Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - QUALITY OF SERVICE CONFIGURATION GUIDE 2010-09-22 Configuration Manual page 19

List of Figures
Part 1
Chapter 1
Part 2
Chapter 4
Part 3
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter 10
Chapter 11
Copyright © 2010, Juniper Networks, Inc.
QoS on the E Series Router
Quality of Service Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 1: Traffic Flow Through an E Series Router . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Classifying, Queuing, and Dropping Traffic
Configuring Dropping Behavior with RED and WRED . . . . . . . . . . . . . . . . . . . 25
Figure 2: Packets Dropped as Queue Length Increases . . . . . . . . . . . . . . . . . . . . . 26
Figure 3: Color-Blind RED Drop Profile with Colorless Queue Profile . . . . . . . . . . . 29
Figure 4: Color-Blind RED Drop Profile with Color-Sensitive Queue Profile . . . . . 30
Figure 5: Different Treatment of Colored Packets . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 6: Defining Different Drop Behavior for Each Queue . . . . . . . . . . . . . . . . . . 33
Figure 7: WRED and Dynamic Queue Thresholding . . . . . . . . . . . . . . . . . . . . . . . . 35
Scheduling and Shaping Traffic
QoS Scheduler Hierarchy Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Figure 8: QoS Scheduler Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Configuring Rates and Weights in the Scheduler Hierarchy . . . . . . . . . . . . . . 51
Figure 9: Port Shaping on an Ethernet Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 10: Hierarchical Assured Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Configuring Strict-Priority Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Figure 11: Sample Strict-Priority Scheduling Hierarchy . . . . . . . . . . . . . . . . . . . . . . 58
Figure 12: True Strict-Priority Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Figure 13: Relative Strict-Priority Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Figure 14: Tuning Latency on Strict-Priority Queues . . . . . . . . . . . . . . . . . . . . . . . . 63
Figure 15: Sample Strict-Priority Scheduling Hierarchy . . . . . . . . . . . . . . . . . . . . . 64
Figure 16: Sample Relative Strict-Priority Scheduler Hierarchy . . . . . . . . . . . . . . . 66
Shared Shaping Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Figure 17: Implicit Constituent Selection for Compound Shared Shaper: Mixed
Interface Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Configuring Simple Shared Shaping of Traffic . . . . . . . . . . . . . . . . . . . . . . . . 75
Figure 18: Simple Shared Shaping over ATM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Figure 19: Simple Shared Shaping over Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Figure 20: VP Shared Shaping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Figure 21: Hierarchical Simple Shared Shaping over Ethernet . . . . . . . . . . . . . . . . 82
Configuring Variables in the Simple Shared Shaping Algorithm . . . . . . . . . 85
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