This document includes capacity Mgt. for HUAWEI system...
RAN14.0
Capacity Monitoring Guide
Issue
Draft A
Date
2012-02-15
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 a 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]
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About This Document
About This Document Purpose Traffic on a mobile telecommunications network, especially a new network, increases by the day. To support the increasing traffic, more and more resources are required, such as signaling processing resources, transmission resources, and air interface resources. If any type of network resource is insufficient, user experience is affected (for example, the call drop rate increases). This means that real-time resource monitoring, timely resource bottleneck detection, and proper network expansion are critical to good user experience on a mobile telecommunications network. This document describes how to monitor usage of various network resources, locate network resource bottlenecks, and perform network expansion in a timely manner. Guidelines provided in this document are applicable to BSC6900 and BTS3900 series base stations, but can only be used as references for RNCs and NodeBs of earlier versions.
Audience This document is intended for network maintenance personnel.
Organization This document consists of the following chapters. Chapter
Description
1 Network Resource Monitoring Methods
Describes basic concepts associated with network resources, including definitions and monitoring activities.
2 Network Resource Counters
Describes various network resources.
3 HSPA Related Resources
Describes how to monitor network resources when HSPA is enabled.
4 Diagnosis of Problems Related to Network Resources
Provides fault analysis and locating methods that experienced WCDMA network maintenance personnel can use to handle network congestion or overload events efficiently.
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About This Document
Chapter
Description
5 Counter Definitions
Lists all performance counters mentioned in the other chapters. These counters help in monitoring network resources and designing resource analyzing instruments.
Change History Changes between document issues are cumulative. Therefore, the latest document issue contains all changes made in previous issues.
Changes in Draft A (2012-02-15) This is the draft for RAN14.0.
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Contents
Contents About This Document .................................................................................................................... ii 1 Network Resource Monitoring Methods ................................................................................. 1 1.1 Network Resource Introduction ....................................................................................................................... 1 1.2 Resource Monitoring Procedure....................................................................................................................... 3
2 Network Resource Counters ....................................................................................................... 5 2.1 Uplink Load ..................................................................................................................................................... 5 2.2 Downlink Load................................................................................................................................................. 7 2.3 CE Usage.......................................................................................................................................................... 7 2.4 OVSF Code Usage ........................................................................................................................................... 9 2.5 Iub Bandwidth ................................................................................................................................................ 10 2.6 SPU CPU Load .............................................................................................................................................. 10 2.7 DPU DSP Load .............................................................................................................................................. 11 2.8 Interface Board CPU Load ............................................................................................................................. 11 2.9 Common Channels ......................................................................................................................................... 11 2.10 NodeB CPU Load ........................................................................................................................................ 12 2.11 WMPT CNBAP Load ................................................................................................................................... 12
3 HSPA Related Resources ........................................................................................................... 14 3.1 HSDPA ........................................................................................................................................................... 14 3.1.1 Power Resources ................................................................................................................................... 14 3.1.2 Code Resources..................................................................................................................................... 15 3.2 HSUPA ........................................................................................................................................................... 16 3.2.1 CE Resources ........................................................................................................................................ 16 3.2.2 RTWP.................................................................................................................................................... 16
4 Diagnosis of Problems Related to Network Resources ....................................................... 17 4.1 Call Blocks in the Basic Call Flow ................................................................................................................ 17 4.2 Call Congestion Counters............................................................................................................................... 19 4.2.1 Performance Counters Associated with Paging Loss ............................................................................ 19 4.2.2 Performance Counters Associated with RRC Congestion Rates ........................................................... 19 4.2.3 Performance Counters Associated with RAB Congestion Rates .......................................................... 20 4.3 Signaling Storms and Solutions ..................................................................................................................... 21 4.4 Resource Analysis .......................................................................................................................................... 22
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4.4.2 CE Resource Consumption Analysis .................................................................................................... 24 4.4.3 Code Resource Usage Analysis ............................................................................................................. 26 4.4.4 Iub Resource Analysis........................................................................................................................... 27 4.4.5 Power Resource Analysis ...................................................................................................................... 28 4.4.6 SPU CPU Usage Analysis ..................................................................................................................... 29 4.4.7 DPU DSP and Interface Board CPU Usage Analysis ........................................................................... 30 4.4.8 PCH Usage Analysis ............................................................................................................................. 31 4.4.9 FACH Usage Analysis .......................................................................................................................... 32
5 Counter Definitions .................................................................................................................... 34
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1 Network Resource Monitoring Methods
Network Resource Monitoring Methods There are two methods of monitoring system resources and detecting resource bottlenecks: z
Prediction-based monitoring: This is a proactive approach wherein various network resources are monitored simultaneously.
You can monitor usage of a network resource (for example, the downlink transmit power of a cell), predict the resource usage trend and impacts, and determine whether to perform network expansion after comparing the detected resource usage with a preset upper threshold. After detecting that usage of a resource is higher than its upper threshold for a long time (for example, a cell remains overloaded during busy hours for several consecutive days), you can split the cell or add carriers for network expansion. This approach, which applies to daily resource monitoring, is easy to implement and can be used to determine high-load cells and RNCs. This chapter describes the procedure for monitoring network resources. NOTE For details on network resources, see chapter 2 "Network Resource Counters." For details on HSPA-associated resources, see chapter 3 "HSPA Related Resources." z
Problem-driven analysis: When a network performance counter deteriorates (for example, calls are dropped), a thorough analysis is performed. This method is applicable to analysis upon network congestion. This method requires more analysis instruments and skills than the prediction-based monitoring method, but can use the current system and eliminates the need for an immediate network expansion. For details on this method, see chapter 4 "Diagnosis of Problems Related to Network Resources." NOTE In addition to the preceding two methods, other methods may also be used by network maintenance engineers for system problem analysis.
1.1 Network Resource Introduction The network resources that can be monitored are as follows: z
Received total wideband power (RTWP): indicates the total wideband power received by a base station within a bandwidth (namely, the uplink load generated due to the receiver noise, external radio interference, and uplink traffic). This is a counter for measuring uplink load, similar to the received signal strength counter (RSSI) in the CDMA system. RSSI is a downlink load measurement, indicating the total channel power received by a UE.
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z
Transmitting carrier power (TCP): indicates the full-carrier power transmitted by a cell and is a counter for monitoring downlink load. This counter value is limited by the maximum transmission capability of the power amplifier at a NodeB.
z
Orthogonal variable spreading factor (OVSF): indicates the downlink OVSF code resource. For a cell, only one OVSF code tree is available in the downlink direction.
z
Channel element (CE): indicates the baseband processing resource. CEs are managed and shared at the NodeB level. For a new network, this counter has a small start value to lower capital expenditure (CAPEX). Generally, CEs are the most likely resource bottleneck that results in network congestion.
z
Iub interface resource: On an IP transport network, uplink and downlink Iub interface bandwidth can be dynamically adjusted for both NodeBs and RNCs. Generally, transport resource bottlenecks do not result from insufficient capacities of interface boards but from low bandwidth available on the IP transport network.
z
SPU: indicates the signaling processing unit on an RNC. An RNC supports various types of SPUs. SPUs process air interface signaling and manage transport resources. They are the most likely network resource bottleneck.
z
MPU: indicates the main control processing unit on an RNC. It manages control-plane resources, user-plane resources, and transport resources. If provided on an SPUb board, the MPU subsystem may be overloaded.
z
DPU: indicates the user-plane processing unit on an RNC. It distributes user-plane service data. With rapid development of mobile broadband (MBB), more and more DPU resources are consumed. There is a high possibility that the preset DPU resource capability cannot meet the requirements for the rapid development.
z
WCDMA main processing and transmission unit (WMPT): The WMPT performs site transmission, signaling, and system management. CPU overload of the WMPT will cause a decrease in system processing capabilities, therefore affecting NodeB-related KPIs.
z
Paging channel (PCH): The PCH usage is directly related to the LAC area plan and PCH state transition. PCH overload will cause a decrease in the paging success ratio.
z
Random access channel (RACH) and forward access channel (FACH): The RACH and FACH carry signaling and some user-plane data. RACH/FACH overload will cause a decrease in access success ratio and affect user experience.
Figure 1-1 shows allocation of the preceding network resources. Figure 1-1 Allocation of radio resources that can be monitored
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1.2 Resource Monitoring Procedure This section describes the resource monitoring procedure. This procedure is easy to implement and is applicable to most scenarios. For a newly constructed network, you can monitor only one resource. Once detecting that this resource exceeds its upper threshold, check whether other resources exceed their upper thresholds. z
If yes, the cell or NodeB is overloaded. Perform network expansion.
z
If no, the cell or NodeB is not necessarily overloaded. In this case, network expansion is not mandatory and the problem can be solved by other adjustments or optimizations.
For example, the CE usage is more than 70% but the usages of other resources such as RTWP, TCP, and OVSF codes are within their allowed ranges. In this case, CE resources are insufficient but the cell is not overloaded. To solve the problem in this example, configure licenses allowing more CEs or add baseband processing boards, instead of performing network expansion immediately. Figure 1-2 Resource monitoring flowchart
As shown in Figure 1-2, an SPU is overloaded if its CPU usage is 50% to 60%, regardless of other resource usages.
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This flowchart is applicable to most resource monitoring scenarios, except when the system overload is due to an unexpected event, but not a service increase. Unexpected events are not considered in this flowchart. Causes for unexpected events can be located based on their association with various resource bottlenecks. For details on how to locate a resource-related problem, see chapter 4 "Diagnosis of Problems Related to Network Resources."
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2
Network Resource Counters
Various counters are defined to represent the resource usage or load of a UTRAN system. In addition, upper thresholds for these counters are predefined. Identifying the busy hour is a key to accurate counter analysis. There are various methods of identifying the busy hour. The simplest one is to take the hour when the most resources are consumed as the busy hour.
2.1 Uplink Load In a CDMA system, the radio performance of a cell is limited by the received noise. This means that the total received noise (or total received power) in a cell can be used to measure the uplink cell capability. In a WCDMA system, the RTWP value minus the cell background noise is the noise increase that results from a service increase. The noise increase (%) represents the uplink service increase. For example, a 3 dB noise increase corresponds to 50% uplink load and a 6 dB noise increase corresponds to 75% uplink load. Generally, the total uplink received bandwidth is 5 MHz and the background noise is –106 dBm. For the relationship between RTWP, noise increase, and uplink load, see Figure 2-1.
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Figure 2-1 Relationship between RTWP, noise increase, and uplink load
Generally, the uplink load threshold is 75% and the corresponding RTWP is smaller than –100 dBm. The corresponding equivalent number of users (ENU) ratio should be smaller than 75% if the power-based admission decision is based on algorithm 2 (the algorithm for the ENU). If the RTWP value is larger than –100 dBm, the cell is overloaded in the uplink direction. Generally, if a cell is overloaded or the RTWP value is too large, the cell coverage decreases, live service quality declines, or new service requests are rejected. Huawei RNCs support the following RTWP and ENU counters: z
VS.MeanRTWP: mean RTWP in a cell (unit: dBm)
z
VS.MinRTWP: minimum RTWP in a cell (unit: dBm)
z
VS.RAC.UL.EqvUserN: uplink mean ENU on all dedicated channels in a cell
z
UlTotalEqUserNum: maximum ENU that is configured by the ADD UCELLCAC command. UL ENU Ratio = VS.RAC.UL.EqvUserNum/UlTotalEqUserNum
In some areas, the background noise increases to more than –106 dBm due to other interference or hardware faults (for example, poor quality of antennas or feeder connectors). In this case, the VS.MinRTWP counter value (RTWP when the cell carries no traffic) is considered the background noise. If the VS.MinRTWP value is larger than –100 dBm or smaller than –110 dBm in the idle hour for three consecutive days in one week, there are hardware faults or external interference. Locate and rectify the faults. Normally, VS.MeanRTWP is used as the cell capacity indicator. If the VS.MeanRTWP value is higher than –100 dBm (corresponding to a 6 dB noise increase or 75% load) or the uplink ENU ratio is higher than 75% in the busy hour for two or three days in one week, the cell is regarded as heavily loaded. When the cell is heavily loaded, perform capacity expansion operations such as adding a carrier or increasing the UlTotalEqUserNum values.
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2.2 Downlink Load The downlink capacity of a cell is limited by its total available transmit power, which is determined by the base station amplifier and by software settings. When the downlink power is exhausted, the following may occur: z
The cell coverage decreases.
z
The data throughput decreases.
z
The service quality declines.
z
New call requests are rejected.
The amount of consumed downlink power in a cell is not only related to cell traffic (or load), but also related to the user's location and the cell coverage. The larger the cell coverage and the farther the user is located from the cell, the more power is consumed. The heavier the traffic in a cell, the more power is consumed. In a WCDMA system, TCP is defined to measure the downlink total transmit power. For Huawei RNCs, four TCP-associated counters are defined: z
VS.MeanTCP: mean carrier transmit power in a cell
z
VS.MaxTCP: maximum carrier transmit power in a cell
z
VS.MinTCP: minimum carrier transmit power in a cell
z
VS.MeanTCP.NonHS: mean downlink carrier transmit power for non-HSDPA in a cell
VS.MeanTCP is used as the downlink load indicator. If VS.MeanTCP is constantly higher than 85% VS.MaxTCP, the cell is overloaded in the downlink direction. Some live UTRAN networks use hierarchical cell structures with multiple frequency layers. The downlink power settings and the corresponding downlink TCP thresholds vary by carrier. For example, z
If the maximum TCP value is 20 W (43 dBm), the downlink TCP threshold is 17 W (42.3 dBm).
z
If the maximum TCP value is 40 W (46 dBm), the downlink TCP threshold is 34 W (45.3 dBm).
If VS.MeanTCP or VS.MaxTCP exceeds 85% of its threshold in the busy hour for three consecutive days in one week, the cell is regarded as heavily loaded in the uplink direction. Perform capacity expansion operations such as adding a carrier.
2.3 CE Usage CEs are baseband resources provided by NodeBs. One CE corresponds to the resource consumed by a 12.2 kbit/s voice call. If available CE resources are insufficient, a new call request may be rejected. CE resources are managed and shared at the NodeB level (note that 850 MHz and 1900 MHz cells cannot share CEs with each other, because the cells belong to different license groups). The total available CE resources are limited by both the installed hardware and the configured software licenses. If the hardware resources are sufficient and the CE resources are only limited by licenses, you can implement capacity expansion by only upgrading license files.
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For Huawei RANs, various counters are available to monitor CE resources. Once the CE resource usage of a cell is higher than its upper threshold (such as 70%) in the busy hour for two or three days in one week, the cell is overloaded. Add CE resources. For Huawei equipment on the RAN side, the following counters are defined to indicate CE usage: z
VS.LC.ULMean.LicenseGroup: average number of shared UL CEs consumed by a licensed group
z
VS.LC.ULMean.LicenseGroup.Shared: average number of shared UL CEs consumed by an operator
z
VS.LC.ULCreditAvailable.LicenseGroup.Dedicated: number of UL CEs configured for a license group
z
VS.LC.ULCreditAvailable.Shared: configured UL CEs for the shared group
z
VS.LC.DLMean.LicenseGroup: average number of shared DL CEs consumed by a licensed group
z
VS.LC.DLMean.LicenseGroup.Shared: average number of shared DL CEs consumed by an operator
z
VS.LC.DLCreditAvailable.LicenseGroup.Dedicated: average number of DL CEs configured for a license group
z
VS.LC.DLCreditAvailable.Shared: configured DL CEs for the shared group
Separate baseband processing units are used in the uplink and downlink directions of a NodeB, and therefore uplink CE resources are managed independently of downlink CE resources. Uplink and downlink CE usages are defined as: NodeB_UL_CE_MEAN_RATIO = (VS.LC.ULMean.LicenseGroup + VS.LC.ULMean.LicenseGroup.Shared) /(VS.LC.ULCreditAvailable.LicenseGroup.Dedicated + VS.LC.ULCreditAvailable.Shared) NodeB_DL_CE_MEAN_RATIO = (VS.LC.DLMean.LicenseGroup + VS.LC.DLMean.LicenseGroup.Shared)/(VS.LC.DLCreditAvailable.LicenseGroup.Dedicated + VS.LC.DLCreditAvailable.Shared) where z
VS.LC.ULMean.LicenseGroup + VS.LC.ULMean.LicenseGroup.Shared: indicates the mean consumed uplink CE resources in a NodeB license group. (For a NodeB working in the 1900 MHz or 850 MHz band, there are two license groups, one for each carrier.)
z
VS.LC.ULCreditAvailable.LicenseGroup.Dedicated + VS.LC.ULCreditAvailable.Shared: indicates the total number of available uplink CEs in a license group.
z
VS.LC.DLMean.LicenseGroup + VS.LC.DLMean.LicenseGroup.Shared: indicates the mean consumed downlink CE resources in a NodeB license group.
z
VS.LC.DLCreditAvailable.LicenseGroup.Dedicated + VS.LC.DLCreditAvailable.Shared: indicates the total number of available downlink CEs in a license group.
If NodeB_UL_CE_MEAN_RATIO or NodeB_DL_CE_MEAN_RATIO exceeds its threshold (70%) in the busy hour for three consecutive days in one week, the uplink or downlink CE resources need to be expanded. Add baseband processing boards.
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2.4 OVSF Code Usage In a WCDMA system, channels are distinguished by code. For each channel, two types of codes are available: scramble code and orthogonal variable spreading factor (OVSF) code. In the uplink, each user is allocated a unique scramble code. In the downlink, each cell is allocated a unique scramble code. That is, the users in a cell use the same scramble code. Each user in a cell is allocated a unique OVSF code. In a WCDMA cell, data from different users is distinguished based on code division and all user data is transmitted over the same frequency almost at the same time. OVSF codes provide perfect orthogonality, minimizing interference between data from different users. Figure 2-2 shows an OVSF code tree. Figure 2-2 OVSF code tree
A maximum spreading factor (SF) of 256 is supported. For a cell, only an OVSF code tree is available, with sibling codes orthogonal to each other but not with their parent or child codes. As a result, once a code is allocated to a user, neither its parent nor child code can be allocated to any other user. The total OVSF resources are limited. If available OVSF codes are insufficient to implement the desired QoS, a new call request may be rejected. An OVSF code tree can be divided to four codes (SF = 4), 8 codes (SF = 8), 16 codes (SF = 16), or 256 codes (SF = 256). This means that code resources with various SFs can be considered N x equivalent SF = 256 codes. For example, one SF = 8 code is equivalent to thirty-two SF = 256 codes. Based on this equivalence mapping, the OVSF code usage for a user or a cell can be calculated. A Huawei RNC monitors the average code usage of an OVSF code tree based on the number of occupied equivalent SF = 256 codes. The average code usage of an OVSF code tree is indicated by the VS.RAB.SFOccupy counter. OVSF code usages are defined as follows: z
OVSF_Utilization = VS.RAB.SFOccupy/256
z
DCH_OVSF_Utilization = DCH_OVSF_CODE/256
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where DCH_OVSF_CODE = ( + ) x 64 + ( + ) x 32 + ( + ) x 16 + ( + ) x 8 + ( + ) x 4 + ( + ) x 2 + ( + ) A threshold (such as 70%) can be defined for DCH_OVSF_Utilization to judge whether a cell runs out of OVSF codes. If OVSF code resources are insufficient in the busy hour for three consecutive days in one week, perform capacity expansion operations such as adding a carrier or splitting the cell.
2.5 Iub Bandwidth Iub bandwidth needs to be monitored. Based on transport media, Iub transport is classified into ATM transport and IP transport. On either an ATM or IP transport network, Huawei RNCs and NodeBs can monitor the average uplink/downlink load. You can learn the Iub bandwidth usage by comparing the average uplink/downlink load and the total Iub bandwidth. On an ATM transport network, Huawei RNCs and NodeBs can dynamically adjust the bandwidth allowed for each user based on the service QoS requirements and user priorities, and use reverse pressure to increase Iub bandwidth usage efficiency. On an IP transport network, however, Huawei RNCs can use only upper-layer (RLC layer, for example) measures to prevent packet loss over an Iub interface. If calls are frequently rejected due to too many users accessing the network, the Iub bandwidth may be insufficient. If so, increase Iub interfaces as required. For an IP transport network, it is recommended that you do not monitor Iub bandwidth during the implementation phase of the prediction-based monitoring method.
2.6 SPU CPU Load SPUs process all the air interface signaling and transmission interface signaling. They are the boards most likely to be overloaded due to signaling storms. If SPUs are overloaded, new messages are discarded and new call requests are rejected. This will affect end user experience. The load indicator of SPUs is their CPU usage. A Huawei RNC can house multiple SPUs. Each SPUa board contains four CPUs (each represents a subsystem). Each SPUb board contains eight CPUs. A Huawei RNC automatically shares and balances its load between CPUs. If an SPU is overloaded, add SPUs as required. The mean SPU resource usage (SPU CPU load) is indicated by the counter VS.XPU.CPULOAD.MEAN expressed in percentage. It is recommended:
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z
If the SPU CPU usage is over 50% in the busy hour for three consecutive days in one week, add SPUs as required.
z
If the SPU CPU usage is over 60% in the busy hour for three consecutive days in one week, take emergency expansion measures.
2.7 DPU DSP Load The performance of a DPU is measured by its DSP usage. An RNC can house multiple DPU boards. Each DPUb or DPUe board contains several DSPs. Load on an RNC can be dynamically balanced between all its DSPs. The DPU resource usage (the DSP load) is indicated by the counter VS.DSP.UsageAvg (the mean DSP load expressed in percentage). It is recommended that the average DPU DSP usage be not higher than 70%. If the DPU DSP usage is higher than 70% in the busy hour for three consecutive days in one week, expand the DPU capacity.
2.8 Interface Board CPU Load The interface board performance is measured by its CPU usage (for forwarding load or session load). An RNC can house several interface boards. If an interface board is overloaded, re-allocate the load to other interface boards or add an interface board. The interface board resource usage is indicated by the following counters: z
VS.INT.CPULOAD.MEAN: mean CPU usage of an interface board, which is expressed in percentage.
z
VS.INT.TRANSLOAD.RATIO.MEAN: mean forwarding load of an interface board, which is expressed in percentage.
z
Session load = VS.INT.CFG.INTERWORKING.NUM/Number of session setup or release times x 60 x SP
where z
VS.INT.CFG.INTERWORKING.NUM: indicates the number of call setup attempts on an interface board.
z
SP: indicates the measurement period, expressed in minutes.
z
Number of session setup or release times (per second): 500 for a single-core interface board (1000 for the GOUa and FG2a) and 3000 for a multi-core interface board.
It is recommended that you expand the interface board capacity if the mean CPU usage (for forwarding load or session load) is higher than 60% for three consecutive days in one week.
2.9 Common Channels Capacities of common channels, such as PCHs and FACHs, are configurable. If PCH or FACH capacities are insufficient, messages may be lost. A PCH is used to transport paging messages.
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An FACH is used to transport user signaling and a small amount of user data to a UE that is in CELL_FACH state. Common channel analysis needs to be conducted based on monitoring of both PCHs and FACHs. A paging message may be lost if the PCH usage is too high. Paging messages are broadcast across an entire LAC. Therefore, improper LAC planning will contribute to high PCH usage. Two major sources contribute to FACH traffic: PS service state transition and RRC signaling traffic. Based on the default configurations for Huawei RNCs, the PCH usage and FACH usage are calculated as follows: z
PCH usage = VS.UTRAN.AttPaging1/( x 60 x 5/0.01)
z
Usage of an FACH carried on a non-standard SCCPCH = VS.CRNCIubBytesFACH.Tx x 8/[(60 x x 168 x 1/0.01) x VS.PCH.Bandwidth.UsageRate x 6/7 + [60 x x 360 x 1/0.01) x (1- VS.PCH.Bandwidth.UsageRate x 6/7)]
z
Usage of an FACH carried on a standard SCCPCH = VS.CRNCIubBytesFACH.Tx x 8/(60 x x 360 x 1/0.01)
In the preceding formulas, SP indicates the measurement period in seconds. The basic principles for evaluating PCHs are as follows: z
If paging messages are not re-transported, 5% of them will be lost when the PCH usage reaches 60%. It is recommended that you troubleshoot this message loss or replan the LAC.
z
If paging messages are re-transported once or twice, 1% of them will be lost when the PCH usage reaches 70%. It is recommended that you troubleshoot this message loss or replan the LAC.
The basic principle for evaluating FACHs is as follows: If the FACH usage reaches 70%, it is recommended that you optimize specific policies or parameters, or add FACHs as required.
2.10 NodeB CPU Load Main control and transmission board, baseband boards, and extension transmission boards are most likely to be overloaded on a network with many smart terminals. When the CPU on any of the preceding boards is overloaded, the signaling message discard ratio increases and new call requests are rejected. The signaling performance of these boards is measured by their mean CPU usage (VS.BRD.CPULOAD.MEAN) expressed in percentage. It is recommended that you perform capacity expansion (such as splitting the corresponding NodeB or adding a NodeB) if VS.BRD.CPULOAD.MEAN is greater than 60% in the busy hour for three consecutive days in one week.
2.11 WMPT CNBAP Load The WMPT processes signaling messages and manages the resources for other boards.
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If the WMPT is overloaded, a radio link fails to be set up or no response to a radio link setup request is received. This decreases KPIs, such as success ratios of RRC and RAB setup. For Huawei NodeBs, control NBAP (CNBAP) is used to assess the WMPT processing capacity. CNBAP usage
where z
VS.IUB.AttRLSetup: number of Iub interface RL establishment requests for a cell
z
VS.IUB.AttRLAdd: number of Iub interface RL addition requests for a cell
z
VS.IUB.AttRLRecfg: number of Iub interface RL reconfiguration requests for a cell
z
SP: indicates the measurement period, expressed in minutes.
z
CNBAP capacity of a NodeB: depends on the WMPT/WBBP board configuration.
If the CNBAP usage is higher than 60% in the busy hour for three consecutive days in one week, the WMPT is becoming overloaded. Add a baseband board or an extension transmission board, or split the NodeB.
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3
HSPA Related Resources
High Speed Packet Access (HSPA) includes High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA). HSDPA and HSUPA functionalities are part of the WCDMA standard. HSPA uses technologies such as fast scheduling, adaptive modulation, and hybrid automatic repeat request (HARQ) to transport data at high speed. HSPA carries PS data. As conversational services are prioritized over PS data, HSPA uses system resources only after conversational services are served. This chapter looks into how to make more efficient use of system resources by means of HSPA without changing the existing pattern for resource allocation.
3.1 HSDPA 3.1.1 Power Resources Figure 3-1 illustrates how the downlink transmit power of a cell is allocated. The dashed line indicates the total downlink transmit power of a cell. Figure 3-1 Dynamic power resource allocation
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Power for CCH: This portion of power is allocated to common transport channels (CCHs) of the cell such as the broadcast channel, pilot channel, and paging channel. Power margin: This portion of power is not allocated. The power margin is reserved to ensure that the system can remain stable even if the UE position or environment changes. Power for DPCH: This portion of power is allocated to real-time services (voice and video calls) and PS R99 services, and varies with the number and locations of users. RNCs and UEs can adjust power for DPCH based on the power control algorithm. Power for HSPA: This portion of power is allocated to HSDPA and is calculated as follows: HSDPA user power = Maximum cell transmit power – (Power for CCH + Power margin + Power for DPCH) HSPA power schedulers are designed primarily to make the most of available power. In an HSDPA-enabled cell, TCP is still monitored to see if the system is overloaded in the downlink. TCP thresholds for this cell are the same as those for a cell without HSDPA. With HSDPA, downlink power overload affects HSDPA performance before it affects conversational services.
3.1.2 Code Resources HSDPA can share code resources with real-time services. The system can dynamically reallocate OVSF codes to HSDPA services and real-time services based on OVSF code allocation settings (such as the number of codes reserved only for HSDPA and the number of codes that can be shared). These settings can be changed online based on the network plan. When HSDPA is enabled, OVSF code resources are monitored the same way as when HSDPA is not enabled. Note that a high OVSF usage can be reduced by adjusting OVSF code allocation settings (such as the number of codes reserved only for HSDPA and the number of codes that can be shared). Figure 3-2 OVSF code sharing
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3.2 HSUPA 3.2.1 CE Resources HSUPA channels are dedicated channels, and resource consumption of HUSPA services is measured by CE. UL CEs are shared between R99 services and HSUPA services. HSUPA improves user experience and uplink throughput, but also consumes more uplink CE overhead for hybrid automatic repeat requests (HARQ) and soft handovers. This means that uplink CE resources may become a system bottleneck. Therefore, uplink CE usage needs to be monitored when HSUPA is enabled. Huawei NodeBs support dynamic HSUPA CE management.
3.2.2 RTWP Similar to HSDPA, which is designed to make the most of the downlink power, HSUPA is designed to make the most of uplink capacity margin. HSUPA is always authorized to send data until the RTWP rises to 6 dBm. HSUPA provision increases uplink data throughput but also consumes a large amount of uplink RTWP, which is monitored in the same way regardless of whether HSUPA is provisioned. If RTWP overload occurs, rates of HSUPA services must be lowered to ensure QoS of conversational services.
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4 Diagnosis of Problems Related to Network Resources
Diagnosis of Problems Related to Network Resources
The preceding chapters describe the basic methods of monitoring network resources. These methods can be used to resolve most problems caused by high resource usage. In certain scenarios, further analysis is required to determine whether high resource usage is caused by a traffic increase or other exceptions. This chapter describes how to diagnose problems related to network resources. This chapter is intended for experts who have a deep understanding of WCDMA networks.
4.1 Call Blocks in the Basic Call Flow When network resources are running out, KPIs related to system accessibility are most likely to be affected first. Figure 4-1 shows the basic call flowchart where possible block and failure points are marked. For details about the call flow, see 3GPP TS 25.931.
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Figure 4-1 Call flowchart where possible block and failure points are marked
The call flow, which uses a mobile-terminated call as an example, is described as follows: Step 1 The CN sends a paging message to the RNC. Step 2 Upon receipt of the paging message, the RNC broadcasts the message on a PCH. If the PCH is congested, the RNC may drop the message. See block point #1. Step 3 The UE cannot receive the paging message or fails to connect to the network. See failure point # 2. Step 4 After receiving the paging message, the UE sends an RRC connection request to the RNC. Step 5 If the RNC is congested when receiving the RRC connection request, the RNC may drop the request. See block point #3.
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Step 6 If the RNC receives the RRC connection request and does not drop it, the RNC determines whether to accept or reject the request. The request may be rejected due to insufficient resources. See block point #4. Step 7 If the RNC accepts the request, the RNC instructs the UE to set up an RRC connection. The RRC connection setup may fail, the UE does not receive the instruction, or the UE receives the message but finds the configuration information to be incorrect. See failure points #5 and #6. Step 8 After the RRC connection is set up, the UE sends NAS messages to negotiate with the CN about service setup. If the CN determines to set up a service, the CN sends an RAB assignment request to the RNC. Step 9 The RNC accepts or rejects the RAB assignment request based on the resource usage on the RAN side. See block point #7. Step 10 If the RNC accepts the RAB assignment request, the RNC initiates an RB setup process. During the process, the RNC sets up transmission resources over the Iub interface by setting up a radio link (RL) to the NodeB, and sets up channel resources over the Uu interface by sending an RB setup message to the UE. A failure may occur in the RL or RB setup process. See failure points #8 and #9.
4.2 Call Congestion Counters As shown in Figure 4-1, call congestion may occur during paging, RRC connection setup, or RAB establishment. The following describes performance counters and KPIs associated with call congestion rates. For details about call congestion counters, see chapter 5 "Counter Definitions." You can also refer to the BSC6900 UMTS Performance Counter Reference and 3900 Series WCDMA NodeB Performance Counter Reference.
4.2.1 Performance Counters Associated with Paging Loss RNC-level and cell-level performance counters can be used to measure paging loss rates: z
Paging loss (RNC) Counters indicating that RNC-level paging loss ratio are caused by Iu-interface flow control, CPU overload, or RNC-level PCH congestion: VS.RANAP.CsPaging.Loss and VS.RANAP.PsPaging.Loss Iu-interface paging loss ratio (RNC) = [(VS.RANAP.CsPaging.Loss + VS.RANAP.PsPaging.Loss)/ (VS.RANAP.CsPaging.Att + VS.RANAP.PsPaging.Att)] x 100%
z
Paging loss (Cell) Counter indicating that paging requests are discarded due to cell-level PCH congestion: VS.RRC.Paging1.Loss.PCHCong.Cell Iu-interface paging loss ratio (cell) = (VS.RRC.Paging1.Loss.PCHCong.Cell/ VS.UTRAN.AttPaging1) x 100%
4.2.2 Performance Counters Associated with RRC Congestion Rates RRC congestion rates are associated with: Issue Draft A (2012-02-15)
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z
Insufficient uplink power resources: VS.RRC.Rej.ULPower.Cong
z
Insufficient downlink power resources: VS.RRC.Rej.DLPower.Cong
z
Insufficient uplink CE resources: VS.RRC.Rej.UL.CE.Cong
z
Insufficient downlink CE resources: VS.RRC.Rej.DL.CE.Cong
z
Insufficient uplink Iub bandwidth resources: VS.RRC.Rej.ULIUBBand.Cong
z
Insufficient downlink Iub bandwidth resources: VS.RRC.Rej.DLIUBBand.Cong
z
Insufficient downlink code resources: VS.RRC.Rej.Code.Cong
z
Number of RRC requests: VS.RRC.AttConnEstab.Sum
The following is the formula for calculating the paging loss ratio: Vs.RRC.Block.Rate = Toal RRC Rej/ VS.RRC.AttConnEstab.Sum x 100% Where： Toal RRC Rej=< VS.RRC.Rej.ULPower.Cong > + < VS.RRC.Rej.DLPower.Cong > + < VS.RRC.Rej.UL.CE.Cong > + < VS.RRC.Rej.DL.CE.Cong > + < VS.RRC.Rej.ULIUBBand.Cong > + < VS.RRC.Rej.DLIUBBand.Cong > + < VS.RRC.Rej.Code.Cong >
4.2.3 Performance Counters Associated with RAB Congestion Rates RAB congestion rates are associated with: z
z
z
z
z
Insufficient power resources −
VS.RAB.FailEstabCS.ULPower.Cong
−
VS.RAB.FailEstabCS.DLPower.Cong
−
VS.RAB.FailEstabPS.ULPower.Cong
−
VS.RAB.FailEstabPS.DLPower.Cong
Insufficient uplink CE resources −
VS.RAB.FailEstabCS.ULCE.Cong
−
VS.RAB.FailEstabPS.ULCE.Cong
Insufficient downlink CE resources −
VS.RAB.FailEstabCs.DLCE.Cong
−
VS.RAB.FailEstabPs.DLCE.Cong
Insufficient downlink code resources −
VS.RAB.FailEstabCs.Code.Cong
−
VS.RAB.FailEstabPs.Code.Cong
Insufficient downlink Iub bandwidth resources −
VS.RAB.FailEstabCS.DLIUBBand.Cong
−
VS.RAB.FailEstabCS.ULIUBBand.Cong
−
VS.RAB.FailEstabPS.DLIUBBand.Cong
−
VS.RAB.FailEstabPS.ULIUBBand.Cong
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Number of RAB setup requests: VS.RAB.AttEstab.Cell
The following is the formula for calculating the call congestion ratio: VS.RAB.Block.Rate = Total number of congestions due to the preceding causes/VS.RAB.AttEstab.Cell
4.3 Signaling Storms and Solutions In busy hours, a smart terminal makes about 10 more call attempts than a common terminal per call. The additional call attempts generate massive signaling exchange and occupy a large amount of signaling processing resources of the RNC and NodeB on the control plane. Figure 4-2 Process for analyzing signaling storms
Table 4-1 provides solutions to signaling storms. These solutions attempt to reduce signaling loads so that the network capacity does not need to be expanded immediately.
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Table 4-1 Signaling storm causes and solutions UE Behavior
UE Type
Solution
No signaling connection release indication (SCRI)
Nokia, Samsung, or Moto feature phones
Enable the Cell_PCH function to decrease signaling services for these terminals.
SCRI without values indicating causes
iPhone (R6)
Enable the enhanced fast dormancy (EFD) function for RNCs and add international mobile equipment identities (IMEIs) of terminals to the whitelist.
R8 terminals with SCRI carrying values indicating causes
iPhone4 (after R6)
Enable the R8 FD function for RNCs and add terminal IMEIs to the whitelist.
4.4 Resource Analysis Figure 4-3 illustrates the general troubleshooting process for resource usage issues.
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Figure 4-3 General troubleshooting process
Generally, an abnormal KPI initiates a troubleshooting process. Determining the top N cells that may have problems facilitates follow-up troubleshooting. It is recommended to analyze accessibility KPIs to identify the system bottleneck that causes access congestion.
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Figure 4-4 Key points for bottleneck analysis
4.4.2 CE Resource Consumption Analysis Cells under one NodeB share CEs. Common channels have reserved CE resources and signaling is carried on a channel accompanying the DCH. Therefore, CCHs and signaling are considered not to consume CEs. Table 4-2 Number of CEs consumed by different services Service Type
Number of Consumed CEs on the Uplink
Number of Consumed CEs on the Downlink
AMR 12.2 kbit/s
1
1
CS 64 kbit/s
3
2
PS64 kbit/s
3
2
PS128 kbit/s
5
4
PS144 kbit/s
5
4
PS384 kbit/s
10
8
SF32 (HSUPA)
1
N/A
SF16 (HSUPA)
2
N/A
SF4 (HSUPA)
4
N/A
SF4 (HSUPA)
8
N/A
2xSF4 (HSUPA)
16
N/A
2xSF2 (HSUPA)
32
N/A
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Service Type
Number of Consumed CEs on the Uplink
Number of Consumed CEs on the Downlink
2xSF2+2xSF4 (HSUPA)
48
N/A
2xM2+2xM4
64
N/A
CE usage in Table 4-2 assumes that the signaling radio bearer (SRB) over HSUPA feature is enabled. If the SRB is carried on an R99 DCH independently, an extra CE is consumed by the SRB. Therefore, add one CE to the number listed in Table 4-2.
HSDPA services do not consume downlink R99 CEs. HSUPA services and R99 services share uplink CEs. CE congestion or routine CE usage monitoring may trigger CE resource analysis. If the CE resource usage is higher than a preset threshold for a period of time or CE congestion occurs, the CE resources are insufficient and must be increased to ensure system stability.
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Figure 4-5 Process for analyzing CE resource consumption
Cells belonging to the same NodeB share CEs and CE resources consumed by a NodeB must be manually calculated. Check whether CE resource congestion occurs in a resource group or an entire site. If CE resource congestion occurs in a resource group, reallocate CEs between resource groups. If CE resource congestion occurs in an entire site, perform site capacity expansion and reconfigure CEs as required.
4.4.3 Code Resource Usage Analysis Huawei RNCs can reserve codes (for example, five SF = 16 codes) for HSDPA services. If fixed codes are reserved for HSDPA services, code congestion may occur under high traffic. The only solution to code congestion is to add carriers or split sectors. Issue Draft A (2012-02-15)
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In some scenarios, massive signaling exchange on the network occupies a large amount of codes, causing code congestion, power congestion, or CPU overload. In these scenarios, identify root causes and rectify faults rather than expanding capacity. If code congestion occurs, operators can perform the following operations before expanding capacity: z
Decrease the maximum number of PS RABs.
z
Enable code-based load reshuffling (LDR).
z
Decrease the minimum number of codes reserved for HSDPA services.
z
Activate the license for dynamic code allocation on the NodeB.
Thresholds for the preceding code congestion-related operations must be set based on operators' requirements for services quality.
4.4.4 Iub Resource Analysis After IP RAN is introduced, Iub resources no longer need to be monitored. This section is retained to provide a complete solution so that operators can compare solutions provided by different vendors.
If insufficient Iub bandwidth causes congestion, check the Iub bandwidth usage. If the Iub bandwidth usage remains higher than 80% for a certain period, it can be determined that the Iub bandwidth is insufficient. If no more Iub resources are available or the issue is not urgent, decrease PS activity factors so the system admits more users. The activity factor, which is the ratio of actual bandwidth occupied by a user to the allocated bandwidth, is used to estimate the real bandwidth needed in admission. The activity factor can be set on a per-NodeB basis. The default activity factor is 70% for voice services and 40% for PS BE services.
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Figure 4-6 Process for analyzing Iub resources
4.4.5 Power Resource Analysis Power congestion occurs if RTWP and TCP values are larger than preset thresholds. If downlink power congestion occurs, enable the LDR and OLC function. If uplink power is restricted, check whether any interference exists. In most cases, interference rather than traffic increase causes uplink power restriction. If RTWP is larger than –97 dBm over a period of time, analyze root causes and troubleshoot the problem. For high RTWP caused by high traffic (instead of signaling storms): z
Workaround: Enable the LDR and OLC functions.
z
Solution: Add carriers or split cells.
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Figure 4-7 Process for analyzing power resources
Adding carriers is the most efficient solution to insufficient uplink power. If no more carriers are available, add more sites or tilt down antennas to spit cells.
4.4.6 SPU CPU Usage Analysis Among all RNC CPUs, SPU CPUs are the most likely resources to cause system bottlenecks because smart terminals often cause signaling storms on networks. If the SPU CPU usage is higher than the SPU CPU alarming threshold, RNCs will enable the flow control function to discard some RRC setup or paging requests. Ensure that the CPU usage is not higher than the SPU CPU alarming threshold.
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Figure 4-8 Process for analyzing SPU CPUs
If the SPU CPU usage is higher than 50%, advise customers to add SPU boards. If SPU CPU usage is higher than 60%, add SPU boards immediately. Check whether SPU subsystem loads are balanced. If they are unbalanced, adjust load sharing thresholds so that subsystems share loads evenly. In addition, identify root causes for the high CPU usage. If signaling storms occur, check whether system configurations are correct or the transmission link is interrupted. If high traffic causes the high CPU usage, add SPU boards to expand capacity.
4.4.7 DPU DSP and Interface Board CPU Usage Analysis If the DPU DSP or interface board CPUs are overloaded, the RNC will drop some user data. The DPU DSP and interface board loads must be monitored closely. Issue Draft A (2012-02-15)
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Figure 4-9 Process for analyzing DPU DSP and interface board CPU usage
z
If the DPU DSP or interface board CPU usage is higher than 60%, add DPU boards or interface boards.
z
Add hardware for capacity expansion if traffic increase or unbalanced transmission causes the high loads.
4.4.8 PCH Usage Analysis In most cases, PCHs are overloaded because a LAC area covers too many cells. Replan LAC areas to resolve the PCH overload issue.
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Figure 4-10 Process for analyzing PCH usage
4.4.9 FACH Usage Analysis Usually no FACH congestion will occur if the UE state transition switch is turned off. However, the UE state transition switch is turned on by default to transfer low traffic services to FACHs. This saves radio resources but increases traffic on FACHs. Two solutions are available for resolving the FACH congestion issue: z
Decrease values of PS inactive timers to transfer PS services to the CELL_PCH or IDLE state and set up RRC connections on DCHs instead of FACH if DCH resources are sufficient.
z
Add an SCCPCH to carry FACHs
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Figure 4-11 Process for analyzing FACH usage
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5 Counter Definitions
5 Counter Name
Counter Definitions
Counter
Definition
Call drop ratio
Vs.Call.Block.Rate (custom)
Vs.RRC.Block.Rate + ( /( + )) x Vs.Rab.Block.Rate
RRC congestion ratio
Vs.RRC.Block.Rate (custom)
( + + + + + + )/
RAB congestion ratio
Vs.RAB.Block.Rate (custom)
( + + + + + + + + + + + + + )/VS. RAB.AttEstab.Cell
Congestion Counter
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5 Counter Definitions
Counter Name
Counter
Definition
Call attempts
VS.RAB.AttEstab.Cell (custom)
( + + + + + )
R99_TCP_Utiliz ation_Ratio
VS.MeanTCP.NonHS
VS.MeanTCP.NonHS/Configured_Total_Cell_T CP (43 dBm or 46 dBm)
Total_TCP_Utili zation_Ratio
VS.MeanTCP
VS.MeanTCP/Configured_Total_Cell_TCP
Max UL RTWP
VS.MaxRTWP
VS.MaxRTWP
Mean UL RTWP
VS.MeanRTWP
VS.MeanRTWP
Min UL RTWP
VS.MinRTWP
VS.MinRTWP
UL ENU ratio
VS.RAC.UL.EqvUserNum
VS.RAC.UL.EqvUserNum/UlTotalEqUserNum
NODEB_Throughput (custom)
NODEB_Throughput/NODEB_Trans_Cap
Usage Counter Power Usage Counter
IUB Usage Counters IUB BW usage
NODEB_Trans_Cap (custom) NODEB_Trans_ Cap
VS.IPDLTotal.1 VS.IPDLTotal.2
(VS.IPDLTotal.1 + VS.IPDLTotal.2 + VS.IPDLTotal.3 + VS.IPDLTotal.4)
VS.IPDLTotal.3 VS.IPDLTotal.4 NODEB_Throug hput
NODEB_Throughput_DL (custom)
NODEB_Throug hput_DL
VS.IPDLAvgUsed.1
NODEB_Throughput_UL (custom) VS.IPDLAvgUsed.2
MAX(NODEB_Throughput_DL, NODEB_Throughput_UL) (VS.IPDLAvgUsed.1 + VS.IPDLAvgUsed.2 + VS.IPDLAvgUsed.3 + VS.IPDLAvgUsed.4)
VS.IPDLAvgUsed.3 VS.IPDLAvgUsed.4 NODEB_Throug hput_UL
VS.IPULAvgUsed.1 VS.IPULAvgUsed.2
(VS.IPULAvgUsed.1 + VS.IPULAvgUsed.2 + VS.IPULAvgUsed.3 + VS.IPULAvgUsed.4)
VS.IPULAvgUsed.3 VS.IPULAvgUsed.4
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Counter Name
5 Counter Definitions
Counter
Definition
PCH usage
VS.UTRAN.AttPaging1
VS.UTRAN.AttPaging1/(60*60*5/0.01)
FACH usage
VS.CRNCIubBytesFACH.Tx
(1) Utilization of FACH carried on non-standalone SCCPCH
PCH/FACH Usage Counter
VS.PCH.Bandwidth.UsageRate
FACH Utility Ratio = VS.CRNCIubBytesFACH.Tx x 8/((60 x x 168 x 1/0.01) x VS.PCH.Bandwidth.UsageRate x 6/7 + (60 x x 360 x 1/0.01) x (1VS.PCH.Bandwidth.UsageRate x 6/7)) (2) Utilization of FACH carried on standalone SCCPCH FACH Utility Ratio = VS.CRNCIubBytesFACH.Tx x 8/(60 x x 360 x 1/0.01) OVSF Usage Counter OVSF usage
VS.RAB.SFOccupy
VS.RAB.SFOccupy
OVSF usability ratio
VS.RAB.SFOccupy.Ratio
VS.RAB.SFOccupy/256
DCH OVSF ratio
DCH_OVSF_Utilization
[( + ) x 64 + ( + ) x 32 + ( + ) x 16 + ( + ) x 8 + ( + ) x 4 + ( + ) x 2 + ( + )]/256
SPU usage
VS.XPU.CPULOAD.MEAN
VS.XPU.CPULOAD.MEAN
DPU usage
VS.DSP.UsageAvg
VS.DSP.UsageAvg
INT usage
VS.INT.CPULOAD.MEAN
VS.INT.CPULOAD.MEAN
VS.INT.TRANSLOAD.RATIO.MEA N
VS.INT.TRANSLOAD.RATIO.MEAN
VS.BRD.CPULOAD.MEAN
VS.BRD.CPULOAD.MEAN
CPU Usage Counter
NodeB CPU usage
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Counter Name
5 Counter Definitions
Counter
Definition
UL_CE_MEAN _RATIO
VS.LC.ULMean.LicenseGroup
UL_CE_MEAN _REMAIN
VS.LC.ULCreditAvailable.LicenseGro up.Dedicated
(VS.LC.ULMean.LicenseGroup + VS.LC.ULMean.LicenseGroup.Shared)/(VS.LC. ULCreditAvailable.LicenseGroup.Dedicated + VS.LC.ULCreditAvailable.Shared)
Credit Usage Counter VS.LC.ULMean.LicenseGroup.Shared
VS.LC.ULCreditAvailable.Shared UL_CE_MAX_ RATIO UL_CE_MAX_ REMAIN
VS.LC.ULMax.LicenseGroup VS.LC.ULMax.LicenseGroup.Shared VS.LC.ULMax.LicenseGroup
VS.LC.ULCreditAvailable.LicenseGroup.Dedica ted + VS.LC.ULCreditAvailable.Shared VS.LC.ULMean.LicenseGroup VS.LC.ULMean.LicenseGroup.Shared
VS.LC.ULMax.LicenseGroup.Shared (VS.LC.ULMax.LicenseGroup + VS.LC.ULMax.LicenseGroup.Shared)/(VS.LC.U LCreditAvailable.LicenseGroup.Dedicated + VS.LC.ULCreditAvailable.Shared) VS.LC.ULCreditAvailable.LicenseGroup.Dedica ted + VS.LC.ULCreditAvailable.Shared VS.LC.ULMax.LicenseGroup VS.LC.ULMax.LicenseGroup.Shared
DL_CE_MEAN
VS.LC.DLMean.LicenseGroup
DL_CE_MEAN _REMAIN
VS.LC.DLMean.LicenseGroup.Shared VS.LC.DLCreditAvailable.LicenseGro up.Dedicated VS.LC.DLCreditAvailable.Shared
DL_CE_MAX_ RATIO DL_CE_MAX_ REMAIN ULGROUP_CE_ MEAN_Ratio
VS.LC.DLMax.LicenseGroup VS.LC.DLMax.LicenseGroup.Shared VS.LC.DLMax.LicenseGroup
(VS.LC.DLMean.LicenseGroup + VS.LC.DLMean.LicenseGroup.Shared)/(VS.LC. DLCreditAvailable.LicenseGroup.Dedicated + VS.LC.DLCreditAvailable.Shared) VS.LC.ULCreditAvailable.LicenseGroup.Dedica ted + VS.LC.ULCreditAvailable.Shared VS.LC.ULMean.LicenseGroup VS.LC.ULMean.LicenseGroup.Shared
VS.LC.DLMax.LicenseGroup.Shared VS.CE.ULMean.UlGroup VS.CE.ULAvailable.UlGroup
(VS.LC.DLMax.LicenseGroup + VS.LC.DLMax.LicenseGroup.Shared)/(VS.LC.D LCreditAvailable.LicenseGroup.Dedicated + VS.LC.DLCreditAvailable.Shared) VS.LC.DLCreditAvailable.LicenseGroup.Dedica ted + VS.LC.DLCreditAvailable.Shared VS.LC.DLMax.LicenseGroup VS.LC.DLMax.LicenseGroup.Shared VS.CE.ULMean.UlGroup/VS.CE.ULAvailable. UlGroup
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