) ASU_RSP_TIMEOUT_HANDLE_SWITCH (Switch for Performing the Optimized Soft-Handover Timeout Procedure)

When the switch is turned on, the RNC considers that it has received an ACTIVE SET UPDATE COMPLETE message during soft handover procedure after the message has expired.

When the switch is turned off, RABs are directly released during soft handover procedure after the ACTIVE SET UPDATE COMPLETE message has expired.

10)

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RB_RECFG_USER_INACT_SWITCH (Switch for Performing the Optimized RRC Connection Release Procedure with No Data Transmitted on the UE upon UE State Transition Timeout)

When the switch is turned on, the RNC initiated the release process with the cause of user inactive when the UE have no data to transmit.

When the switch is turned off, the RNC initiated the release process with other causes when the UE have no data to transmit.

11) RRC_SCRI_NORM_REL_SWITCH (Switch for Performing the Optimized RRC Connection Release Procedure on Receipt of a SIGNALLING CONNECTION RELEASE INDICATION Message)

When the switch is turned on, the RNC initiated the normal release process after receive SIGNALLING CONNECTION RELEASE INDICATION message from UE.

When the switch is turned off, the RNC does not handle SIGNALLING CONNECTION RELEASE INDICATION message during the process.

12) CELLUPT_RLFAILURE_SRBREESTAB_SWITCH (Switch for SRB Reestablishment During a Cell Update with the Cause Value of RL Failure)

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When the switch is turned on, SRBs are reestablished during cell update procedure with the "RL Failure" cause value.

When the switch is turned off, SRBs are not reestablished during cell update procedure with the "RL Failure" cause value.

13) CU_OVERLAP_DSCR_SWITCH (Switch for Performing the Optimized Procedure for Concurrent RB and Cell Update, Hard handover, or DRD)

When the switch is turned on, the DSCR procedure is performed if RNC can not handles different processes performed simultaneously.

When the switch is turned off,the DSCR procedure is not performed in this scenes.

14) TRB_RST_DSCR_SWITCH (Switch for Performing the Optimized TRB Reset Procedure for PS BE Services)

When the switch is turned on, the DSCR procedure is performed if a Layer 2 data transmission error occurs.

When the switch is turned off, the DSCR procedure is not performed if a Layer 2 data transmission error occurs.

15) RNC_FD_SCRI_FORCE_REL_SWITCH (Signaling Connection Release Switch for UEs Supporting

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Fast Dormancy)

When the switch is turned on, if the BSC6900 receives a SIGNALING CONNECTION RELEASE INDICATION from UE with the cause of "UE Requested PS Data session end", the BSC6900 triggers the state transition for the UE. Otherwise, the BSC6900 releases the signaling connection.

When the switch is turned off, if the BSC6900 receives a SIGNALING CONNECTION RELEASE INDICATION from UE, the BSC6900 triggers the state transition for the UE.

16) USRPLN_PRORATION_SHARED_ALO (Algorithm Switch for Inter-Subrack Load Sharing on the User Plane)

When the switch is turned on, load sharing can be performed based on the ratio of available user plane resources to total user plane resources in a subrack.

When the switch is turned off, load sharing cannot be performed based on the ratio of available user plane resources to total user plane resources in a subrack.

17) FP_IUUP_TRACE_SWITCH (Switch for Tracing UEs Failing in FP Synchronization)

When the switch is turned on, UEs using FP or Iu UP

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can be traced in terms of data streams.

When the switch is turned off, UEs using FP or Iu UP cannot be traced in terms of data streams.

18) RNC_PCHR_OUTPUT_CTRL_SWITCH (Switch for Reducing PCHR Log Information for Normal Procedure)

The switch RNC_PCHR_OUTPUT_CTRL_SWITCH controls whether the BSC6900 reduces information recorded in a PCHR log for a normal procedure.

When this switch is turned on, the BSC6900 reduces information in a performance call history record (PCHR) log recorded during a normal procedure and reports only the following information blocks:

-RRC_RELEASE

-CS_RAB_SETUP

-PS_RAB_SETUP

-CS_RAB_REL

-PS_RAB_REL

-SHO

-SYS_HO_OUT

-INTRA_FREQ_NET_OPT

-STAT

-CS_RAB_QUALITY_STAT

-PS_RAB_QUALITY_STAT

A procedure is abnormal only when either of the

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following conditions is met:

-The RRC connection setup fails.

-The RAB setup fails.

-The RAB is abnormally released.

-The value of the information element (IE) NAS-PDU contained in a DIRECT TRANSFER message is ATTACH REJECT, RAU REJECT, or LAU REJECT.

If this switch is turned off, the BSC6900 does not reduce information recorded in a PCHR log.

19) DTMF_SWITCH (DTMF Switch)

When the switch is turned on, the BSC6900 starts tracing after receiving a special RANAP_DIRECT_TRANSFER message from a UE.

When the switch is turned off, the BSC6900 does not start tracing after receiving a special RANAP_DIRECT_TRANSFER message from a UE.

20) FAST_CS_FB_BASEDON_RIM_SWITCH (Switch for fast CSFB based on RIM)

When the switch is turned off, the BSC6900 supports fast CSFB(CS fallback) based on RIM.

When the switch is turned on, the BSC6900 does not support fast CSFB(CS fallback) based on RIM.

GUI Value

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7-10



Range:LOAD_IRAT_HO_RNC_FILL_TL, SEND_IDT_JUDGE_IU_RESET, RNC_RBRECFG_DRD_FAIL_ROLLBACK_SWITCH, RNC_CS_QUERY_UE_IMEI_SWITCH, RNC_PS_QUERY_UE_IMEI_SWITCH, FACH_DTCH_CONGEST_P2D, RNC_RBSETUP_DRD_FAIL_ROLLBACK_SWITCH, PS_NOTIFYCN_NOTDOWNSIZE_SWITCH, ASU_RSP_TIMEOUT_HANDLE_SWITCH, RB_RECFG_USER_INACT_SWITCH, RRC_SCRI_NORM_REL_SWITCH, CELLUPT_RLFAILURE_SRBREESTAB_SWITCH, CU_OVERLAP_DSCR_SWITCH, TRB_RST_DSCR_SWITCH, RNC_FD_SCRI_FORCE_REL_SWITCH, USRPLN_PRORATION_SHARED_ALO, FP_IUUP_TRACE_SWITCH, RNC_PCHR_OUTPUT_CTRL_SWITCH, DTMF_SWITCH, FAST_CS_FB_BASEDON_RIM_SWITCH

Actual Value Range:LOAD_IRAT_HO_RNC_FILL_TL, SEND_IDT_JUDGE_IU_RESET, RNC_RBRECFG_DRD_FAIL_ROLLBACK_SWITCH, RNC_CS_QUERY_UE_IMEI_SWITCH, RNC_PS_QUERY_UE_IMEI_SWITCH,

WCDMA RAN




7-11



FACH_DTCH_CONGEST_P2D, RNC_RBSETUP_DRD_FAIL_ROLLBACK_SWITCH, PS_NOTIFYCN_NOTDOWNSIZE_SWITCH, ASU_RSP_TIMEOUT_HANDLE_SWITCH, RB_RECFG_USER_INACT_SWITCH, RRC_SCRI_NORM_REL_SWITCH, CELLUPT_RLFAILURE_SRBREESTAB_SWITCH, CU_OVERLAP_DSCR_SWITCH, TRB_RST_DSCR_SWITCH, RNC_FD_SCRI_FORCE_REL_SWITCH, USRPLN_PRORATION_SHARED_ALO, FP_IUUP_TRACE_SWITCH, RNC_PCHR_OUTPUT_CTRL_SWITCH, DTMF_SWITCH, FAST_CS_FB_BASEDON_RIM_SWITCH

Unit:None

Default Value:LOAD_IRAT_HO_RNC_FILL_TL-0&SEND_IDT_JUDGE_IU_RESET-0&RNC_RBRECFG_DRD_FAIL_ROLLBACK_SWITCH-0&RNC_CS_QUERY_UE_IMEI_SWITCH-0&RNC_PS_QUERY_UE_IMEI_SWITCH-0&FACH_DTCH_CONGEST_P2D-0&RNC_RBSETUP_DRD_FAIL_ROLLBACK_SWITCH-0&PS_NOTIFYCN_NOTDOWNSIZE_SWITCH-0&ASU_RSP_TIMEOUT_HANDLE_SWITCH-0&RB_RECFG_USER_INACT_SWITCH-0&RRC_SCRI_NORM_REL_SWITCH-0&CELLUPT_RLFAILURE_SRBREESTAB_SW

WCDMA RAN




7-12



ITCH-0&CU_OVERLAP_DSCR_SWITCH-0&TRB_RST_DSCR_SWITCH-0&RNC_FD_SCRI_FORCE_REL_SWITCH-0&USRPLN_PRORATION_SHARED_ALO-0&FP_IUUP_TRACE_SWITCH-1&RNC_PCHR_OUTPUT_CTRL_SWITCH-1&DTMF_SWITCH-1&FAST_CS_FB_BASEDON_RIM_SWITCH-1

WCDMA RAN

Fast CS Fallback Based on RIM 8 Counters



8-1

8 Counters

Table 8-1 Counter description

Counter ID

Counter Name Counter Description NE Feature ID Feature Name

73425017 VS.RRC.AttConnEstab.WithSI.CsDomain

Number of RRC Connection Setup Requests that carried System Information Container Stored Indication for CS services

BSC6900

WRFD-140224


73425018 VS.RRC.SuccConnEstab.WithSI.CsDomain

Number of Successful RRC Connection Setups for CS services (RRC Connection Setup Requests that carried System Information Container Stored Indication)

BSC6900

WRFD-140224


73425019 VS.RRC.AttConnEstab.WithSI.PsDomain

Number of RRC Connection Setup Requests that carried System Information Container Stored Indication for PS services

BSC6900

WRFD-140224


73425020 VS.RRC.SuccConnEstab.WithSI.PsDomain

Number of Successful RRC Connection Setups for PS services (RRC Connection Setup Requests that carried System Information Container Stored Indication)

BSC6900

WRFD-140224


73425021 VS.IU.RanInfoReq.Rx Number of RAN INFORMATION REQUEST Messages Received by RNC from CN

BSC6900

WRFD-140224


73425022 VS.IU.RanInfo.Tx Number of RAN INFORMATION Messages Sent by RNC to CN

BSC6900

WRFD-140224


../RNCCounterHtml/mbsc/m-perf/Mt-14697.html../RNCCounterHtml/mbsc/m-perf/Mt-14698.html../RNCCounterHtml/mbsc/m-perf/Mt-14699.html../RNCCounterHtml/mbsc/m-perf/Mt-14700.html../RNCCounterHtml/mbsc/m-perf/Mt-14701.html../RNCCounterHtml/mbsc/m-perf/Mt-14702.html

WCDMA RAN

Fast CS Fallback Based on RIM 9 Glossary



9-1

9 Glossary

For the acronyms, abbreviations, terms, and definitions, see the Glossary.

Glossary.htm

WCDMA RAN

Fast CS Fallback Based on RIM 10 Reference Documents



10-1

10 Reference Documents

[1] 3GPP TS 23.272

[2] 3GPP TS 23.401

[3] 3GPP TS 25.331

[4] 3GPP TS 25.413

[5] 3GPP TS 36.331

[6] 3GPP TS 48.018

[7] CSFB Feature Parameter Description for eRAN

[8] License Management Feature Parameter Description

License%20Management.htm

1 Introduction1.1 Scope1.2 Intended Audience1.3 Change HistoryDocument Issues02 (2012-07-20)01 (2012-04-30)

2 OverviewFigure 2-1 Procedure for Fast CS Fallback Based on RIM1. The eNodeB obtains the system information of the neighboring UMTS cells of the LTE cell by using the RIM procedures.2. When a UE initiates a CS service and CSFB needs to be performed, the eNodeB sends the UE an RRC Connection Release message that contains the frequency, primary scrambling code, and system information of the target UMTS cell.3. Upon receiving the message, the UE sends the target UMTS cell an RRC Connection Request message without reading the cell system information.

3 Technical DescriptionFigure 3-1 Signaling flowchart for Fast CS Fallback Based on RIM1. The eNodeB obtains the system information of the neighboring UMTS cells of the LTE cell.2. The eNodeB delivers the system information of the target UMTS cell to the UE.3. The UE accesses the target UMTS cell by sending an RRC Connection Request message.

4 Related Features4.1 Required Features4.2 Mutually Exclusive Features4.3 Affected Features

5 Impact on the Network5.1 Impact on System Capacity5.2 Impact on Network Performance

6 Engineering Guidelines6.1 When to Use Fast CS Fallback Based on RIM6.2 Deploying Fast CS Fallback Based on RIMPrerequisitesProcedure1. Configure the data on the LTE side, including setting the neighbor relationships between cells.2. For details about how to configure this feature on the LTE side, see the related documents provided by the LTE equipment vendor. If the LTE equipment is provided by Huawei, see the LTE document CS Fallback Parameter Description.3. Run the BSC6900 MML command SET URRCTRLSWITCH (CME single configuration: UMTS Radio Global Configuration Express > Process Switch Configuration > Process Switch; CME batch modification center: Modifying RNC Parameters in Batches). In this step, sel...1. Trace the Iu-interface and UE signaling on the RNC LMT. Trace the S1 interface signaling (on the eNodeB LMT for Huawei eNodeBs) and the UE signaling (on the M2000 for Huawei eNodeBs).2. Verify that the Direct Information Transfer message that contains RAN-INFORMATION PDU REQUEST or RAN-INFORMATION PDU REPORT is transmitted over the Iu and S1 interfaces.3. Initiate a CS service in an LTE cell. Check the UE signaling and verify that the IE CellInfoListUTRA-FDD-r9 in the RRC Connection Release message contains the frequency, primary scrambling code, and system information (including MIB, SIB1, SIB3, SI...4. Check the UE log and measure the duration between the UE receiving an RRC Connection Release from the eNodeB and the UE sending an RRC Connection Request to the target UMTS cell. Verify that during this duration the UE does not read the system info...5. Check the UE signaling and verify that the RNC sends the UE an RRC_RB_SETUP message that contains the IE rrc-StateIndicator and instructs the UE to move to the CELL_DCH state.1. Run the BSC6900 MML command SET URRCTRLSWITCH (CME single configuration: UMTS Radio Global Configuration Express > Process Switch Configuration > Process Switch; CME batch modification center: Modifying RNC Parameters in Batches). In this step, cle...

Example

6.3 Performance OptimizationMonitoringParameter Optimization

6.4 Troubleshooting

7 ParametersTable 7-1 Parameter description

8 CountersTable 8-1 Counter description

9 Glossary10 Reference Documents[1] 3GPP TS 23.272[2] 3GPP TS 23.401[3] 3GPP TS 25.331[4] 3GPP TS 25.413[5] 3GPP TS 36.331[6] 3GPP TS 48.018[7] CSFB Feature Parameter Description for eRAN[8] License Management Feature Parameter Description

Fast CS Fallback Based on RIM(RAN14.0_02)

Documents

Transcript of Fast CS Fallback Based on RIM(RAN14.0_02)