Concept Guide

Inuencing PVST+ Root Selection............................................................................................................................... 674
Modifying Global PVST+ Parameters.......................................................................................................................... 676
Modifying Interface PVST+ Parameters......................................................................................................................677
Conguring an EdgePort...............................................................................................................................................678
PVST+ in Multi-Vendor Networks................................................................................................................................678
Enabling PVST+ Extend System ID..............................................................................................................................678
PVST+ Sample Congurations..................................................................................................................................... 679
40 Quality of Service (QoS)..........................................................................................................................682
Implementation Information..........................................................................................................................................684
Port-Based QoS Congurations.................................................................................................................................. 684
Setting dot1p Priorities for Incoming Trac.........................................................................................................684
Honoring dot1p Priorities on Ingress Trac..........................................................................................................685
Conguring Port-Based Rate Policing.................................................................................................................. 686
Conguring Port-Based Rate Shaping..................................................................................................................686
Policy-Based QoS Congurations................................................................................................................................687
Classify Trac..........................................................................................................................................................688
Create a QoS Policy................................................................................................................................................. 691
Create Policy Maps..................................................................................................................................................693
DSCP Color Maps..........................................................................................................................................................697
Creating a DSCP Color Map...................................................................................................................................697
Displaying DSCP Color Maps................................................................................................................................. 698
Displaying a DSCP Color Policy Conguration ....................................................................................................698
Enabling QoS Rate Adjustment....................................................................................................................................699
Enabling Strict-Priority Queueing................................................................................................................................699
Weighted Random Early Detection..............................................................................................................................700
Creating WRED Proles...........................................................................................................................................701
Applying a WRED Prole to Trac.........................................................................................................................701
Displaying Default and Congured WRED Proles...............................................................................................701
Displaying WRED Drop Statistics...........................................................................................................................702
Displaying egress–queue Statistics....................................................................................................................... 702
Pre-Calculating Available QoS CAM Space................................................................................................................ 702
Conguring Weights and ECN for WRED ..................................................................................................................703
Global Service Pools With WRED and ECN Settings..........................................................................................704
Conguring WRED and ECN Attributes..................................................................................................................... 705
Guidelines for Conguring ECN for Classifying and Color-Marking Packets......................................................... 706
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class..................................706
Classifying Incoming Packets Using ECN and Color-Marking............................................................................707
Sample conguration to mark non-ecn packets as “yellow” with single trac class......................................708
Applying Layer 2 Match Criteria on a Layer 3 Interface............................................................................................709
Applying DSCP and VLAN Match Criteria on a Service Queue................................................................................710
Classifying Incoming Packets Using ECN and Color-Marking................................................................................... 711
Guidelines for Conguring ECN for Classifying and Color-Marking Packets..........................................................713
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class........................................ 713
Sample conguration to mark non-ecn packets as “yellow” with single trac class............................................ 714
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