© 2006 Cisco Systems, Inc. All rights reserved.ONT v Introduction to IP QoS Identifying Methods for Implementing QoS
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Methods for Implementing QoS Policy
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Methods for Implementing QoS Policy MethodDescription Legacy CLICLI Configures QoS on interface level Time-consuming MQCCLI Makes configurations modular Best way for QoS fine tuning Cisco AutoQoSApplies a possible QoS configuration to the interfaces Fastest way to implement QoS Cisco SDM QoS wizardApplication for simple QoS configurations
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Legacy CLI
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Legacy CLI Uses the CLI via console and Telnet Traditional method Nonmodular Cannot separate traffic classification from policy definitions Time-consuming and potentially error-prone task Used to augment, fine-tune newer Cisco AutoQoS method
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Legacy CLI Usage Guidelines Build a traffic policy: –Identify the traffic pattern. –Classify the traffic. –Prioritize the traffic. –Select a proper QoS mechanism: Queuing Compression Apply the traffic policy to the interface.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Legacy CLI Example For interactive traffic, CQ and TCP header compression can be used. interface multilink ip address load-interval 30 custom-queue-list 1 ppp multilink ppp multilink fragment-delay 10 ppp multilink interleave multilink-group 1 ip tcp header-compression iphc-format ! queue-list 1 protocol ip 2 tcp 23
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Modular QoS CLI
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Modular QoS CLI A command syntax for configuring QoS policy Reduces configuration steps and time Configures policy, not raw per-interface commands Uniform CLI across major Cisco IOS platforms Uniform CLI structure for all QoS features Separates classification engine from the policy
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Modular QoS CLI Components
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Modular QoS CLI Components
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Modular QoS CLI Components
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Class Maps What traffic do we care about? Each class is identified using a class map. A traffic class contains three major elements: –A case-sensitive name –A series of match commands –An instruction on how to evaluate the match commands if more than one match command exists in the traffic class Class maps can operate in two modes: –Match all: All conditions have to succeed. –Match any: At least one condition must succeed. The default mode is match all.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Configuring Class Maps Enters class-map configuration mode. Specifies the matching strategy. class-map [match-all | match-any] class-map-name router(config)# match any router(config-cmap)# description router(config-cmap)# Use at least one condition to match packets. You should use descriptions in large and complex configurations. The description has no operational meaning. match not match-criteria
© 2006 Cisco Systems, Inc. All rights reserved.ONT v ACLs for Traffic Classification Standard ACL access-list access-list-number {permit | deny | remark} source [mask] router(config)# access-list access-list-number {permit | deny} protocol source source-wildcard [operator port] destination destination-wildcard [operator port] [established] [log] router(config)# match access-group access-list-number router(config-cmap)# Extended ACL Uses an ACL as a match criterion.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Policy Maps What will be done to this traffic? Defines a traffic policy, which configures the QoS features associated with a traffic class previously identified using a class map. A traffic policy contains three major elements: –A case-sensitive name –A traffic class –The QoS policy associated with that traffic class Up to 256 traffic classes can be associated with a single traffic policy. Multiple policy maps can be nested to influence the sequence of QoS actions.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Configuring Policy Maps Enters policy-map configuration mode. Policy maps are identified by a case-sensitive name. policy-map policy-map-name router(config)# class {class-name | class-default} router(config-pmap)# class class-name condition router(config-pmap)# Enters the per-class policy configuration mode by using the name of a previously configured class map. Use the class-default name to configure the policy for the default class. Optionally, you can define a new class map by entering the condition after the name of the new class map. Uses the match any strategy.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Service Policy Where will this policy be implemented? Attaches a traffic policy configured with a policy map to an interface. Service policies can be applied to an interface for inbound or outbound packets.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Attaching Service Policies to Interfaces Attaches the specified service policy map to the input or output interface service-policy {input | output} policy-map-name router(config-if)# class-map HTTP match protocol http ! policy-map PM class HTTP bandwidth 2000 class class-default bandwidth 6000 ! interface Serial0/0 service-policy output PM
© 2006 Cisco Systems, Inc. All rights reserved.ONT v MQC Example Voice traffic needs priority, low delay, and constant bandwidth. Interactive traffic needs bandwidth and low delay.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v MQC Example (Cont.) hostname Office ! class-map VoIP match access-group 100 class-map Application match access-group 101 ! policy-map QoS-Policy class VoIP priority 100 class Application bandwidth 25 class class-default fair-queue ! interface Serial0/0 service-policy output QoS-Policy ! access-list 100 permit ip any any precedence 5 access-list 100 permit ip any any dscp ef access-list 101 permit tcp any host access-list 101 permit tcp any host Classification QoS Policy QoS Policy on Interface Classification
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Basic Verification Commands Displays the class maps show class-map router# show policy-map router# show policy-map interface type number router# Displays the policy maps Displays the applied policy map on the interface
© 2006 Cisco Systems, Inc. All rights reserved.ONT v AutoQoS
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Cisco AutoQoS Automatically discovers applications and provides appropriate QoS treatment Automatically generates initial and ongoing QoS policies Provides high-level business knobs and multidevice and domain automation for QoS Generates intelligent, automatic alerts and summary reports Enables automatic, seamless interoperability among all QoS features and parameters across a network topologyLAN, MAN, and WAN
© 2006 Cisco Systems, Inc. All rights reserved.ONT v The Features of Cisco AutoQoS DiffServ Function Cisco IOS and Catalyst Software QoS Feature Behavior ClassificationNBAR DSCP, portClassifies VoIP based on packet attributes or port trust MarkingClass-based markingSets Layer 2 and Layer 3 attributes to categorize packets into a class Congestion management Percentage-based LLQ, WRR Provides Expedited Forwarding treatment to voice and best-effort treatment to data ShapingClass-based shaping or FRTS Shapes to CIR to prevent burst and smooth traffic to configured rate Link efficiency mechanism Header compressionReduces the VoIP bandwidth requirement Link efficiency mechanism Link Fragmentation and Interleaving Reduces jitter experienced by voice packets
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Cisco AutoQoS Usage Guidelines Make sure that: –CEF is enabled. –NBAR is enabled. –Correct bandwidth statement is configured on the interface. Finally, enable Cisco AutoQoS on the interface.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Cisco AutoQoS Example Enable Cisco AutoQoS on relevant devices (such as LAN switches and WAN routers) that need to perform QoS.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Cisco AutoQoS Example (Cont.) interface Serial1/3 ip cef bandwidth 1540 ip address auto qos voip IP CEF and Bandwidth AutoQoS for VoIP Traffic Recognized by NBAR
© 2006 Cisco Systems, Inc. All rights reserved.ONT v SDM QoS Wizard
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Cisco SDM QoS Wizard Cisco SDM is an intuitive, web-based device management tool for easy and reliable deployment and management of Cisco IOS routers. Cisco SDM provides wizards for: –Firewall and NAT –Intrusion prevention –IPsec VPNs –QoS –Routing
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Features Cisco SDM QoS wizard provides: –QoS policing –NBAR –Traffic monitoring Supported and preinstalled on Cisco 850, 870, 1800, 2800, and 3800 Cisco Integrated Services Routers Supported on devices 830, 1700, 2600 XM, 2800, 3700, 7200 VXR, and 7301
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Getting Started with Cisco SDM
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Create QoS Policy
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Wizard
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Interface Selection
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Policy Generation
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary (Cont.)
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary (Cont.)
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary (Cont.)
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary (Cont.)
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Command Delivery Status
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Status A B
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Implementation Methods Compared
© 2006 Cisco Systems, Inc. All rights reserved.ONT v QoS Implementation Methods Compared Legacy CLIMQC Cisco AutoQoS Cisco SDM QoS Wizard Ease of usePoorEasierSimple Ability to fine-tune OKVery goodLimited Time to implement LongestAverageShortestShort ModularityPoorExcellent Very good
© 2006 Cisco Systems, Inc. All rights reserved.ONT v Summary There are four methods for implementing QoS: legacy CLI, MQC, Cisco AutoQoS, and Cisco SDM QoS wizard. CLI QoS configuration can be complex and in many cases requires learning different syntax for different QoS mechanisms. MQC separates the classification of network traffic from the definition of the QoS policy. Cisco AutoQoS is used to automatically implement a set of QoS policies on a router or a switch. Cisco SDM QoS wizard provides a GUI to ease QoS configuration. MQC is the recommended manual approach to configure QoS. MQC reduces configuration steps and time compared to the legacy approach.
© 2006 Cisco Systems, Inc. All rights reserved.ONT v