xsdenied07
2010-06-16, 06:29 PM
W-PS Service Problem Optimization Guide.
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Table of Contents
1 Introduction ......................................................................................................................... 10
2 Evaluation of PS Throughput Problems ........................................................................... 11
3 Data Collection .................................................................................................................. 14
3.1 Traffic Statistics ................................................................................................................................ 15
3.2 DT/CQT ............................................................................................................................................ 15
3.3 Others ................................................................................................................................................ 16
4 Analysis of Traffic Statistics Data ...................................................................................... 19
4.1 Analysis of Traffic Statistics for Throughput Problems ..................................................................... 20
4.1.1 Traffic Statistics Indexes Related to Throughput ...................................................................... 20
4.1.2 Generic Analysis Flow .............................................................................................................. 23
5 Analysis of DT/CQT Data .................................................................................................. 31
5.1 Access Failure ................................................................................................................................... 32
5.1.1 Originating PS Service by UE Directly .................................................................................... 32
5.1.2 UE as the Modem of PC ........................................................................................................... 33
5.2 Disconnection of Service Plane .......................................................................................................... 39
5.2.1 Analyze Problems at RNA Side ................................................................................................ 40
5.2.2 Analyzing Problems at CN Side ................................................................................................ 46
5.3 Poor Performance of Data Tranfer ..................................................................................................... 48
5.3.1 Checking Alarms ....................................................................................................................... 49
5.3.2 Comparing Operations and Analyzing Problem........................................................................ 50
5.3.3 Analyzing Poor Performance of Data Transfer by DCH ........................................................... 51
5.3.4 Analyzing Poor Performance of Data Transfer by HSDPA at RAN Side .................................. 56
5.3.5 Analyzing Poor Performance of Data Transfer at CN Side ....................................................... 75
5.4 Interruption of Data Transfer.............................................................................................................. 78
5.4.1 Analzying Interruption of Data Transfer ................................................................................... 78
5.4.2 Analyzing HSDPA Interruption of Data Transfer ...................................................................... 80
6 Cases ................................................................................................................................... 85
6.1 Cases at RAN Side ............................................................................................................................. 86
6.1.1 Call Drop due to Subscriber Congestion (Iub Resource Restriction) ........................................ 86
6.1.2 Uplink PS64k Service Rate Failing to Meet Acceptance Requirements in a Test (Air Interface Problem) ........................................................................................................................................... 86
6.1.3 Statistics and Analysis of Ping Packet Delay in Services of Different Types ........................... 87
6.1.4 Low Rate of HSDPA Data Transfer due to Over Low Pilot Power ........................................... 88
6.1.5 Unstable HSDPA Rate due to Overhigh Receiving Power of Data Card .................................. 89
6.1.6 Impossible Maximum HSDPA Rate due to Over large Radius of Cell ..................................... 90
6.1.7 Decline of Total Throughput in Cell due to AAL2PATH Bandwidth larger than Actual Physical Bandwidth ......................................................................................................................................... 91
6.2 Cases at CN Side ............................................................................................................................... 93
6.2.1 Low FTP Downloading Rate due to Over Small TCP Window on Server TCP ....................... 93
6.2.2 Simultaneous Uploading and Downloading .............................................................................. 95
6.2.3 Decline of Downloading Rate of Multiple UEs ........................................................................ 96
6.2.4 Unstable PS Rate (Loss of IP Packets) ...................................................................................... 97
6.2.5 Unstable PS Rate of Single Thread in Commercial Deployment (Loss of IP Packets) ............. 99
6.2.6 Unavailable Streaming Service for a Subscriber ..................................................................... 100
6.2.7 Unavailable PS Services due to Firewall of Laptop ................................................................ 100
6.2.8 Low PS Service Rate in Presentation Occasion ...................................................................... 100
6.2.9 Abnormal Ending after Long-time Data Transfer by FTP ...................................................... 101
6.2.10 Analysis of Failure in PS Hanodver Between 3G Network and 2G Network ....................... 106
7 Summary ........................................................................................................................... 110
8 Appendix .......................................................................................................................... 111
8.1 Transport Channel of PS Data .......................................................................................................... 111
8.2 Theoretical Rates at Each Layer ....................................................................................................... 112
8.2.2 TCP/IP Layer .......................................................................................................................... 113
8.2.3 RLC Layer .............................................................................................................................. 113
8.2.4 Retransmission Overhead ....................................................................................................... 113
8.2.5 MAC-HS Layer ....................................................................................................................... 114
8.3 Bearer Methods of PS Services ........................................................................................................ 114
8.3.1 DCH ....................................................................................................................................... 114
8.3.2 HSDPA ................................................................................................................................... 115
8.3.3 CCH ....................................................................................................................................... 115
8.4 Description of HSDPA Algorithms and Parameters ......................................................................... 115
8.4.1 Code Resource Configuration ................................................................................................. 115
8.4.2 HS-PDSCH MPO Instant ........................................................................................................ 120
8.4.3 HSDPA UE Category .............................................................................................................. 121
8.4.4 HS-DPCCH Power Control .................................................................................................... 122
8.5 Method for Modifying TCP Receive Window ................................................................................. 126
8.5.1 Tool Modification ................................................................................................................... 126
8.5.2 Regedit Modification .............................................................................................................. 126
8.6 Method for Modifying MTU ............................................................................................................ 127
8.6.1 Tool Modification ................................................................................................................... 127
8.6.2 Regedit Modification .............................................................................................................. 128
8.7 Confirming APN and Rate in Activate PDP Context Request Message ........................................... 128
8.7.2 Traffic Class ............................................................................................................................ 129
8.7.3 Maximum Rate and Guaranteed Rate ..................................................................................... 129
8.7.4 APN........................................................................................................................................ 130
8.8 APN Effect ...................................................................................................................................... 131
8.8.1 Major Effect ............................................................................................................................ 131
8.8.2 Method for Naming APN ........................................................................................................ 131
8.8.3 APN Configuration ................................................................................................................. 131
8.9 PS Tools .......................................................................................................................................... 131
8.9.1 TCP Receive Window and MTU Modification Tools ............................................................. 131
8.9.2 Sniffer .................................................................................................................................... 132
8.9.3 Common Tool to Capture Packet: Ethereal ............................................................................. 132
8.9.4 HSDPA Test UE ...................................................................................................................... 133
8.10 Analysis of PDP Activation ............................................................................................................ 133
9303
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Password:-n/a
Table of Contents
1 Introduction ......................................................................................................................... 10
2 Evaluation of PS Throughput Problems ........................................................................... 11
3 Data Collection .................................................................................................................. 14
3.1 Traffic Statistics ................................................................................................................................ 15
3.2 DT/CQT ............................................................................................................................................ 15
3.3 Others ................................................................................................................................................ 16
4 Analysis of Traffic Statistics Data ...................................................................................... 19
4.1 Analysis of Traffic Statistics for Throughput Problems ..................................................................... 20
4.1.1 Traffic Statistics Indexes Related to Throughput ...................................................................... 20
4.1.2 Generic Analysis Flow .............................................................................................................. 23
5 Analysis of DT/CQT Data .................................................................................................. 31
5.1 Access Failure ................................................................................................................................... 32
5.1.1 Originating PS Service by UE Directly .................................................................................... 32
5.1.2 UE as the Modem of PC ........................................................................................................... 33
5.2 Disconnection of Service Plane .......................................................................................................... 39
5.2.1 Analyze Problems at RNA Side ................................................................................................ 40
5.2.2 Analyzing Problems at CN Side ................................................................................................ 46
5.3 Poor Performance of Data Tranfer ..................................................................................................... 48
5.3.1 Checking Alarms ....................................................................................................................... 49
5.3.2 Comparing Operations and Analyzing Problem........................................................................ 50
5.3.3 Analyzing Poor Performance of Data Transfer by DCH ........................................................... 51
5.3.4 Analyzing Poor Performance of Data Transfer by HSDPA at RAN Side .................................. 56
5.3.5 Analyzing Poor Performance of Data Transfer at CN Side ....................................................... 75
5.4 Interruption of Data Transfer.............................................................................................................. 78
5.4.1 Analzying Interruption of Data Transfer ................................................................................... 78
5.4.2 Analyzing HSDPA Interruption of Data Transfer ...................................................................... 80
6 Cases ................................................................................................................................... 85
6.1 Cases at RAN Side ............................................................................................................................. 86
6.1.1 Call Drop due to Subscriber Congestion (Iub Resource Restriction) ........................................ 86
6.1.2 Uplink PS64k Service Rate Failing to Meet Acceptance Requirements in a Test (Air Interface Problem) ........................................................................................................................................... 86
6.1.3 Statistics and Analysis of Ping Packet Delay in Services of Different Types ........................... 87
6.1.4 Low Rate of HSDPA Data Transfer due to Over Low Pilot Power ........................................... 88
6.1.5 Unstable HSDPA Rate due to Overhigh Receiving Power of Data Card .................................. 89
6.1.6 Impossible Maximum HSDPA Rate due to Over large Radius of Cell ..................................... 90
6.1.7 Decline of Total Throughput in Cell due to AAL2PATH Bandwidth larger than Actual Physical Bandwidth ......................................................................................................................................... 91
6.2 Cases at CN Side ............................................................................................................................... 93
6.2.1 Low FTP Downloading Rate due to Over Small TCP Window on Server TCP ....................... 93
6.2.2 Simultaneous Uploading and Downloading .............................................................................. 95
6.2.3 Decline of Downloading Rate of Multiple UEs ........................................................................ 96
6.2.4 Unstable PS Rate (Loss of IP Packets) ...................................................................................... 97
6.2.5 Unstable PS Rate of Single Thread in Commercial Deployment (Loss of IP Packets) ............. 99
6.2.6 Unavailable Streaming Service for a Subscriber ..................................................................... 100
6.2.7 Unavailable PS Services due to Firewall of Laptop ................................................................ 100
6.2.8 Low PS Service Rate in Presentation Occasion ...................................................................... 100
6.2.9 Abnormal Ending after Long-time Data Transfer by FTP ...................................................... 101
6.2.10 Analysis of Failure in PS Hanodver Between 3G Network and 2G Network ....................... 106
7 Summary ........................................................................................................................... 110
8 Appendix .......................................................................................................................... 111
8.1 Transport Channel of PS Data .......................................................................................................... 111
8.2 Theoretical Rates at Each Layer ....................................................................................................... 112
8.2.2 TCP/IP Layer .......................................................................................................................... 113
8.2.3 RLC Layer .............................................................................................................................. 113
8.2.4 Retransmission Overhead ....................................................................................................... 113
8.2.5 MAC-HS Layer ....................................................................................................................... 114
8.3 Bearer Methods of PS Services ........................................................................................................ 114
8.3.1 DCH ....................................................................................................................................... 114
8.3.2 HSDPA ................................................................................................................................... 115
8.3.3 CCH ....................................................................................................................................... 115
8.4 Description of HSDPA Algorithms and Parameters ......................................................................... 115
8.4.1 Code Resource Configuration ................................................................................................. 115
8.4.2 HS-PDSCH MPO Instant ........................................................................................................ 120
8.4.3 HSDPA UE Category .............................................................................................................. 121
8.4.4 HS-DPCCH Power Control .................................................................................................... 122
8.5 Method for Modifying TCP Receive Window ................................................................................. 126
8.5.1 Tool Modification ................................................................................................................... 126
8.5.2 Regedit Modification .............................................................................................................. 126
8.6 Method for Modifying MTU ............................................................................................................ 127
8.6.1 Tool Modification ................................................................................................................... 127
8.6.2 Regedit Modification .............................................................................................................. 128
8.7 Confirming APN and Rate in Activate PDP Context Request Message ........................................... 128
8.7.2 Traffic Class ............................................................................................................................ 129
8.7.3 Maximum Rate and Guaranteed Rate ..................................................................................... 129
8.7.4 APN........................................................................................................................................ 130
8.8 APN Effect ...................................................................................................................................... 131
8.8.1 Major Effect ............................................................................................................................ 131
8.8.2 Method for Naming APN ........................................................................................................ 131
8.8.3 APN Configuration ................................................................................................................. 131
8.9 PS Tools .......................................................................................................................................... 131
8.9.1 TCP Receive Window and MTU Modification Tools ............................................................. 131
8.9.2 Sniffer .................................................................................................................................... 132
8.9.3 Common Tool to Capture Packet: Ethereal ............................................................................. 132
8.9.4 HSDPA Test UE ...................................................................................................................... 133
8.10 Analysis of PDP Activation ............................................................................................................ 133
9303
Add Reputation and say thanks.........:p:p:p:p