Implementing Quality of Service (QoS) Classification and Marking http://www.INE.com

Copyright © 2010 Internetwork Expert, Inc Module 4 Markings Trust Boundaries NBAR Class-Based Marking Pre-Classification QPPB Classifying and Marking on Catalyst Switches Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc Overview Classification and marking is critical on the Catalyst switches since it should take place as close to the source as possible Mapping between Layer 2 and Layer 3 is critical Multilayer switches understand CoS and IP Precedence and DSCP Remember: only trunk links can see CoS markings; QoS must be enabled globally Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc 3560 Examples Enable QoS Globally Switch(config)# mls qos Configuring the trust state on an interface Switch(config-if)# mls qos trust cos Classify based on CoS – if there is no CoS value – use the port default which is set to 0 by default Switch(config-if)# mls qos trust dscp Classify using DSCP – if the switch is marked with a CoS value; the switch maps the CoS value to a DSCP value using the CoS-to-DSCP map Switch(config-if)# mls qos trust ip-precedence Classify using IP Prec– if the switch is marked with a CoS value; the switch maps the CoS value to a DSCP value using the CoS-to-DSCP map Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc 3560 CoS-to-DSCP Map Configuring the CoS-to-DSCP map CoS Value DSCP Value 1 8 2 16 3 24 4 32 5 40 6 48 7 56 mls qos map cos-dscp dscp1...dscp8 show mls qos maps cos-dscp Copyright © 2010 Internetwork Expert, Inc www.INE.com

3560 IP Precedence to DSCP Map Configuring the IP Precedence to DSCP map mls qos map ip-prec-dscp dscp1...dscp8 show mls qos maps ip-prec-dscp Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc 3560 Policed-DSCP Map Configuring the Policed-DSCP map mls qos map policed-dscp dscp-list to mark-down-dscp show mls qos maps policed-dscp Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc 3560 DSCP-to-CoS Map Configuring the DSCP-to-CoS map mls qos map dscp-cos dscp-list to cos show mls qos maps dscp-to-cos Copyright © 2010 Internetwork Expert, Inc www.INE.com

3560 DSCP-to-DSCP Mutation Map Configuring the DSCP-DSCP map mls qos map dscp-mutation dscp-mutation-name in-dscp to out-dscp interface interface-id mls qos trust dscp mls qos dscp-mutation dscp-mutation-name show mls qos maps dscp-mutation Copyright © 2010 Internetwork Expert, Inc www.INE.com

Configuring the CoS Value for an Int Default is 0 mls qos cos {default-cos | override} show mls qos interface Copyright © 2010 Internetwork Expert, Inc www.INE.com

Configuring Trust with Security Have the switch trust…but only a phone! interface interface-id cdp enable mls qos trust cos OR mls qos trust dscp mls qos trust device cisco-phone show mls qos interface Copyright © 2010 Internetwork Expert, Inc www.INE.com

Have the Phone Override the PC The IP Phone can overwrite the markings sent by the PC interface interface-id switchport priority extend cos cos_value Copyright © 2010 Internetwork Expert, Inc www.INE.com

Copyright © 2010 Internetwork Expert, Inc DSCP Transparency Just pass the DSCP settings through no mls qos rewrite ip dscp show mls qos interface Copyright © 2010 Internetwork Expert, Inc www.INE.com

Classification and Marking We will cover VLAN-based QoS in Policing MQC approach to marking is supported based on access lists for classification (if required) Copyright © 2010 Internetwork Expert, Inc www.INE.com