GBSS14.0
GBSS Capacity Monitoring Guide
Issue
02
Date
2013-04-15
HUAWEI TECHNOLOGIES CO., LTD.
Copyright © Huawei Technologies Co., Ltd. 2013. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior written
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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
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Huawei Technologies Co., Ltd.
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About This Document
About This Document
Overview
This document provides guidelines for GBSS capacity monitoring and provides methods for
diagnosing network capacity problems. It helps maintenance engineers and network
optimization engineers monitor the usage of network resources in a timely manner, provides
data basis for adjusting, optimizing, and expanding network capacity, and prevents deterioration
in network quality and user experience due to insufficient network capacity.
Product Version
The following table lists the product versions related to this document.
Product Name
Product Version
BSC6900
V900R014C00
BTS3900/BTS3900A/BTS3900L/BTS3900AL/DBS3900
V100R014C00
Intended Audience
This document is intended for:
l
Maintenance engineers
l
Network optimization engineers
Organization
1 Change in the GBSS Capacity Monitoring Guide
The section provides information about the changes in different document versions of GBSS
Capacity Monitoring Guide.
2 System Capacity Data Collection
This section describes how to collect, monitor, and analyze measurement results of performance
counters related to GBSS capacity on the M2000 client.
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About This Document
3 Capacity Counter Categories and Capacity Problem Locating Methods
This chapter describes key performance counters related to all capacity resources and provides
the methods for identifying and troubleshooting resource bottleneck.
4 Radio Resource Monitoring
Monitoring radio resources involves monitoring the loads of PCHs, SDCCHs, TCHs, and
PDCHs.
5 Equipment Resource Monitoring
Monitoring equipment resources involves monitoring the loads of XPU boards, DPUa/DPUc/
DPUf boards, DPUd/DPUg boards, interface boards, and inter-subrack BSC communication
resources.
6 Transmission Resource Monitoring
Monitoring transmission resources involves monitoring the loads of A, Ater, Gb, and Abis
interface transmission resources.
Conventions
Symbol Conventions
The symbols that may be found in this document are defined as follows.
Symbol
Description
Indicates a hazard with a high level or medium level of risk
which, if not avoided, could result in death or serious injury.
Indicates a hazard with a low level of risk which, if not
avoided, could result in minor or moderate injury.
Indicates a potentially hazardous situation that, if not
avoided, could result in equipment damage, data loss,
performance deterioration, or unanticipated results.
Indicates a tip that may help you solve a problem or save
time.
Provides additional information to emphasize or supplement
important points of the main text.
General Conventions
The general conventions that may be found in this document are defined as follows.
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Convention
Description
Times New Roman
Normal paragraphs are in Times New Roman.
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Convention
Description
Boldface
Names of files, directories, folders, and users are in
boldface. For example, log in as user root.
Italic
Book titles are in italics.
Courier New
Examples of information displayed on the screen are in
Courier New.
Command Conventions
The command conventions that may be found in this document are defined as follows.
Convention
Description
Boldface
The keywords of a command line are in boldface.
Italic
Command arguments are in italics.
[]
Items (keywords or arguments) in brackets [ ] are optional.
{ x | y | ... }
Optional items are grouped in braces and separated by
vertical bars. One item is selected.
[ x | y | ... ]
Optional items are grouped in brackets and separated by
vertical bars. One item is selected or no item is selected.
{ x | y | ... }*
Optional items are grouped in braces and separated by
vertical bars. A minimum of one item or a maximum of all
items can be selected.
[ x | y | ... ]*
Optional items are grouped in brackets and separated by
vertical bars. Several items or no item can be selected.
GUI Conventions
The GUI conventions that may be found in this document are defined as follows.
Convention
Description
Boldface
Buttons, menus, parameters, tabs, window, and dialog titles
are in boldface. For example, click OK.
>
Multi-level menus are in boldface and separated by the ">"
signs. For example, choose File > Create > Folder.
Keyboard Operations
The keyboard operations that may be found in this document are defined as follows.
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Format
Description
Key
Press the key. For example, press Enter and press Tab.
Key 1+Key 2
Press the keys concurrently. For example, pressing Ctrl+Alt
+A means the three keys should be pressed concurrently.
Key 1, Key 2
Press the keys in turn. For example, pressing Alt, A means
the two keys should be pressed in turn.
Mouse Operations
The mouse operations that may be found in this document are defined as follows.
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Action
Description
Click
Select and release the primary mouse button without moving
the pointer.
Double-click
Press the primary mouse button twice continuously and
quickly without moving the pointer.
Drag
Press and hold the primary mouse button and move the
pointer to a certain position.
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Contents
Contents
About This Document.....................................................................................................................ii
1 Change in the GBSS Capacity Monitoring Guide..................................................................1
2 System Capacity Data Collection...............................................................................................3
3 Capacity Counter Categories and Capacity Problem Locating Methods...........................4
3.1 Capacity Counter Categories..............................................................................................................................5
3.2 Capacity Monitoring and Problem Locating Methods.......................................................................................8
3.2.1 Methods for Locating Capacity Problems.................................................................................................8
3.2.2 Methods for Troubleshooting Capacity Problems.....................................................................................9
4 Radio Resource Monitoring......................................................................................................12
4.1 PCH Load.........................................................................................................................................................13
4.2 SDCCH Load....................................................................................................................................................14
4.3 TCH Load.........................................................................................................................................................15
4.4 PDCH Load......................................................................................................................................................15
5 Equipment Resource Monitoring.............................................................................................17
5.1 XPU CPU Usage..............................................................................................................................................18
5.2 DPU (CS) Load................................................................................................................................................18
5.3 DPU (PS) Load.................................................................................................................................................19
5.4 Interface Board Load........................................................................................................................................20
5.5 Inter-Subrack BSC Communication Bandwidth and Load..............................................................................21
6 Transmission Resource Monitoring........................................................................................23
6.1 A Interface (Signaling).....................................................................................................................................24
6.1.1 A over TDM (Signaling).........................................................................................................................24
6.1.2 A over IP (Signaling)...............................................................................................................................25
6.2 A Interface (Traffic).........................................................................................................................................26
6.2.1 A over TDM (Traffic)..............................................................................................................................26
6.2.2 A over IP (Traffic)...................................................................................................................................26
6.3 Ater Interface....................................................................................................................................................27
6.4 Gb Interface......................................................................................................................................................28
6.4.1 Gb over FR..............................................................................................................................................28
6.4.2 Gb over IP................................................................................................................................................29
6.5 Abis Interface...................................................................................................................................................30
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6.5.1 Abis over TDM .......................................................................................................................................30
6.5.2 Abis over IP.............................................................................................................................................31
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1 Change in the GBSS Capacity Monitoring Guide
Change in the GBSS Capacity Monitoring
Guide
The section provides information about the changes in different document versions of GBSS
Capacity Monitoring Guide.
02 (2013-04-15)
This is the second commercial release of GBSS14.0.
Compared with issue 01 (2012-08-30) of GBSS14.0, this issue includes the following new topics:
l
3.2 Capacity Monitoring and Problem Locating Methods
Compared with issue 01 (2012-08-30) of GBSS14.0, this issue includes the following
incorporate changes:
Content
Description
6.2.2 A over IP (Traffic)
Optimized transmission resource monitoring
methods.
6.5.2 Abis over IP
3 Capacity Counter Categories and
Capacity Problem Locating Methods
Issue 02 (2013-04-15)
Changed the name of this chapter from
Capacity Counter Categories and
Capacity Expansion Specifications to
Capacity Counter Categories and
Capacity Problem Locating Methods.
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Content
Description
4.2 SDCCH Load
Added the description about monitoring
principles in the Related Counters.
4.3 TCH Load
4.4 PDCH Load
5.1 XPU CPU Usage
5.2 DPU (CS) Load
5.3 DPU (PS) Load
5.4 Interface Board Load
5.5 Inter-Subrack BSC Communication
Bandwidth and Load
6.2.1 A over TDM (Traffic)
Compared with issue 01 (2012-08-30) of GBSS14.0, this issue excludes the following new
topics:
l
Capacity Monitoring and Problem Location Methods
01 (2012-08-30)
This is the first commercial release of GBSS14.0.
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2 System Capacity Data Collection
System Capacity Data Collection
This section describes how to collect, monitor, and analyze measurement results of performance
counters related to GBSS capacity on the M2000 client.
Prerequisites
l
You have logged in to the M2000 client. The M2000 client communicates with NEs
properly.
l
You have been granted the performance management permission.
Context
For the ease of daily capacity load monitoring, collect measurement results of performance
counters on the M2000. The performance counters are measured in a 15-minute, 60-minute, or
24-hour measurement period. In normal cases, you are advised to analyze 60-minute traffic
statistics measured in peak hours every day and use an Excel file to make a graph of the capacity
load trend.
NOTE
l For details about how to collect performance counters and monitor the counters in real time, see
"Performance Management" in the M2000 online help.
l Peak hours in a day refer to the time when the BSC traffic volume reaches the maximum.
Procedure
Step 1 On the M2000 client, register a user-defined measurement task for collecting measurement
results of capacity-related counters.
Step 2 On the M2000 client, periodically collect the measurement results.
Step 3 Analyze and evaluate the measurement results by using the methods and standards provided in
this document. In addition, provide an analysis report on capacity monitoring.
----End
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3 Capacity Counter Categories and Capacity Problem
Locating Methods
Capacity Counter Categories and Capacity
Problem Locating Methods
About This Chapter
This chapter describes key performance counters related to all capacity resources and provides
the methods for identifying and troubleshooting resource bottleneck.
3.1 Capacity Counter Categories
GBSS capacity resources are categorized into radio resources, equipment resources, and
transmission resources. This section describes key performance counters and capacity expansion
specifications for these resources.
3.2 Capacity Monitoring and Problem Locating Methods
This chapter describes the methods for monitoring capacity-related counters and locating
capacity problems during routine capacity maintenance.
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3.1 Capacity Counter Categories
GBSS capacity resources are categorized into radio resources, equipment resources, and
transmission resources. This section describes key performance counters and capacity expansion
specifications for these resources.
CAUTION
l With the network development, network capacity is dynamically changing. Therefore, the
capacity expansion specifications for capacity-related counters are changeable. If a new
service is deployed or a new charging policy is used, the traffic model and number of
subscribers may change abruptly. This leads to a sudden change in the loads of network
capacity resources. In this situation, you are advised to predict and analyze the changes and
determine the capacity optimization solution for the network where traffic volume increases
rapidly, a new service needs to be deployed, or a new charging policy is used. Contact local
Huawei engineers if you require capacity evaluation and optimization services, including
capacity prediction, evaluation, adjustment, and expansion.
l The capacity expansion specifications described in this document are defined for the network
with a stable increase in the traffic volume and for reference only. These specifications can
be customized according to the actual situation.
l The capacity expansion specifications described in this section are lower than the actual alarm
generation thresholds so that capacity problems can be located in advance.
Table 3-1 Radio resources
Resource
Counter
Capacity Expansion
Specification
4.1 PCH Load
OVERLOAD rate of paging
2%
or
PCH load
70%
4.2 SDCCH Load
Congestion Rate on SDCCH
per CELL
2%
4.3 TCH Load
Congestion Rate on TCH
2%
4.4 PDCH Load
TBF congestion rate
3%
Resource
Counter
Capacity Expansion
Specification
5.1 XPU CPU Usage
Average CPU Usage of the
XPU
70%
Table 3-2 Equipment resources
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Resource
Counter
Capacity Expansion
Specification
5.2 DPU (CS) Load
DPU (CS) load
0.7 Erl/CIC
Or 0.7 Erl/IWF
5.3 DPU (PS) Load
DPU (PS) load
70%
5.4 Interface Board Load
Average Forwarding Ratio of
Interface Boards
70%
5.5 Inter-Subrack BSC
Communication
Bandwidth and Load
Peak inter-subrack traffic
usage
60%
Average inter-subrack traffic 40%
usage
Inter-subrack packet loss rate
0.01%
Table 3-3 Transmission resources (TDM transmission mode)
Resource
Counter
Capacity Expansion
Specification
6.1.1 A over TDM
(Signaling)
Transmission bandwidth
usage of the MTP2 link
40%
or
Receiving bandwidth usage
of the MTP2 link
6.2.1 A over TDM (Traffic) Percentage of busy circuits
on the A interface
70%
6.3 Ater Interface
Percentage of busy circuits
on the Ater interface
70%
6.4.1 Gb over FR
Uplink bandwidth usage of
the BC
80%
or
Downlink bandwidth usage
of the BC
6.5.1 Abis over TDM
l Flex Abis:
3%
Congestion Rate of
Dynamic Resource
Assignment (16 kbit/s)
or
Congestion Rate of
Dynamic Resource
Assignment (8 kbit/s)
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Resource
Counter
Capacity Expansion
Specification
l Non-Flex Abis:
3%
Percentage of failed
application attempts of
Abis timeslots because of
no idle timeslot (in nonFlex Abis mode)
Table 3-4 Transmission resources (IP transmission mode)
Resource
Counter
Capacity Expansion
Specification
6.1.2 A over IP (Signaling)
Receive bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
70%
or
Transmit bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
6.2.2 A over IP (Traffic)
Mean Receive Rate of an IP
Path at the IP Layer/Receive
bandwidth configured for an
IP path
70%
or
Mean Transmit Rate of an IP
Path at the IP Layer/Transmit
bandwidth configured for an
IP path
6.4.2 Gb over IP
Receive bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
70%
or
Transmit bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
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Resource
Counter
Capacity Expansion
Specification
6.5.2 Abis over IP
l Abis interface on the BSC
side:
70%
Receive bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
Or
Transmit bandwidth
requirement/Bandwidth
allocated by the transport
bearer network
l Abis interface on the BTS
side:
70%
Mean Receive Rate of an
IP Path at the IP Layer/
Receive bandwidth
configured for an IP path
or
Mean Transmit Rate of an
IP Path at the IP Layer/
Transmit bandwidth
configured for an IP path
3.2 Capacity Monitoring and Problem Locating Methods
This chapter describes the methods for monitoring capacity-related counters and locating
capacity problems during routine capacity maintenance.
3.2.1 Methods for Locating Capacity Problems
This section describes how to locate capacity problems.
In most cases, an abnormal KPI triggers the troubleshooting process. Determining the possible
top N problem cells facilitates follow-up troubleshooting. Figure 3-1 shows the general
troubleshooting process.
You are advised to analyze accessibility-related KPIs to identify the resource insufficiency that
causes access congestion. For details about resource insufficiency analysis and relevant
solutions, see3.2.2 Methods for Troubleshooting Capacity Problems.
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Figure 3-1 Flowchart for capacity problem location
NOTE
The analysis report on the capacity problem is provided after capacity data collection and analysis are
complete.
3.2.2 Methods for Troubleshooting Capacity Problems
This section describes how to troubleshoot capacity problems.
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The BSS capacity resources are correlated because of resource sharing. Insufficiency in a certain
type of resource unnecessarily indicates resource insufficiency in the entire BSS. Some capacity
problems can be resolved by resource adjustment and optimization, and others require capacity
expansion. Before expanding capacity, you are advised to comprehensively analyze related
resources. Table 3-5 lists the recommended solutions to common capacity problems.
For example, TCHs, PDCHs, and SDCCHs can be mutually converted. Therefore, insufficiency
in TCHs, PDCHs, or SDCCHs unnecessarily requires capacity expansion. If SDCCHs are
insufficient, you can decrease the number of TCHs or enable the dynamic SDCCH conversion
function. If SDCCHs, TCHs, and PDCHs are insufficient at the same time, comprehensively
analyze the three types of channels and determine whether the problem can be resolved by
channel optimization. If the problem persists, perform capacity expansion on the BSS.
Overall capacity evaluation is necessary especially for the networks where the traffic volume
increases rapidly and before a new charging policy is used. Based on the capacity evaluation,
formulate a feasible plan for monitoring network capacity and detecting resource insufficiency.
Table 3-5 Solutions to common capacity problems
If...
Then...
PCHs are
overloaded
1. Enable the dynamic CCCH conversion function.
2. Split location areas (LAs).
3. Adjust paging policies and decrease the number of pagings.
SDCCHs are
congested
Enable the dynamic SDCCH conversion function.
TCHs are
congested
1. Enable TCHHs and lower the threshold for enabling TCHHs.
PDCHs are
congested
Check whether TCHs are congested.
2. Add TRXs.
1. If TCHs are congested, add TRXs.
2. If TCHs are not congested, modify the PDCH proportion threshold.
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The control
plane (CP) is
overloaded
Expand XPU boards.
CS service
processing
boards are
overloaded
Expand DPUa/DPUc/DPUf boards.
PS service
processing
boards are
overloaded
Expand DPUd/DPUg boards.
Transmission
resources are
overloaded
Expand the transmission resource capacity.
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NOTE
If the BSC has been fully configured and board expansion is required, add a BSC.
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4 Radio Resource Monitoring
4
Radio Resource Monitoring
About This Chapter
Monitoring radio resources involves monitoring the loads of PCHs, SDCCHs, TCHs, and
PDCHs.
4.1 PCH Load
4.2 SDCCH Load
4.3 TCH Load
4.4 PDCH Load
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4 Radio Resource Monitoring
4.1 PCH Load
Related Counters
The PDCH load is indicated by the following counters:
l
RL3188: OVERLOAD rate of paging——This counter provides the percentage of CS and
PS paging overload times over the PCH on the Abis interface to all paging times.
l
PCH load——This counter is a calculation counter, which reflects the percentage of paging
times to the PCH paging capability. The formula for calculating the PCH load is as follows:
PCH load = (A330: Delivered Paging Messages for CS Service + A331: Delivered Paging
Messages for PS Service)/PCH paging capability x 100%
where, the PCH paging capability provides a basis for planning location areas (LAs)
because paging messages are sent on a basis of LA. The formula for calculating the PCH
paging capability is as follows:
PCH paging capability = [(Number of CCCH blocks - Number of CCCH blocks reserved
for AGCH) x Time for sending a BCCH multiframe] x Paging message combination
efficiency x Um interface usage between paging groups x 3600
NOTE
l Time for sending a BCCH multiframe: 0.2354s.
l Paging message combination efficiency: Efficiency for encapsulating paging messages on the Um
interface. (The efficiency is determined by the IMSI-based or TMSI-based paging policy.)
l Um interface usage between paging groups: The imbalance between paging groups and between
services imbalance regarding time decreases the Um interface usage.
For example, paging capability using common configurations in most scenarios is calculated as follows:
Paging capability = [(Number of CCCH blocks - Number of CCCH blocks reserved for AGCH) x Paging
message combination efficiency x Um interface usage between paging groups]/(51 x TDMA period)
Number of CCCH blocks: The number of message blocks for a non-combined CCCH is 9.
Number of CCCH blocks reserved for AGCH: 2
Paging message combination efficiency: 2.87 (The first paging adopts the TMSI-based paging policy and
the second paging adopts the IMSI-based paging policy.)
Um interface usage between paging groups: 80%
Therefore, the paging capability in this example is calculated as follows: Paging capability = (9-2)/0.2354
x 2.87 x 80% x 3600 = 245791 times/hour
Capacity Expansion Threshold
RL3188: OVERLOAD rate of paging > 2%
or
PCH load > 70%, and the network traffic volume is increasing constantly.
Impact on System
l
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Call MSs are paged on PCHs. In the GSM system, paging is performed on a basis of location
area (LA). If the actual paging volume in an LA exceeds the theoretical PCH paging
capacity, PCHs become congested and even overloaded. This decreases the paging success
rate and deteriorates user experience.
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l
4 Radio Resource Monitoring
The BSS reports ALM-21822 Cell PCH Congestion when PCHs in a cell are congested.
Relationship with Other Counters
None
Recommended Measures
l
Enable the GBFD-511503 Dynamic Multiple CCCH feature to expand the PCH capacity.
l
Split an LA to reduce its capacity.
4.2 SDCCH Load
Related Counters
GSM signaling services are carried on SDCCHs. An MS needs to occupy an SDCCH each time
the MS initiates an SMS, performs a location update, or sets up a call. If SDCCHs are insufficient,
an MS cannot perform services. In this situation, the BSS considers SDCCHs as congested and
increments the number of SDCCH congestion occurrences by 1. Causes for insufficient SDCCHs
include inappropriate network planning and service surge during regional events.
The SDCCH load is indicated by the following counter:
RR370: Congestion Rate on SDCCH per CELL ——This counter provides the percentage of
times that all requested SDCCHs are occupied to all SDCCH request times. It indicates the
SDCCH congestion due to insufficient resources.
Capacity Expansion Threshold
RR370: Congestion Rate on SDCCH per CELL > 2%
Impact on System
GSM signaling services are carried on SDCCHs. An MS needs to occupy an SDCCH each time
the MS initiates an SMS, performs a location update, or sets up a call. If SDCCHs are insufficient,
an MS fails to initiate SMS, a calling MS cannot access the network, and a called MS cannot
respond. SDCCHs are vital to process services, and therefore normal operation of SDCCHs
needs to be preferentially ensured. In normal cases, enable the dynamic SDCCH conversion
function to ensure that SDCCHs are sufficient.
Relationship with Other Counters
SDCCHs, TCHs, and PDCHs need to be analyzed comprehensively because Huawei GBSS has
implemented dynamic conversions among SDCCHs, TCHs, and PDCHs.
Recommended Measures
l
Enable the dynamic SDCCH conversion function.
l
Expand TRX capacity if SDCCHs, TCHs and PDCHs are all congested at the same time
or SDCCHs are still congested after the dynamic SDCCH conversion function is enabled.
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4 Radio Resource Monitoring
4.3 TCH Load
Related Counters
CS services are carried on TCHs. If TCHs are insufficient, an MS cannot perform CS services.
In this situation, the BSS considers TCHs as congested and increments the number of TCH
congestion occurrences by 1.
The TCH load is indicated by the following counter:
K3045: Congestion Rate on TCH ——This counter provides the TCH congestion rate. It
indicates the percentage of TCH request failures due to no idle TCHs to all TCH requests.
Capacity Expansion Threshold
K3045: Congestion Rate on TCH > 2%
Impact on System
If TCHs are insufficient, CS services have difficulties accessing the network. This greatly
deteriorates user experience.
Relationship with Other Counters
SDCCHs, TCHs, and PDCHs need to be analyzed comprehensively because Huawei GBSS has
implemented dynamic conversions among SDCCHs, TCHs, and PDCHs.
Recommended Measures
l
Enable TCHHs and lower the threshold for enabling TCHHs. Note that the voice quality
of TCHHs is a little poorer than that of TCHFs.
l
Expand TRX capacity.
4.4 PDCH Load
Related Counters
PS signaling and data are carried on PDCHs. A PDCH can be shared by a maximum of 16 MSs
in the downlink. PDCHs can be preempted by CS services. Therefore, TCHs and PDCHs need
to be analyzed comprehensively.
The PDCH load is indicated by the counters related to the temporary block flow (TBF)
congestion rate. TBFs are data blocks transmitted over PDCHs. The TBF congestion rate consists
of the uplink TBF congestion rate and the downlink TBF congestion rate. In normal cases, the
downlink PS data throughput is higher than the uplink PS data throughput. Therefore, the
downlink TBF congestion rate is the primary focus of PDCH load monitoring.
l
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Uplink TBF Congestion Rate: This counter provides the percentage of TBF establishment
failures on the uplink due to insufficient resources.
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4 Radio Resource Monitoring
Downlink TBF Congestion Rate: This counter provides the percentage of TBF
establishment failures on the downlink due to insufficient resources.
Capacity Expansion Threshold
Uplink TBF Congestion Rate > 3%
Or
Downlink TBF Congestion Rate > 3%
Impact on System
If PDCHs are insufficient, the GPRS/EDGE service rate decreases, and even some MSs cannot
process PS services.
Relationship with Other Counters
SDCCHs, TCHs, and PDCHs need to be analyzed comprehensively because Huawei GBSS has
implemented dynamic conversions among SDCCHs, TCHs, and PDCHs.
Recommended Measures
l
l
Take measures based on specific causes for insufficient PDCHs.
1.
The PDCH proportion threshold for a cell is set to a small value, and therefore few
TCHs can be converted to PDCHs. As a result, PDCHs are insufficient but some TCHs
are idle during peak hours. In this situation, increase the PDCH proportion threshold.
2.
The channels in a cell are insufficient, and therefore TCHs and PDCHs are insufficient
for processing services during peak hours. In this situation, optimize related
parameters or expand TRX capacity.
Check the following counters to determine the root causes for insufficient PDCHs:
– Percentage of PDCH application failures due to the limited PDCH proportion threshold
= R9395: Number of PDCH Application failures For CELL PDCH Ratio Thresh/R9393:
Number Of PDCH Application Attempts
– Percentage of PDCH application failures due to no TCH available = R9394: Number
of PDCH Application Failures due to no Convertable TCHs/R9393: Number Of PDCH
Application Attempts
If the PDCH proportion threshold is set to a value that is too small, increase the threshold.
If TCHs and PDCHs in a cell are insufficient during peak hours, expand TRX capacity.
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5
5 Equipment Resource Monitoring
Equipment Resource Monitoring
About This Chapter
Monitoring equipment resources involves monitoring the loads of XPU boards, DPUa/DPUc/
DPUf boards, DPUd/DPUg boards, interface boards, and inter-subrack BSC communication
resources.
5.1 XPU CPU Usage
5.2 DPU (CS) Load
5.3 DPU (PS) Load
5.4 Interface Board Load
5.5 Inter-Subrack BSC Communication Bandwidth and Load
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5.1 XPU CPU Usage
Related Counters
The XPU board, the main processing board of a BSC, performs BSS resource scheduling and
processes services. The capacity of the XUP board is indicated only by its CPU usage.
XPU boards on the BSC are responsible for processing control-plane services. Therefore, the
XPU CPU usage indicates the load of the BSC control plane. The XPU CPU usage is indicated
by the following counter:
AR9780: Average CPU Usage of the XPU——This counter provides the average XPU CPU
usage within a measurement period. It indicates the load and operating performance of the XPU
CPU within a measurement period.
Capacity Expansion Threshold
[AR9780: Average CPU Usage of the XPU] > 70%
Impact on System
l
If the CPU is overloaded, the BSC triggers flow control to discard messages such as paging
messages and channel request messages to restrict service access. In severe cases, a large
number of MSs have difficulties accessing the network and some BSC maintenance
functions, such as collecting log files and obtaining traffic measurement result files, are
disabled automatically.
l
If the XPU CPU is overloaded, the BSS reports ALM-20256 CPU Overload.
Relationship with Other Counters
None
Recommended Measures
Observe the AR9780: Average CPU Usage of the XPU counter to monitor the XPU CPU load
during peak hours every day.
l
On a network that has a slow increase in traffic volume, expand XPU capacity if the average
CPU usage exceeds 70% during peak hours within more than three consecutive days.
l
On a network that has a fast increase in traffic volume, perform capacity expansion analysis
and draft the pre-expansion scheme if the average CPU usage exceeds 50%.
5.2 DPU (CS) Load
Related Counters
l
DPUa, DPUc, and DPUf boards process speech multiplexing and demultiplexing. The DPU (CS)
load is determined based on the CS traffic volume (CSERL).
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The DPU (CS) load is determined based on the average traffic volume on the DPU (CS) board
during peak hours, which can be calculated by using the following formula:
DPU (CS) load = [ZK3014: Traffic Volume on TCH (Traffic Channel) per BSC]/[DPU (CS)
specification x Number of DPU (CS) boards]
NOTE
l DPU (CS) boards are DPUa, DPUc, and DPUf boards. For details about their specifications, see
BSC6900 GSM Hardware Description.
l The processing capability of a DPU (CS) board in TDM transmission mode is different from that in IP
transmission mode. For example, a DPUc board supports 960 TCHFs in TDM transmission mode and
supports 3740 interworking functions (IWFs) in IP transmission mode.
Capacity Expansion Threshold
[DPU (CS) load] > 0.7 erl/CIC
Impact on System
DPU (CS) boards are responsible for encoding and decoding CS data. If these boards are
insufficient, CS services cannot be processed properly.
Relationship with Other Counters
None
Recommended Measures
Expand the capacity of DPUa/DPUc/DPUf boards.
5.3 DPU (PS) Load
Related Counters
DPUd and DPUg boards performs the coding for PS services. The DPU (PS) load indicates the
PDCH load over the Um interface.
The DPU (PS) load is determined based on the proportion of occupied PDCHs on the DPU (PS)
board during peak hours, which can be calculated by using the following formula:
DPU (PS) load = [AS9204: Average Number of PDCHs Occupied per BSC]/[DPU (PS)
specification x Number of DPU(PS) boards]
NOTE
DPU (PS) boards are DPUd and DPUg. For details about their specifications, see BSC6900 GSM Hardware
Description.
Capacity Expansion Threshold
[DPU (PS) load] > 70%
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Impact on System
If DPU (PS) boards are insufficient, some PDCHs cannot be activated. As a result, the PS data
rate decreases or MSs have difficulties accessing the network to process PS services.
Relationship with Other Counters
None
Recommended Measures
Expand the capacity of DPUd/DPUg boards.
5.4 Interface Board Load
Related Counters
When monitoring the load of interface boards, check whether the forwarding rate of data flow
exceeds the designed maximum forwarding rate and whether the CPU of the interface board is
overloaded.
The user-plane interface board load is indicated by the following counters:
AR9705a: Average Forwarding Ratio of Interface Boards——This counter provides the average
forwarding load of an interface board within a measurement period. The forwarding load refers
to the percentage of the actual forwarding rate to the designed maximum forwarding rate of an
interface board. It indicates the load and operating performance of an interface board within a
measurement period.
AR9700: Average CPU Usage of the INT——This counter provides the average CPU usage of
an interface board within a measurement period. It indicates the load and operating performance
of the CPU on an interface board within a measurement period.
NOTE
Interface boards are A, Abis, Gb, and Ater interface boards on the BSC.
Capacity Expansion Threshold
[AR9705a: Average Forwarding Ratio of Interface Boards] > 70%
or
[AR9700: Average CPU Usage of the INT] > 70%
Impact on System
l
If the forwarding load over an interface is too high, the BSS may discard some messages.
This deteriorates the quality of service (QoS) of CS and PS services.
l
If the forwarding load of an interface board is too high, the BSS reports ALM-20275
Forwarding Overload of An Interface Board.
Relationship with Other Counters
None
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Recommended Measures
Expand the capacity of interface boards.
5.5 Inter-Subrack BSC Communication Bandwidth and
Load
Related Counters
Messages are forwarded between subracks in a BSC. If the forwarding load is too high, the SCU
board may become overloaded and discard some messages.
Inter-subrack BSC communication bandwidths are as follows:
l
The inter-subrack BSC communication bandwidth is 4 Gbit/s when active and standby
SCUa boards are configured.
l
The inter-subrack BSC communication bandwidth is 40 Gbit/s when active and standby
SCUb boards are configured.
l
The preceding bandwidths are halved when a standalone SCUa or SCUbSCUb is running.
Inter-subrack BSC communication is monitored by using the following counters:
l
Peak inter-subrack traffic usage:
Peak inter-subrack traffic usage = [HR9732a: Peak Inter-Subrack Transmitting Traffic]/
Inter-subrack bandwidth x 100%
l
Average inter-subrack traffic usage:
Average inter-subrack traffic usage = [AR9732a: Average Inter-Subrack Transmitting
Traffic]/Inter-subrack bandwidth x 100%
l
Inter-subrack packet loss rate
Inter-subrack packet loss rate = [R9732a: Number of Discarded Inter-Subrack Packets]/
[R9732b: Number of Sent Inter-Subrack Packets] x 100%
Capacity Expansion Threshold
l
Peak inter-subrack traffic usage > 60% (Prewarning and analysis is required.)
l
Average inter-subrack traffic usage > 40% (Prewarning and analysis is required.)
l
Inter-subrack packet loss rate > 0.01% (Prewarning and analysis is required.)
Impact on System
l
If the forwarding load over an interface is too high, the BSS may discard some messages.
This deteriorates the quality of service (QoS) of CS and PS services. The Main Processing
Subrack (MPS) is connected to the Extended Processing Subrack (EPS) using the port trunk
group on the SCU panel. When the inter-subrack BSC communication capacity is close to
the overload threshold, the QoS of CS and PS services and network KPIs deteriorate, and
the BSS becomes unstable.
l
If the actual link bandwidth usage of the port trunk group on the SCU panel exceeds the
congestion threshold (70%) or the packet loss rate over a link exceeds the congestion
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threshold (0.02%) for 5 minutes or longer, the BSS reports ALM-20277 Communication
Congestion Between Subracks.
Relationship with Other Counters
None
Recommended Measures
The inter-subrack BSC communication capacity seldom becomes overloaded. If this occurs,
contact Huawei maintenance engineers for in-depth analysis and troubleshooting.
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6 Transmission Resource Monitoring
Transmission Resource Monitoring
About This Chapter
Monitoring transmission resources involves monitoring the loads of A, Ater, Gb, and Abis
interface transmission resources.
6.1 A Interface (Signaling)
Signaling System No. 7 (SS7) links are basic signaling links for processing CS service and
transmitting signaling between the BSC and the MSC.
6.2 A Interface (Traffic)
The circuit identification code (CIC) identifies a voice circuit between the BSC and the MSC.
Each call corresponds to one CIC.
6.3 Ater Interface
The Ater interface is the interface between the BM subrack and the TC subrack when the TC
subrack is configured on the MSC side. The percentage of busy circuits in all circuits on the
Ater interface reflects the load of Ater transmission resources.
6.4 Gb Interface
The Gb interface is between the BSC and the SGSN. The Gb interface can use either the TDM
or IP transmission.
6.5 Abis Interface
The Abis interface is between the BSC and the BTS, carries CS and PS services, radio signaling
links (RSLs) and operation and maintenance links (OMLs). The Abis interface can use either
the TDM or IP transmission.
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6.1 A Interface (Signaling)
Signaling System No. 7 (SS7) links are basic signaling links for processing CS service and
transmitting signaling between the BSC and the MSC.
6.1.1 A over TDM (Signaling)
Related Counters
The load of SS7 links over the A interface is indicated by the following counters:
RL9808: Transmission bandwidth usage of the MTP2 link——This counter provides the rate
of the actually used bandwidth to the configured bandwidth of the MTP2 link within a
measurement period. It indicates the usage of the MTP2 link.
RL9809: Receiving bandwidth usage of the MTP2 link——This counter provides the rate of the
actually used bandwidth to the configured bandwidth of the MTP2 link. It indicates the usage
of the MTP2 link.
Capacity Expansion Threshold
[RL9808: Transmission bandwidth usage of the MTP2 link] > 40%
Or
[RL9809: Receiving bandwidth usage of the MTP2 link] > 40%
Impact on System
SS7 link overload causes congestion and packet loss. This affects the signaling procedure and
CS service processing.
Relationship with Other Counters
None
Recommended Measures
Add SS7 links.
l
If the MSC supports the high-speed signaling link (2 Mbit/s), configure 2 Mbit/s signaling
links for the BSC. Due to the large capacity of the BSC6900, when the traffic increases,
the 64 kbit/s narrowband signaling link with a single signaling point does not meet the
bandwidth requirements of SS7 links.
l
If the MSC supports only the narrowband SS7 signaling link, configure 64 kbit/s signaling
links for the BSC. If the number of 64 kbit/s signaling links configured for the BSC exceeds
16, configure more signaling points.
l
If the BSC has been configured with the high-speed signaling link (2 Mbit/s), expand the
bandwidth or add more such signaling links.
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6.1.2 A over IP (Signaling)
Related Counters
In IP transmission mode, the BSC and BTS are configured with FE or GE ports and use 100 or
1000 MHz transmission bandwidth. This basically meets the actual bandwidth requirements.
Therefore, monitor the transmission resource load from two perspectives in IP transmission
mode: transmission load of ports on the BSC or the BTS, and transmission load allocated by the
bearer network.
The load of SS7 links over the A interface is indicated by the following counters:
T7263: Average Transmit Rate of an SCTP Link IP Layer——This counter provides the transmit
rate of an SCTP link at the IP layer within a measurement period.
T7268: Average Receive Rate of an SCTP Link IP Layer——This counter provides the receive
rate of an SCTP link at the IP layer within a measurement period.
Capacity Expansion Threshold
[T7263: Average Transmit Rate of an SCTP Link IP Layer]/Bandwidth allocated by the
transmission bearer network > 70%
Or
[T7268: Average Receive Rate of an SCTP Link IP Layer]/Bandwidth allocated by the
transmission bearer network > 70%
NOTE
l SCTP links have no bandwidth configurations. Therefore, when STCP links are used, monitor the
bandwidth resources occupied by SCTP links and check whether the transmission resources on the
bearer network meet the bandwidth requirements.
Impact on System
l
SS7 link overload causes congestion and packet loss. This affects the signaling procedure
and CS service processing.
l
If SCTP links are congested, the BSS reports ALM-21542 SCTP Link Congestion.
Relationship with Other Counters
None
Recommended Measures
Add SCTP links. To ensure the control plane reliability, configure SCTP links in load sharing
mode. The configuration rule is as follows:
1.
At least two SCTP links are configured.
2.
At least one SCTP link is configured for each pair of XPU boards.
3.
A maximum of one SCTP link is configured for each subsystem on a XPU board.
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6.2 A Interface (Traffic)
The circuit identification code (CIC) identifies a voice circuit between the BSC and the MSC.
Each call corresponds to one CIC.
6.2.1 A over TDM (Traffic)
Related Counters
The load of transmission resources over the A interface is indicated by the percentage of busy
circuits over the A interface. A circuit identification code (CIC) identifies a circuit over the A
interface. Each call corresponds to a CIC.
Percentage of busy circuits on the A interface = [AL0055: Mean number of busy circuits on the
A interface]/[AL0055: Mean number of busy circuits on the A interface + AL0054: Mean
number of idle circuits on the A interface]
Capacity Expansion Threshold
[Percentage of busy circuits on the A interface] > 70%
Impact on System
Insufficient circuit transmission resources on the A interface lead to circuit assignment and call
setup failures. This deteriorates user experience.
Relationship with Other Counters
None
Recommended Measures
Expand transmission resources over the A interface.
6.2.2 A over IP (Traffic)
Related Counters
In IP transmission mode, the BSC and BTS are configured with FE or GE ports and use 100 or
1000 MHz transmission bandwidth. This basically meets the actual bandwidth requirements.
Therefore, whether the transmission resources allocated by the bearer network meet
requirements is the focus of capacity monitoring in IP transmission mode.
l
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Load of the bearer network = [T7123: Mean Receive Rate of the FEGE Ethernet Port]/
Bandwidth allocated by the bearer network, or [T7128: Mean Transmit Rate of the FEGE
Ethernet Port]/Bandwidth allocated by the bearer network
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l
6 Transmission Resource Monitoring
Load of the Ethernet port = [T7123: Mean Receive Rate of the FEGE Ethernet Port]/
Bandwidth of the physical Ethernet port, or [T7128: Mean Transmit Rate of the FEGE
Ethernet Port]/Bandwidth of the physical Ethernet port
NOTE
l In IP transmission mode, the BSC and BTS are configured with FE or GE ports and use 100 or 1000
MHz transmission bandwidth.
l The bandwidth allocated by the bearer network refers to the bandwidth allocated by the A interface
backbone network.
Capacity Expansion Threshold
Load of the bearer network > 70%
Or
Load of the Ethernet port > 70%
Impact on System
l
Insufficient circuit transmission resources on the A interface lead to circuit assignment and
call setup failures. This deteriorates user experience.
l
If the load of physical ports exceeds the alarm threshold, the BSS reports ALM-21583 Port
Congestion.
Relationship with Other Counters
None
Recommended Measures
l
Ask the bearer network vendor to increase the network capacity when the load of the bearer
network exceeds 70%.
l
Expand interface boards when the load of the Ethernet port exceeds 70%.
6.3 Ater Interface
The Ater interface is the interface between the BM subrack and the TC subrack when the TC
subrack is configured on the MSC side. The percentage of busy circuits in all circuits on the
Ater interface reflects the load of Ater transmission resources.
Related Counters
The load of Ater transmission resources is indicated by the following counter:
Percentage of busy circuits on the Ater interface = [AL125A: Mean number of busy circuits on
the Ater interface]/[AL1259: Mean number of idle circuits on the Ater interface + AL125A:
Mean number of busy circuits on the Ater interface]
Capacity Expansion Threshold
[Percentage of busy circuits on the Ater interface] > 70%
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Impact on System
Insufficient circuit resources on the Ater interface lead to circuit assignment and call setup
failures. This deteriorates user experience.
Relationship with Other Counters
None
Recommended Measures
Expand transmission resources over the Ater interface.
6.4 Gb Interface
The Gb interface is between the BSC and the SGSN. The Gb interface can use either the TDM
or IP transmission.
6.4.1 Gb over FR
Related Counters
In Gb over FR mode, the load of transmission resources on the Gb interface is indicated by the
following counters:
RL9608: Uplink bandwidth usage of the BC——This counter provides the percentage of L9607:
Uplink bandwidth actually used on the BC to L9606: Configured bandwidth of the BC.
RL9610: Downlink bandwidth usage of the BC——This counter provides the percentage of
L9609: Downlink bandwidth actually used on the BC to L9606: Configured bandwidth of the
BC.
Capacity Expansion Threshold
[RL9608: Uplink bandwidth usage of the BC] > 80%
Or
[RL9610: Downlink bandwidth usage of the BC] > 80%
Impact on System
Insufficient transmission resources on the Gb interface lead to a low GPRS or EDGE service
rate and even network access failures.
Relationship with Other Counters
None
Recommended Measures
Expand transmission resources over the Gb interface.
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l
The license for the Gb over FR mode is required. Add license resources if needed.
l
If the physical transmission resources on the Gb interface are insufficient, add physical
transmission resources and configure related data.
6.4.2 Gb over IP
Related Counters
In IP transmission mode, the BSC and BTS are configured with FE or GE ports and use 100 or
1000 MHz transmission bandwidth. This basically meets the actual bandwidth requirements.
Therefore, whether the transmission resources allocated by the bearer network meet
requirements is the focus of capacity monitoring in IP transmission mode.
The Gb interface is not configured with IP paths. The load of Gb transmission resources is
indicated by the following counters:
T7123: Mean Receive Rate of the FEGE Ethernet Port——This counter provides the receive
rate of an FE or GE Ethernet port at the data link layer within a measurement period. It indicates
the data flow on an FE or GE Ethernet port at the data link layer.
T7128: Mean Transmit Rate of the FEGE Ethernet Port——This counter provides the transmit
rate of an FE or GE Ethernet port at the data link layer within a measurement period. It indicates
the data flow on an FE or GE Ethernet port at the data link layer.
Capacity Expansion Threshold
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Rate of Ethernet port] > 70%
l
[T7128: Mean Transmit Rate of the FEGE Ethernet Port/Rate of Ethernet port] > 70%
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port]/Bandwidth allocated by the bearer
network > 70%
l
[T7128: Mean Transmit Rate of the FEGE Ethernet Port]/Bandwidth allocated by the bearer
network > 70%
Impact on System
l
Insufficient transmission resources on the Gb interface lead to a low GPRS or EDGE service
rate and even network access failures.
l
If the load of IP paths exceeds the alarm threshold, the BSS reports ALM-21582 Path
Congestion.
l
If the load of physical ports exceeds the alarm threshold, the BSS reports ALM-21583 Port
Congestion.
Relationship with Other Counters
None
Recommended Measures
In Gb over IP mode, the BSC interface board capacity is generally sufficient. Therefore, focus
on the transmission resources allocated by the bearer network on the Gb interface. You are
advised to:
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l
Expand Gb interface boards when the following condition is met: [T7123: Mean Receive
Rate of the FEGE Ethernet Port/Rate of the Ethernet port] > 70%, or [T7128: Mean
Transmit Rate of the FEGE Ethernet Port/Rate of the Ethernet port] > 70%
l
Notify the bearer network vendor of bandwidth expansion needs when the following
condition is met: [T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth
allocated by the bearer network] > 70%, or [T7128: Mean Transmit Rate of the FEGE
Ethernet Port/Bandwidth allocated by the bearer network] > 70%
l
Apply for a license for the Gb over IP mode and ensure that license resources are sufficient.
6.5 Abis Interface
The Abis interface is between the BSC and the BTS, carries CS and PS services, radio signaling
links (RSLs) and operation and maintenance links (OMLs). The Abis interface can use either
the TDM or IP transmission.
6.5.1 Abis over TDM
Flex Abis
l
Related Counters
In Flex Abis mode, all Abis TDM timeslots on the BTS can be dynamically allocated. When
the BTS receives a CS or PS service request, Abis timeslots are allocated based on the
actual requirements in real time. In this mode, the load of Abis transmission resources is
indicated by the following counters:
RR2752: Congestion Rate of Dynamic Resource Assignment (16 kbit/s)——This counter
provides the congestion rate of dynamic allocation of 16 kbit/s Abis resources.
RR2751: Congestion Rate of Dynamic Resource Assignment (8 kbit/s)——This counter
provides the congestion rate of dynamic allocation of 8 kbit/s Abis resources.
l
Capacity Expansion Threshold
[RR2752: Congestion Rate of Dynamic Resource Assignment (16 kbit/s)] > 3%
Or
[RR2751: Congestion Rate of Dynamic Resource Assignment (8 kbit/s)] > 3%
l
Impact on System
Insufficient transmission resources on the Abis interface lead to network access failures.
This deteriorates user experience.
l
Relationship with Other Counters
None
l
Recommended Measures
Expand transmission resources over the Abis interface.
Non-Flex Abis Mode
l
Related Counters
In non-Flex Abis mode, Abis timeslots, except idle Abis timeslots, bear one-to-one mapping
with the TCHs and PDCHs. Therefore, Abis timeslot capacity expansion is required if TCH
and PDCH capacity expansion is performed. In this mode, the usage of idle Abis timeslots
is indicated by the following counters:
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Percentage of Abis timeslot application failures due to no idle timeslot (in non-Flex Abis
mode) = [R9109: Number of Unsuccessful Application Attempts of Abis Timeslot Because
of No Idle Timeslot]/[R9101: Number of Application Attempts of Abis Timeslot]
l
Capacity Expansion Threshold
[Percentage of Abis timeslot application failures due to no idle timeslot (in non-Flex Abis
mode)] > 3%
l
Impact on System
Insufficient transmission resources on the Abis interface lead to difficulties in improving
the PS service rate.
l
Relationship with Other Counters
None
l
Recommended Measures
Expand transmission resources over the Abis interface.
6.5.2 Abis over IP
Related Counters
The BTS in IP transmission mode is typically configured with FE ports and uses 100 MHz
transmission bandwidth. This basically meets the GSM service requirements. Therefore, monitor
the transmission resource load of a BTS from two perspectives in Abis over IP mode: bandwidth
usage of physical Abis interface boards on the BSC, and whether the transmission resources
allocated by the bearer network meet Abis transmission bandwidth requirements. The load of
IP transmission resources over the Abis interface is indicated by forward or backward bandwidth
allocated to IP transport adjacent node and transmit or receive rate of the FE/GE Ethernet port.
l
T7123: Mean Receive Rate of the FEGE Ethernet Port —— This counter provides the
receive rate of an FE or GE Ethernet port at the data link layer within a measurement period.
It indicates the data flow on an FE or GE Ethernet port at the data link layer.
l
T7128: Mean Transmit Rate of the FEGE Ethernet Port —— This counter provides the
transmit rate of an FE or GE Ethernet port at the data link layer within a measurement
period. It indicates the data flow on an FE or GE Ethernet port at the data link layer.
Capacity Expansion Threshold
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth of the physical Ethernet
port] > 70%
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth of the physical Ethernet
port] > 70%
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth allocated by the bearer
network] > 70%
l
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth allocated by the bearer
network] > 70%
NOTE
l In IP transmission mode, the BSC and BTS are configured with FE or GE ports and use 100 or 1000
MHz transmission bandwidth.
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GBSS14.0
GBSS Capacity Monitoring Guide
6 Transmission Resource Monitoring
Impact on System
l
Insufficient transmission resources on the Abis interface decrease PS service rate, degrade
voice quality and even lead to network access failures.
l
If the load of physical ports exceeds the alarm threshold, the BSS reports ALM-21583 Port
Congestion.
Relationship with Other Counters
None
Recommended Measures
l
Expand Abis interface boards when the following condition is met: [T7123: Mean Receive
Rate of the FEGE Ethernet Port/Bandwidth allocated by the bearer network] > 70%, or
[T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth allocated by the bearer
network] > 70%
l
Focus on checking whether the bandwidth allocated by the IP bearer network is sufficient.
Ask the bearer network vendor to increase the network capacity when the following
condition is met: [T7123: Mean Receive Rate of the FEGE Ethernet Port/Bandwidth
allocated by the bearer network] > 70%, or [T7128: Mean Transmit Rate of the FEGE
Ethernet Port/Bandwidth allocated by the bearer network] > 70%.
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Copyright © Huawei Technologies Co., Ltd.
32