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PS Handover GBSS14.0
Feature Parameter Description
Issue 01
Date 2012-04-28
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
written consent of Huawei Technologies Co., Ltd.
Trademarks and Permissions
and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.
All other trademarks and trade names mentioned in this document are the property of their respective
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
within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements,
information, and recommendations in this document are provided "AS IS" without warranties, guarantees or
representations of any kind, either express or implied.
The information in this document is subject to change without notice. Every effort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations in this document do not constitute the warranty of any kind, express or implied.
Huawei Technologies Co., Ltd.
Address: Huawei Industrial Base
Bantian, Longgang
Shenzhen 518129
People's Republic of China
Website: http://www.huawei.com
Email: [email protected]
GSM BSS
PS Handover Contents
Issue 01 (2012-04-28) 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
3.1 Handover Algorithm ....................................................................................................................... 3-1
3.2 Intra-BSC Inter-Cell Handover ...................................................................................................... 3-1
3.3 Inter-BSC Inter-Cell Handover ...................................................................................................... 3-5
3.4 Inter-RAT Handover Between the GERAN and the UTRAN ......................................................... 3-5
3.5 Inter-RAT Handover Between the GERAN and the EUTRAN ...................................................... 3-6
4 Parameters.................................................................................................................................. 4-1
5 Counters ...................................................................................................................................... 5-1
6 Glossary ...................................................................................................................................... 6-1
7 Reference Documents ............................................................................................................. 7-1
GSM BSS
PS Handover 1 Introduction
Issue 01 (2012-04-28) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
1-1
1 Introduction
1.1 Scope
This document describes the procedures for intra-BSC inter-cell handover, inter-BSC inter-cell handover, inter-RAT handover between GERAN and UTRAN, and inter-RAT handover between GERAN and EUTRAN.
The feature involved is GBFD-119502 PS Handover.
1.2 Intended Audience
It is assumed that users of this document are familiar with GPRS basics and have a working knowledge of GPRS telecommunication.
This document is intended for:
Personnel working on Huawei GPRS products or systems
System operators who need a general understanding of this feature
1.3 Change History
The change history provides information on the changes in different document versions.
There are two types of changes, which are defined as follows:
Feature change
Feature change refers to the change in the PS Handover feature of a specific product version.
Editorial change
Editorial change refers to the change in wording or the addition of the information that was not described in the earlier version.
Document Issues
The document issues are as follows:
01 (2012-04-28)
Draft A (2012-02-15)
01 (2012-04-28)
This is the first release of GBSS 14.0.
Compared with issue draft A (2012-02-15) of GBSS14.0, issue 01 (2012-04-28) of GBSS14.0 has no change.
Draft A (2012-02-15)
This is the draft release of GBSS14.0.
Compared with issue 01 (2011-03-31) of GBSS13.0, issue Draft A (2012-02-15) of GBSS14.0 has no change.
GSM BSS
PS Handover 2 Overview
Issue 01 (2012-04-28) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
2-1
2 Overview
The IP-based services, such as VoIP, PoC, and Gaming, have high requirements for time delay in the case of cell reselection. As there is an ever increasing number of subscribers to the IP-based services, a solution for minimizing time delay is in great demand. To achieve the minimum possible time delay, Huawei introduces the PS Handover feature that can allocate radio resources to the MS in the target cell before the cell reselection is performed. Thus, the delay is shortened to not more than 150 ms. In addition, the PS Handover feature considers factors such as signal level and load of the neighboring cells before cell reselection is performed. This ensures a high success rate of the PS handover and great data throughput in the target cell, thus improving the QoS.
A PS handover is triggered by the PACKET CELL CHANGE NOTIFICATION message sent from the MS or by the PS handover algorithm. If the triggering conditions of the PS handover are not met, cell reselection is performed. After reselecting the target cell, the MS initiates a cell update procedure. If the triggering conditions of the PS handover are met, a PS handover is performed. In this case, radio resources are allocated in the target cell before the MS initiates a cell update procedure in the source cell. In this manner, the delay caused by the cell update is significantly shortened.
Currently, DTM handover is not supported. In DTM, the BSC makes handover decisions according to CS services. For details, see Handover Feature Parameter Description. CS handovers may disrupt PS services.
According to the locations of the source cell and target cell, PS handover can be classified into:
Intra-BSC inter-cell handover
The source cell and the target cell belong to the same BSC. With regard to whether the BSC exchanges information with the SGSN during the handover process, the intra-BSC inter-cell handover is classified into optimized intra-BSC inter-cell handover and common intra-BSC inter-cell handover.
− Optimized intra-BSC inter-cell handover: The BSC does not exchange information with the SGSN during the handover process.
− Common intra-BSC inter-cell handover: The BSC exchanges information with the SGSN during the handover process.
Currently, only common intra-BSC inter-cell handovers are supported. Therefore, the intra-BSC inter-cell handover described in this document refers to the common intra-BSC inter-cell handover. For details about the optimized intra-BSC inter-cell handover, see 3GPP TS 43.129 "Packet-switched handover for GERAN A/Gb mode; Stage 2."
Inter-BSC inter-cell handover
The source cell and the target cell belong to different BSCs.
Inter-RAT handover between the GERAN and the UTRAN
The source cell and the target cell use different RATs: GERAN and UTRAN. If the source cell is a GERAN cell, then the target cell is a UTRAN cell, and vice versa.
Inter-RAT handover between the GERAN and the EUTRAN
The source cell and the target cell use different RATs: GERAN and EUTRAN. If the source cell is a GERAN cell, then the target cell is an EUTRAN cell, and vice versa. Inter-RAT handover between the GERAN and the EUTRAN includes blind handover. In a blind handover, the target LTE cell is determined by the GERAN configuration. One GSM cell can be configured with only one LTE cell for blind handover.
GSM BSS
PS Handover 3 Technical Description
Issue 01 (2012-04-28) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
3-1
3 Technical Description
3.1 Handover Algorithm
When NCO is set to NC0 or NC1 and the handover is an NACC-based handover, NACCSPT needs to be set to YES.
When NCO is set to NC2, the handover may be a service-based handover, quality-based handover, load-based handover, coverage-based handover, priority-based handover, or blind handover. Blind handover is a special type of inter-RAT handover from the GERAN to the EUTRAN. The target LTE cell for blind handover is determined by the GERAN configuration. That is, no algorithm is required to select the target LTE cell.
If the PDU (DL-UNITDATA PDU, CREATE-BSS-PFC PDU, or PS-HANDOVER-REQUEST PDU) sent from the SGSN to the BSS indicates a suitable RAT for the current service, the MS performs a service-based PS handover. Otherwise, the MS performs a quality-based, load-based, or coverage-based PS handover. The target cell is the neighboring cell with the highest neighboring cell priority. The priority of a neighboring cell is determined by the setting of NCELLPRI(for GERAN neighboring cell), NCELLPRI(for UTRAN neighboring cell), NCELLPRI(for EUTRAN neighboring cell) in neighboring cell relationship. When the parameter is set to an invalid value (255), the priority of the neighboring cell depends on the setting of the parameter for neighboring cells of the same RAT, namely the setting of GERANPRI, UTRANPRI, or EUTRANPRI. For example, if the NCELLPRI for a GERAN neighboring cell is set to an invalid value (255), the priority of the neighboring cell depends on the setting of the parameter for neighboring cells of the same RAT, namely the setting of GERANPRI.
The detailed PS handover schemes are as follows:
If the PDU sent from the SGSN to the BSS indicates that the most suitable RAT for the current service is EUTRAN, then the MS performs a service-based PS handover and the target cell is an EUTRAN cell. If the suitable target cell is not found, then the MS performs a quality-based, load-based, or coverage-based PS handover and the target cell is the GERAN neighboring cell with the highest neighboring cell priority.
If the PDU sent from the SGSN to the BSS indicates that the most suitable RATs for the current service are UTRAN and EUTRAN, then the MS performs a service-based PS handover and the target cell is the neighboring cell with the highest neighboring cell priority. If the suitable target cell is not found, then the MS performs a quality-based, load-based, or coverage-based PS handover.
If the PDU sent from the SGSN to the BSS does not indicate any suitable RAT for the current service, then the MS performs a quality-based, load-based, or coverage-based PS handover and the target cell is the neighboring cell with the highest neighboring cell priority.
The principle of target cell selection in the service-based, quality-based, load-based, and coverage-based handover algorithms is the same as that of target cell selection in the service-based, quality-based, load-based, and coverage-based NC2 cell reselection algorithms respectively. The priority-based handover algorithm selects the target cell according to the settings of NCELLPRI(for GERAN neighboring cell), NCELLPRI(for UTRAN neighboring cell), NCELLPRI(for EUTRAN neighboring cell). For details about the NC2 cell reselection algorithm, see Cell Reselection Algorithms of NC2 Feature Parameter Description.
Each PS handover algorithm involves the following types of handover: intra-BSC inter-cell handover, inter-BSC inter-cell handover, inter-RAT handover between the GERAN and the UTRAN, and inter-RAT handover between the GERAN and the EUTRAN.
3.2 Intra-BSC Inter-Cell Handover
The conditions on which an intra-BSC inter-cell handover decision is based are as follows:
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The MS supports the PS handover.
The radio access capability reported by the MS contains the PS handover field, which specifies whether the MS supports the PS handover.
The BSC supports the PS handover.
− NACCSPT is set to YES, NCO is set to NC0 or NC1, and PSHOSUP is set to YES.
− NC2SPT is set to YES, NCO is set to NC2, and PSHOSUP is set to YES.
The SGSN supports the PS handover.
The Extended Feature Bitmap field is added to the BVC RESET and BVC RESET ACK messages transmitted over the Gb interface between the SGSN and the BSC. This field specifies whether the NSE supports the PS handover.
− If the BVC RESET or BVC RESET ACK message received from the SGSN does not contain the Extended Feature Bitmap field or if the Extended Feature Bitmap field indicates that the PS handover is not supported, it is regarded that none of the cells under the NSE of the SGSN supports the PS handover. That is, the source cell does not support the PS handover.
− Otherwise, all the cells under the NSE of the SGSN support the PS handover, that is, the source cell supports the PS handover.
Through the preceding negotiation procedure, the BSC determines whether the SGSN supports the PS handover.
Both the BSC and the SGSN support the Packet Flow Context (PFC) procedure.
When the conditions on which intra-BSC inter-cell handover decision is based are met, any of the following conditions may trigger an intra-BSC inter-cell handover:
If NCO is set to NC0 or NC1, the PACKET CELL CHANGE NOTIFICATION message sent from the MS to the BSC contains the information about the target cell. If both the source cell and the target cell are GERAN cells, the BSC determines whether the target cell supports PS handover. If the target cell supports PS handover, an intra-BSC inter-cell PS handover is triggered. If the target cell does not support PS handover, intra-BSC inter-cell PS handover is not triggered.
If NCO is set to NC2, the MS sends measurement reports to the BSC, and the BSC obtains the information about the target cell through the PS handover algorithm. If both the source cell and the target cell are GERAN cells, the BSC determines whether the target cell supports PS handover. If the target cell supports PS handover, an intra-BSC inter-cell PS handover is triggered. If the target cell does not support PS handover, an intra-BSC inter-cell PS handover is not triggered.
The information about the target cell can be obtained according to the triggering conditions. It is used in the procedure for the preparation of an intra-BSC inter-cell handover. This procedure prepares radio resources for the handover from the source cell to the target cell.
Handover Preparation
Figure 3-1 shows the procedure for the preparation of a common intra-BSC inter-cell handover.
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Figure 3-1 Procedure for the preparation of a common intra-BSC inter-cell handover
1. The MS in the source cell sends a PS Handover Required message to the SGSN. The message contains the following IEs: old TLLI, handover cause, source cell ID, target cell ID, transparent container (containing the radio access capability of the MS, paging mode, global TFI, whether to request the system information of the target cell) from the source BSC to the target BSC, and active PFC list (containing the PFI of each PFC).
2. After receiving the PS Handover Required message, the SGSN determines the handover type (intra-SGSN handover, inter-SGSN handover, or inter-RAT handover) according to the ID of the target cell and checks whether the routing area is changed. If the routing area remains unchanged, the SGSN sends the target BSC a PS Handover Request message. The message contains the following IEs: TLLI, IMSI, handover cause, source cell identifier, target cell identifier, transparent container from the source cell to the target cell, and PFC list to be created. If the routing area changes, the SGSN allocates a new P-TMSI to the MS and generates a new TLLI based on the P-TMSI before sending a PS Handover Request message to the target cell.
3. After receiving the PS Handover Request message, the target cell creates the MS context and requests the BSC for uplink channel resources. In addition, the target cell obtains its own system information and creates the transparent container from the target BSC to the source BSC.
4. The BSC sends the SGSN a PS Handover Request Acknowledge message. The message contains the following IEs: TLLI, successfully created PFC list, and transparent container (including the PS handover command and the system information of the target cell) from the target cell to the source cell. Then, the BSC prepares to receive downlink LLC PDUs. When the SGSN receives the PS Handover Request Acknowledge message, the resource allocation for the MS in the target cell is complete. At this time, the PS handover preparation phase ends and the PS handover execution phase begins.
Handover Execution
Figure 3-2 shows the procedure for the execution of a common intra-BSC inter-cell handover.
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Figure 3-2 Procedure for the execution of a common intra-BSC inter-cell handover
1. The SGSN sends downlink LLC PDUs to the MS through the source cell.
2. After receiving the PS Handover Request Acknowledge message, the SGSN sends subsequent LLC PDUs to the target cell according to the QoS. The BSC sends downlink data to the MS on the allocated radio channels. At this time, the MS still camps on the source cell.
3. The SGSN sends a PS Handover Required Acknowledge message to the BSC. The message contains the following IEs: TLLI, successfully created PFC list, and transparent container (including the handover command and the system information of the target cell) from the target BSC to the source BSC. Before sending the PS Handover Required Acknowledge message to the BSC, the SGSN can suspend the downlink data transmission of any PDP context according to the QoS.
4. The BSC suspends the downlink data transmission and then sends a PS Handover Command message to the MS. After sending the message, the BSC resumes the downlink data transmission until no LLC PDU needs to be transmitted or the PFC is released. After receiving the PS Handover Command message, the MS stops data reception in the source cell and meanwhile suspends the uplink data transmission. After receiving the PS Handover Command message, the MS processes the uplink data as follows:
− In the case of a PFC with an ongoing handover, all the uplink data packets that are not transmitted are buffered according to the QoS levels.
− Subsequent uplink data packets are buffered according to the QoS levels.
− The MS can discard uplink data packets during the link disruption period to meet the real-time requirements.
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5. On the radio channels allocated in the handover preparation phase, the MS sends the BSC a PS Handover Access message through four access bursts. The message contains the reference information on the handover.
6. Based on the reference information in the PS Handover Access message from the MS, the BSC determines whether to send the MS a Packet Physical information message. If the PS Handover Command message does not contain the TA, the BSC sends a Packet Physical Information message containing the TA to the MS. If the PS Handover Command message contains the TA, the BSC does not send a Packet Physical Information message to the MS.
7. The MS determines whether the routing areas of the source cell and target cell are the same. If they are the same, the MS sends a Cell Update message to the SGSN. If they are different, the MS sends a Routing Area Update Request message to the SGSN.
8. After receiving the first correct uplink data block (common burst sequence), the BSC sends the SGSN a PS Handover Complete (containing the TLLI and IMSI) message, notifying the SGSN that the MS is handed over to the target cell. At the same time, the MS sends data packets.
9. After receiving the PS Handover Complete message, the SGSN instructs the BSC to delete the PFC corresponding to the source cell. After receiving the Delete BSC PFC message from the SGSN, the BSC deletes the PFC corresponding to the source cell, and removes the radio resources such as TBF and channels at the same time. In this case, the BSC receives data from the SGSN and sends data to the MS.
3.3 Inter-BSC Inter-Cell Handover
On the BSC side, an inter-BSC inter-cell handover is the same as an intra-BSC inter-cell handover in the following ways: the conditions on which a handover decision is based, the triggering conditions of a handover, and the procedures for handover preparation and handover execution. However, on the CN side, the procedures for handover preparation and handover execution are different. For details about the procedures on the BSC side, see 3.2 Intra-BSC Inter-Cell Handover. For details about the procedures on the CN side, see 3GPP TS 43.129 “Packet-switched handover for GERAN A/Gb mode; Stage 2.”
3.4 Inter-RAT Handover Between the GERAN and the UTRAN
The inter-RAT handover between the GERAN and the UTRAN involves inter-RAT handover from the GERAN to the UTRAN and inter-RAT handover from the UTRAN to the GERAN. The inter-RAT handover from the GERAN to the UTRAN is a handover in which the mobile terminal is handed over from a GERAN cell to a UTRAN cell, and the inter-RAT handover from the UTRAN to the GERAN is a handover in which the mobile terminal is handed over from a UTRAN cell to a GERAN cell.
The conditions on which an inter-RAT handover decision between the GERAN and the UTRAN is based are as follows:
The MS supports the PS handover.
The radio access capability reported by the MS contains the PS handover field, which specifies whether the MS supports the PS handover.
The BSC supports the PS handover.
NC2SPT is set to YES, NCO is set to NC2, and PSHOSUP is set to YES. In the case of an inter-RAT handover from the GERAN to the UTRAN, SPTINTERRATOUTBSCPSHO is set to YES. In the case of an inter-RAT handover from the UTRAN to the GERAN, SPTINTERRATINBSCPSHO is set to YES.
The SGSN supports the PS handover.
The Extended Feature Bitmap field is added to the BVC RESET and BVC RESET ACK messages transmitted over the Gb interface between the SGSN and the BSC. This field specifies whether the NSE supports the PS handover.
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− If the BVC RESET or BVC RESET ACK message received from the SGSN does not contain the Extended Feature Bitmap field or if the Extended Feature Bitmap field indicates that the PS handover is not supported, it is regarded that none of the cells under the NSE of the SGSN supports the PS handover. That is, the source cell does not support the PS handover.
− Otherwise, all the cells under the NSE of the SGSN support the PS handover, that is, the source cell supports the PS handover.
Through the preceding negotiation procedure, the BSC determines whether the SGSN supports the PS handover.
The BSC and the SGSN support the PFC procedure.
Inter-RAT Handover from the GERAN to the UTRAN
An inter-RAT handover from the GERAN to the UTRAN is triggered in any of the following conditions:
When NCO is set to NC0 or NC1, the PACKET CELL CHANGE NOTIFICATION message sent from the MS to the BSC contains the information about the target cell. If the target cell is a UTRAN cell and SPTINTERRATOUTBSCPSHO is set to YES, an inter-RAT handover from the GERAN to the UTRAN is triggered. Otherwise, an inter-RAT handover from the GERAN to the UTRAN is not triggered.
When NCO is set to NC2, the MS sends measurement reports to the BSC, and the BSC obtains the information about the target cell through the PS handover algorithm. If the target cell is a UTRAN cell and SPTINTERRATOUTBSCPSHO is set to YES, an inter-RAT handover from the GERAN to the UTRAN is triggered. Otherwise, an inter-RAT handover from the GERAN to the UTRAN is not triggered.
The information about the target cell can be obtained according to the triggering conditions.
On the BSC side, the preparation procedure and execution procedure for an inter-RAT handover from the GERAN to the UTRAN are almost the same as those for an intra-BSC inter-cell handover. The difference is as follows:
The target cell is a UTRAN cell.
The PS Handover Required message carries the transparent container from the source BSC to the target RNC (containing the information about the radio access capability of the MS, paging mode, global TFI, and whether to request the system information of the target cell).
The PS Handover Required Acknowledge carries the transparent container from the source RNC to the target BSC (containing the handover command and the system information of the target cell).
Inter-RAT Handover from the UTRAN to the GERAN
The time for triggering an inter-RAT handover from the UTRAN to the GERAN is determined by the UTRAN. The PS Handover Required message sent from the RNC to the BSC carries the information about the target cell. On the BSC side, the preparation procedure and execution procedure for an inter-RAT handover from the UTRAN to the GERAN are almost the same as those for an intra-BSC inter-cell handover.
3.5 Inter-RAT Handover Between the GERAN and the EUTRAN
The inter-RAT handover between the GERAN and the EUTRAN involves inter-RAT handover from the GERAN to the EUTRAN and inter-RAT handover from the EUTRAN to the GERAN. The inter-RAT handover from the GERAN to the EUTRAN is a handover in which the mobile terminal is handed over from a GERAN cell to an EUTRAN cell, and the inter-RAT handover from the EUTRAN to the GERAN is a handover in which the mobile terminal is handed over from an EUTRAN cell to a GERAN cell.
The triggering conditions of an inter-RAT handover between the GERAN and the EUTRAN are as follows:
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The MS supports the PS handover.
The radio access capability reported by the MS contains the PS handover field, which specifies whether the MS supports the PS handover.
The BSC supports the PS handover.
NC2SPT is set to YES, NCO is set to NC2, and PSHOSUP is set to YES. In the case of an inter-RAT handover from the GERAN to the EUTRAN, SPTLTEOUTBSCPSHO is set to YES. In the case of an inter-RAT handover from the EUTRAN to the GERAN, SPTLTEINBSCPSHO is set to YES.
In the case of an inter-RAT blind handover from the GERAN to the EUTRAN, NACCSPT is set to NO, NCO is set to NC0, PSHOSUP is set to YES, SPTBLINDHO is set to YES, and SPTLTEINBSCPSHO is set to YES.
The SGSN supports the PS handover.
The Extended Feature Bitmap field is added to the BVC RESET and BVC RESET ACK messages transmitted over the Gb interface between the SGSN and the BSC. This field specifies whether the NSE supports the PS handover.
− If the BVC RESET or BVC RESET ACK message received from the SGSN does not contain the Extended Feature Bitmap field or if the Extended Feature Bitmap field indicates that the PS handover is not supported, it is regarded that none of the cells under the NSE of the SGSN supports the PS handover. That is, the source cell does not support the PS handover.
− Otherwise, all the cells under the NSE of the SGSN support the PS handover, that is, the source cell supports the PS handover.
Through the preceding negotiation procedure, the BSC determines whether the SGSN supports the PS handover.
The BSC and the SGSN support the PFC procedure.
Inter-RAT Handover from the GERAN to the EUTRAN
Inter-RAT handover from the GERAN to the EUTRAN involves NACC-based handover, service-based handover, quality-based handover, load-based handover, coverage-based handover, priority-based handover, and blind handover.
An inter-RAT NACC-based handover from the GERAN to the EUTRAN is triggered when all the following conditions are met: The PACKET CELL CHANGE NOTIFICATION message sent from the MS to the MSC contains the information about the target cell; the target cell is an EUTRAN cell, and the source cell is a GERAN cell; SPTLTEOUTBSCPSHO is set to YES. Otherwise, an inter-RAT handover from the GERAN to the EUTRAN is not triggered. The information about the target cell can be obtained according to the triggering conditions.
An inter-RAT service-based, quality-based, load-based, coverage-based, or priority-based handover from the GERAN to the EUTRAN is triggered when all the following conditions are met: The MS sends measurement reports to the BSC; the BSC obtains the information about the target cell of PS handover through the handover algorithm; the target cell is an EUTRAN cell, and the source cell is a GERAN cell; SPTLTEOUTBSCPSHO is set to YES. Otherwise, an inter-RAT handover from the GERAN to the EUTRAN is not triggered. The information about the target cell can be obtained according to the triggering conditions.
An inter-RAT blind handover from the GERAN to the EUTRAN is triggered when any of the following conditions is met:
The DL-UNITDATA, CREATE-BSS-PFC, or PS-HANDOVER-REQUEST message carries the Service UTRAN CCO IE, the value of the Service UTRAN CCO Value part is not 000, and the value of the Service E-UTRAN CCO Value part is 01.
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The channel multiplexing rate of the GERAN cell is higher than LOADRESELSTARTTHRSH, NCELLPRI for EUTRAN neighboring cells is the highest in neighboring cell relationship, and the value of the Service E-UTRAN CCO Value part is 01.
The information about the target cell can be obtained according to the triggering conditions. Blind handover occurs only in the scenario where a GERAN cell and an EUTRAN cell are co-cited and provide the same coverage.
On the BSC side, the preparation procedure and execution procedure for an inter-RAT handover from the GERAN to the EUTRAN are almost the same as those for an intra-BSC inter-cell handover. The differences are as follows:
The target cell is an EUTRAN cell.
The PS Handover Required message carries the transparent container from the source BSC to the target eNodeB (containing the radio access capability of the MS, paging mode, global TFI, and whether to request the system information of the target cell).
The PS Handover Required Acknowledge carries the transparent container from the source BSC to the target eNodeB (containing the handover command and the system information of the target cell).
Inter-RAT Handover from the EUTRAN to the GERAN
The time for triggering an inter-RAT handover from the EUTRAN to the GERAN is determined by the EUTRAN. The PS Handover Required message sent from the eNodeB to the BSS carries the information about the target cell.
On the BSC side, the preparation procedure and execution procedure for an inter-RAT handover from the EUTRAN to the GERAN are almost the same as those for an intra-BSC inter-cell handover. The differences are as follows:
During an inter-RAT handover from the EUTRAN to the GERAN, the PS Handover Request message does not carry the ID of the source BSC cell or the ID of the source EUTRAN cell.
The PS Handover Request message carries the transparent container from the source eNodeB to the target BSS. The information contained in this container is determined by the EUTRAN and is not described in this document.
GSM BSS
PS Handover 4 Parameters
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4 Parameters
Table 4-1 Parameter description
Parameter ID NE MML Command Description
EUTRANPRI BSC6900 SET GCELLPRIEUTRANSYS
Meaning: Common priority of EUTRAN. Value 0 indicates the lowest priority, and value 7 indicates the highest priority.
GUI Value Range: 0~7
Actual Value Range: 0~7
Default Value: 0
Unit: None
GERANPRI BSC6900 SET GCELLPRIEUTRANSYS
Meaning: Common priority of GERAN. Value 0 indicates the lowest priority, and value 7 indicates the highest priority.
GUI Value Range: 0~7
Actual Value Range: 0~7
Default Value: 7
Unit: None
LOADRESELSTARTTHRSH BSC6900 SET GCELLNC2PARA Meaning: When the uplink load or downlink load of the cell exceeds this threshold, the load reselection decision is made.
GUI Value Range: 0~100
Actual Value Range: 0~100
Default Value: 85
Unit: %
NACCSPT BSC6900 SET GCELLGPRS Meaning: Whether to support Network Assisted Cell Change (NACC). NACC is used in the network control mode NC0, NC1 or NC2. When an MS is in packet transfer mode, the NACC enables the network to notify the MS in advance of the system information about neighboring cells, accelerating cell reselection for MSs.
GUI Value Range: NO(No), YES(Yes)
Actual Value Range: NO, YES
Default Value: NO(No)
Unit: None
GSM BSS
PS Handover 4 Parameters
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Parameter ID NE MML Command Description
NC2SPT BSC6900 SET GCELLGPRS Meaning: Whether to support network control 2 (NC2). In NC2 mode, an MS sends the BSC measurement reports containing information about the serving cell and neighboring cells, and the network controls cell reselection for the MS.
GUI Value Range: NO(No), YES(Yes)
Actual Value Range: NO, YES
Default Value: NO(No)
Unit: None
NCELLPRI BSC6900 ADD G3GNCELL
MOD G3GNCELL
Meaning: Common priority of the neighboring 3G cell. Value 0 indicates the lowest priority, and value 7 indicates the highest priority. Value 255 is invalid.
GUI Value Range: 0~7;255
Actual Value Range: 0~7, 255
Default Value: 255
Unit: None
NCELLPRI BSC6900 ADD GLTENCELL
MOD GLTENCELL
Meaning: Common priority of the neighboring LTE cell. Value 0 indicates the lowest priority, and value 7 indicates the highest priority. Value 255 is invalid.
GUI Value Range: 0~7;255
Actual Value Range: 0~7, 255
Default Value: 255
Unit: None
NCELLPRI BSC6900 ADD G2GNCELL
MOD G2GNCELL
Meaning: Common priority of the neighboring 2G cell. Value 0 indicates the lowest priority, and value 7 indicates the highest priority. Value 255 is invalid.
GUI Value Range: 0~7;255
Actual Value Range: 0~7, 255
Default Value: 255
Unit: None
GSM BSS
PS Handover 4 Parameters
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Parameter ID NE MML Command Description
NCO BSC6900 SET GCELLPSBASE Meaning: Network control mode for cell reselection of the MS. There are three modes. NC0: normal MS control. The MS shall perform autonomous cell re-selection. NC1: MS control with measurement reports. The MS shall send measurement reports to the network and the MS shall perform autonomous cell re-selection. NC2: network control. The MS shall send measurement reports to the network. The MS shall only perform autonomous cell re-selection when the reselection is triggered by a downlink signaling failure or a random access failure. When this parameter is set to NC2 and "Support NC2" in "SET GCELLGPRS" is set to "YES", the network side can control the cell reselection for the MS.
GUI Value Range: NC0(NC0), NC1(NC1), NC2(NC2)
Actual Value Range: NC0, NC1, NC2
Default Value: NC0(NC0)
Unit: None
PSHOSUP BSC6900 ADD NSE
MOD NSE
Meaning: Whether to support PS Handover(PS HO). The PS HO is used to reduce the interval of the cell reselection of the MS.
GUI Value Range: NO(No Support), YES(Support)
Actual Value Range: NO, YES
Default Value: NO(No Support)
Unit: None
SPTBLINDHO BSC6900 ADD GLTENCELL
MOD GLTENCELL
Meaning: Whether to support the blind handover from the source GSM cell to the target LTE cell. The blind handover from the source GSM cell to the target LTE cell indicates that the MS in the GSM cell is
GSM BSS
PS Handover 4 Parameters
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Parameter ID NE MML Command Description
handed over to the target LTE cell without measuring the target LTE cell.
GUI Value Range: UNSUPPORT(UNSUPPORT), SUPPORT(SUPPORT)
Actual Value Range: UNSUPPORT, SUPPORT
Default Value: UNSUPPORT(UNSUPPORT)
Unit: None
SPTINTERRATINBSCPSHO BSC6900 SET GCELLGPRS Meaning: Whether to support In Inter-RAT Inter-cell PS Handover. The MS in the UMTS cell can be handed over to the BSC local cell through PS handover algorithm.
GUI Value Range: UNSUPPORT(Not Support), SUPPORT(Support)
Actual Value Range: UNSUPPORT, SUPPORT
Default Value: UNSUPPORT(Not Support)
Unit: None
SPTINTERRATOUTBSCPSHO
BSC6900 SET GCELLGPRS Meaning: Whether support Out Inter-RAT Inter-Cell PS Handover. The MS in the BSC local cell can be handed over to the UMTS cell through PS handover algorithm.
GUI Value Range: UNSUPPORT(Not Support), SUPPORT(Support)
Actual Value Range: UNSUPPORT, SUPPORT
Default Value: UNSUPPORT(Not Support)
Unit: None
SPTLTEINBSCPSHO BSC6900 SET GCELLGPRS Meaning: Whether to allow a PS handover from an LTE cell to a GSM cell
GUI Value Range: UNSUPPORT(Not Support), SUPPORT(Support)
GSM BSS
PS Handover 4 Parameters
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Parameter ID NE MML Command Description
Actual Value Range: UNSUPPORT, SUPPORT
Default Value: UNSUPPORT(Not Support)
Unit: None
SPTLTEOUTBSCPSHO BSC6900 SET GCELLGPRS Meaning: Whether to allow a PS handover from a GSM cell to an LTE cell.
GUI Value Range: UNSUPPORT(Not Support), SUPPORT(Support)
Actual Value Range: UNSUPPORT, SUPPORT
Default Value: UNSUPPORT(Not Support)
Unit: None
UTRANPRI BSC6900 SET GCELLPRIEUTRANSYS
Meaning: Common priority of UTRAN. Value 0 indicates the lowest priority, and value 7 indicates the highest priority.
GUI Value Range: 0~7
Actual Value Range: 0~7
Default Value: 1
Unit: None
GSM BSS
PS Handover 5 Counters
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5 Counters
Table 5-1 Counter description
Counter ID Counter Name Counter Description Feature ID
1279187422 EXTENDED.RLCMAC.CONTROL.MESSAGE.SEGMENTATION.CAPABILITY
A9706:Processing Times of PS Services by MSs Supporting Extended RLC/MAC Control Message Segmentation
GBFD-119502
1279187423 PS.HANDOVER.CAPABILITY A9707:Processing Times of PS Services by MSs Supporting PS Handover
GBFD-119502
1282429593 CELL.INTRA2G.INCELL.PSHO.REQ
H9201:Number of Incoming Inter-Cell PS Handover Requests Within 2G
GBFD-119502
1282429603 CELL.2G3GINTERRAN.INCELL.PSHO.REQ
H9601:Number of Incoming Inter-RAT Inter-Cell PS Handover Requests Between 2G and 3G
GBFD-119502
1282429608 CELL.2G4GINTERRAN.INCELL.PSHO.REQ
H9602:Number of Incoming Inter-RAT Inter-Cell PS Handover Requests Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
1282429793 CELL.INTRA2G.INCELL.PSHO.FAIL
H9221:Number of Failed Incoming Inter-Cell PS Handovers Within 2G
GBFD-119502
1282429795 CELL.2G3GINTERRAN.INCELL.PSHO.FAIL
H9621:Number of Failed Incoming Inter-RAT Inter-Cell PS Handovers Between 2G and 3G
GBFD-119502
1282429796 CELL.2G4GINTERRAN.INCELL.PSHO.FAIL
H9622:Number of Failed Incoming Inter-RAT Inter-Cell PS Handovers Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
1282429797 NC.CELL.TRAFFIC.RESELECT.ATMPT
H9020:Number of Network-Controlled Cell Reselection Attempts Due to Service Type
GBFD-119502
1282429798 CELL.OUTCELL.URG.PSHO.ATMPT
H9711:Number of Outgoing Inter-Cell PS Handover Attempts Due to Downlink Quality
GBFD-119502
1282429799 CELL.OUTCELL.PSHO.ATMPT H9712:Number of Outgoing Inter-Cell PS Handover Attempts
GBFD-119502
GSM BSS
PS Handover 5 Counters
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Counter ID Counter Name Counter Description Feature ID
1282429800 CELL.OUTCELL.TRAFFIC.PSHO.ATMPT
H9713:Number of Outgoing Inter-Cell PS Handover Attempts Due to Service Type
GBFD-119502
1282429801 CELL.OUTCELL.LOAD.PSHO.ATMPT
H9714:Number of Outgoing Inter-Cell PS Handover Attempts Due to Traffic Load
GBFD-119502
1282429802 CELL.OUTCELL.GENERAL.PSHO.ATMPT
H9715:Number of Outgoing Inter-Cell PS Handover Attempts for Better Cell
GBFD-119502
1282429803 CELL.OUTCELL.PSHO.FAIL H9723:Number of Failed Outgoing Inter-Cell PS Handovers
GBFD-119502
1282429804 CELL.INTRA2G.OUTCELL.PSHO.ATMPT
H9716:Number of Outgoing Inter-Cell PS Handover Attempts Within 2G
GBFD-119502
1282429806 CELL.INTERRAN.OUTCELL.PSHO.ATMPT
H9511:Number of Outgoing Inter-RAT Inter-Cell PS Handover Attempts
GBFD-119502
1282429807 CELL.2G3GINTERRAN.OUTCELL.PSHO.ATMPT
H9512:Number of Outgoing Inter-RAT Inter-Cell PS Handover Attempts Between 2G and 3G
GBFD-119502
1282429808 CELL.2G3GINTERRAN.OUTCELL.PSHO.FAIL
H9521:Number of Failed Outgoing Inter-RAT Inter-Cell PS Handovers Between 2G and 3G
GBFD-119502
1282429809 CELL.2G4GINTERRAN.OUTCELL.PSHO.ATMPT
H9513:Number of Outgoing Inter-RAT Inter-Cell PS Handover Attempts Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
1282429810 CELL.2G4GINTERRAN.OUTCELL.PSHO.FAIL
H9522:Number of Failed Outgoing Inter-RAT Inter-Cell PS Handovers Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
1282429813 CELL.INTRA2G.OUTCELL.PSHO.FAIL
H9722:Number of Failed Outgoing Inter-Cell PS Handovers Within 2G
GBFD-119502
1282431639 CELL.INTRA2G.INCELL.PSHO.ACK
H9211:Number of Responses to Incoming Inter-Cell PS Handover Requests Within 2G
GBFD-119502
1282431640 CELL.2G3GINTERRAN.INCELL.PSHO.ACK
H9611:Number of Responses to Incoming Inter-RAT Inter-Cell PS Handover Requests Between 2G and 3G
GBFD-119502
GSM BSS
PS Handover 5 Counters
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5-3
Counter ID Counter Name Counter Description Feature ID
1282431641 CELL.2G4GINTERRAN.INCELL.PSHO.ACK
H9612:Number of Responses to Incoming Inter-RAT Inter-Cell PS Handover Requests Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
1282431642 CELL.INTRA2G.OUTCELL.PSHO.CMD
H9706:Number of Outgoing Inter-Cell PS Handover Commands Within 2G
GBFD-119502
1282431643 CELL.2G3GINTERRAN.OUTCELL.PSHO.CMD
H9502:Number of Outgoing Inter-RAT Inter-Cell PS Handover Commands Between 2G and 3G
GBFD-119502
1282431644 CELL.2G4GINTERRAN.OUTCELL.PSHO.CMD
H9503:Number of Outgoing Inter-RAT Inter-Cell PS Handover Commands Between 2G and 4G
GBFD-119502
GBFD-511302
GBFD-511303
GBFD-511304
GBFD-511305
GBFD-511306
GSM BSS
PS Handover 6 Glossary
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6 Glossary
For the acronyms, abbreviations, terms, and definitions, see the Glossary.
GSM BSS
PS Handover 7 Reference Documents
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7 Reference Documents
[1] 3GPP TS 43.129: “Packet-switched handover for GERAN A/Gb mode; Stage 2”
[2] 3GPP TS 48.018: “BSC GPRS Protocol (BSCGP)”
[3] 3GPP TS 44.060: “Radio Link Control/Medium Access Control (RLC/MAC) protocol”
[4] BSC6900 Feature List
[5] BSC6900 Optional Feature Description
[6] BSC6900 GSM Parameter Reference
[7] BSC6900 GSM MML Command Reference
[8] BSC6900 Performance Counter Reference
[9] NACC Feature Parameter Description
[10] NC2 Feature Parameter Description