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Cisco IOS Software Releases 12.2 T

Frame Relay Voice-Adaptive Traffic Shaping

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Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Contents

Prerequisites for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Restrictions for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Information About Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Benefits of Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Frame Relay Voice-Adaptive Traffic Shaping

Frame Relay Voice-Adaptive Fragmentation

How to Configure Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Configuring Class Policy for the Priority Queue and Bandwidth Queues

Configuring Frame Relay Voice-Adaptive Traffic Shaping Using the Class-Default Class

Configuring a Map Class for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Enabling Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation on the Interface

Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Configuration Examples for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Examples

Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

frame-relay fragmentation voice-adaptive

shape fr-voice-adapt

show frame-relay pvc

show policy-map

show policy-map interface


Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

The Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation feature helps ensure voice quality by adjusting the rate of traffic and activating fragmentation on the basis of the presence of voice on the permanent virtual circuit (PVC). Frame Relay voice-adaptive traffic shaping enables a PVC to adjust the rate of traffic if packets are detected in the priority queue or if H.323 call setup signaling packets are detected. Frame Relay voice-adaptive fragmentation allows fragmentation to be activated when priority-queue or H.323 signaling packets are detected. When priority-queue traffic and signaling packets are not present, Frame Relay voice-adaptive fragmentation allows fragmentation to be deactivated.

Feature Specifications for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Feature History
 
Release
Modification

12.2(15)T

This feature was introduced.

Supported Platforms

Cisco 1700 series, Cisco 2600 series, Cisco 3600 series, Cisco 3700 series, Cisco 4500, Cisco 7200 series, Cisco 7400 series, Cisco 7500 series (without Versatile Interface Processor.)


Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Contents

•Prerequisites for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Restrictions for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Information About Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•How to Configure Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Configuration Examples for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Additional References

•Command Reference

Prerequisites for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Prerequisites for Frame Relay Voice-Adaptive Traffic Shaping

•Traffic shaping and low latency queueing must be configured using the Modular QoS CLI (MQC).

Prerequisites for Frame Relay Voice-Adaptive Fragmentation

•End-to-end fragmentation must be configured in a map class or on the interface.

•Frame Relay traffic shaping or traffic shaping using the MQC must be configured. If end-to-end fragmentation is configured on the interface, traffic shaping must be configured using the MQC.

•Low latency queueing must be configured.

•End-to-end fragmentation must be configured on the peer router. Although the peer router may not see the expected fragmented packets from the router doing voice-adaptive fragmentation, the peer will be able to handle large unfragmented packets in addition to fragmented packets.

Restrictions for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

The feature supports FRF.12 fragmentation only. Neither FRF.11 Annex C nor Cisco proprietary fragmentation is supported.

Information About Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Benefits of Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Frame Relay Voice-Adaptive Traffic Shaping

•Frame Relay Voice-Adaptive Fragmentation

Benefits of Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Before the introduction of this new feature, Frame Relay adaptive shaping could be used to reduce the sending rate when a network was congested. Because the adaptive shaping mechanism was triggered by network congestion, voice traffic might already have been delayed by the time the sending rate was reduced. The Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation feature helps to ensure voice quality by adjusting the rate of traffic based on the presence of voice on the PVC.

Frame Relay voice-adaptive traffic shaping and fragmentation

•Prevents delay of voice packets when network congestion occurs by reducing the traffic rate to the minimum committed information rate (minCIR) and turning on fragmentation when voice packets are present on a PVC.

•Maximizes utilization of the PVC by increasing the traffic rate to committed information rate (CIR) when voice packets are not present.

•Reduces CPU utilization by turning off fragmentation when there are no voice packets present.

Frame Relay Voice-Adaptive Traffic Shaping

Frame Relay voice-adaptive traffic shaping enables a router to reduce the PVC sending rate to the minCIR whenever packets (usually voice) are detected in the low latency queueing priority queue or H.323 call setup signaling packets are present. When there are no packets in the priority queue and signaling packets are not present for a configured period of time, the router increases the PVC sending rate from minCIR to CIR to maximize throughput.

Note Although the priority queue is generally used for voice traffic, Frame Relay voice-adaptive traffic shaping will respond to any packets (voice or data) in the priority queue.

Frame Relay voice-adaptive traffic shaping can be used at the same time as other types of adaptive traffic shaping. For example, if both Frame Relay voice-adaptive traffic shaping and adaptive shaping based on interface congestion are configured, the router will reduce the sending rate to minCIR if there are packets in the priority queue or the interface queue size exceeds the configured threshold.

Frame Relay voice-adaptive traffic shaping can be used in conjunction with or independently of voice-adaptive fragmentation.

Frame Relay Voice-Adaptive Fragmentation

Frame Relay voice-adaptive fragmentation enables a router to fragment large data packets whenever packets (usually voice) are detected in the low latency queueing priority queue or H.323 call setup signaling packets are present. When there are no packets in the priority queue for a configured period of time and signaling packets are not present, fragmentation is stopped.

Note Although the priority queue is generally used for voice traffic, Frame Relay voice-adaptive fragmentation will respond to any packets (voice or data) in the priority queue.

Frame Relay voice-adaptive fragmentation can be used in conjunction with or independent of voice-adaptive traffic shaping.

To use voice-adaptive fragmentation, you must also have end-to-end fragmentation configured in a map class or on the interface.

How to Configure Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

The following tasks describe how to configure low latency queueing in addition to Frame Relay voice-adaptive traffic shaping and fragmentation.

Note The following tasks enable both Frame Relay voice-adaptive traffic shaping and fragmentation. These two features can also be used separately. If you choose to use voice-adaptive fragmentation by itself, you can configure either MQC traffic shaping (as in the tasks that follow) or Frame Relay traffic shaping. If you use Frame Relay traffic shaping, end-to-end fragmentation must be configured in a map class.

•Configuring Class Policy for the Priority Queue and Bandwidth Queues (required)

•Configuring Frame Relay Voice-Adaptive Traffic Shaping Using the Class-Default Class (required)

•Configuring a Map Class for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation (required)

•Enabling Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation on the Interface (required)

•Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation (optional)

Configuring Class Policy for the Priority Queue and Bandwidth Queues

Perform this task to configure a policy map for the priority class and other classes.

SUMMARY STEPS

1. enable

2. configure terminal

3. policy-map policy-map

4. class class-name

5. priority bandwidth-kbps

6. exit

7. class class-name

8. bandwidth bandwidth-kbps

9. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

policy-map policy-map

Example:

Router(config)# policy-map FR-VATS

Specifies the name of the policy map to be created or modified.

•Use this command to define the queueing policy for the priority queue.

Step 4 

class class-name

Example:

Router(config-pmap)# class VOICE

Specifies the name of a class to be created and included in the service policy.

•The class name that you specify in the policy map defines the characteristics for that class and its match criteria as configured using the class-map command.

Step 5 

priority bandwidth-kbps

Example:

Router(config-pmap-c)# priority 10

Creates a strict priority class and specifies the amount of bandwidth, in kbps, to be assigned to the class.

Step 6 

exit

Example:

Router(config-pmap-c)# exit

Returns to policy map configuration mode.

Step 7 

class class-name

Example:

Router(config-pmap)# class DATA

Specifies the name of a class to be created and included in the service policy.

•The class name that you specify in the policy map defines the characteristics for that class and its match criteria as configured using the class-map command.

Step 8 

bandwidth bandwidth-kbps

Example:

Router(config-pmap-c)# bandwidth 10

Specifies the amount of bandwidth to be assigned to the class, in kbps or as a percentage of the available bandwidth. Bandwidth must be specified in kbps or as a percentage consistently across classes. (Bandwidth of the priority queue must be specified in kbps.)

Step 9 

end

Example:

Router(config-pmap-c)# end

Exits to privileged EXEC mode.

Configuring Frame Relay Voice-Adaptive Traffic Shaping Using the Class-Default Class

Perform the following task to configure the shaping policy, including Frame Relay voice-adaptive traffic shaping, in the class-default class.

SUMMARY STEPS

1. enable

2. configure terminal

3. policy-map policy-map

4. class class-default

5. shape [average | peak] mean-rate [[burst-size] [excess-burst-size]]

6. shape adaptive mean-rate-lower-bound

7. shape fr-voice-adapt [deactivation seconds]

8. service-policy policy-map-name

9. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

policy-map policy-map

Example:

Router(config)# policy-map SHAPE

Specifies the name of the policy map to be created or modified.

•Use this command to define the shaping policy.

Step 4 

class class-default

Example:

Router(config-pmap)# class class-default

Specifies the default class so that you can configure or modify its policy.

Step 5 

shape [average | peak] mean-rate [[burst-size] [excess-burst-size]]

Example:

Router(config-pmap-c)# shape average 60000

Shapes traffic to the indicated bit rate according to the algorithm specified.

Step 6 

shape adaptive mean-rate-lower-bound

Example:

Router(config-pmap-c)# shape adaptive 30000

(Optional) Configures a Frame Relay interface or a point-to-point subinterface to estimate the available bandwidth while traffic shaping is active.

Step 7 

shape fr-voice-adapt [deactivation seconds]

Example:

Router(config-pmap-c)# shape fr-voice-adapt deactivation 10

Enables Frame Relay voice-adaptive traffic shaping.

Step 8 

Service-policy policy-map-name

Example:

Router(config-pmap-c)#service-policy FR-VATS

Specifies the name of a policy map to be used as a matching criterion (for nesting traffic policies [hierarchical traffic policies] within one another).

•Use this command to attach the policy map for the priority queue and bandwidth queues (the child policies) to the shaping policy (the parent policy).

Step 9 

end

(Optional) Exits to privileged EXEC mode.

Configuring a Map Class for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Perform the following task to configure a map class for Frame Relay voice-adaptive traffic shaping and fragmentation.

SUMMARY STEPS

1. enable

2. configure terminal

3. map-class frame-relay map-class-name

4. frame-relay fragment fragment_size

5. service-policy output policy-map-name

6. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

map-class frame-relay map-class-name

Example:

Router(config)# map-class frame-relay VOICE-CLASS

Specifies the name of a Frame Relay map class that is to be created or modified.

Step 4 

frame-relay fragment fragment_size

Example:

Router(config-map-class)# frame-relay fragment 80

Enables Frame Relay fragmentation.

Note For voice-adaptive fragmentation to work, fragmentation must be enabled here in a map class, or it can be configured directly on the interface.

Step 5 

service-policy output policy-map-name

Example:

Router(config-map-class)# service-policy output SHAPE

Attaches a policy map to an output interface, to be used as the service policy for that interface.

•Use this command to attach the shaping policy to the map class.

Step 6 

end

Example:

Router(config-map-class)# end

Exits to privileged EXEC mode.

Enabling Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation on the Interface

Perform the following task to enable Frame Relay voice-adaptive traffic shaping and fragmentation on the interface.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface type number

4. encapsulation frame-relay

5. frame-relay fragmentation voice-adaptive [deactivation seconds]

6. frame-relay fragment fragment-size end-to-end

7. frame-relay interface-dlci dlci [ietf | cisco] [voice-cir cir]

8. class name

9. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface type number

Example:

Router(config)# interface serial0

Specifies the interface to be configured and enters interface configuration mode.

Step 4 

encapsulation frame-relay

Example:

Router(config-if)# encapsulation frame-relay

Enables Frame Relay encapsulation.

Step 5 

frame-relay fragmentation voice-adaptive [deactivation seconds]

Example:

Router(config-if)# frame-relay fragmentation voice-adaptive deactivation 50

Enables Frame Relay voice-adaptive fragmentation.

Step 6 

frame-relay fragment fragment-size end-to-end

Example:

Router(config-if)# frame-relay fragment 80 end-to-end

Enables Frame Relay fragmentation on an interface.

Note For voice-adaptive fragmentation to work, fragmentation must be enabled here on the interface, or it can be configured in a map class.

•When fragmentation is enabled on an interface, all PVCs on the main interface and its subinterfaces will have fragmentation enabled with the same configured fragment size.

•To maintain low latency and low jitter for priority queue traffic, configure the fragment size to be greater than the largest high-priority frame that would be expected.

Step 7 

frame-relay interface-dlci dlci [ietf | cisco] [voice-cir cir]

Example:

Router(config-if)#

Specifies a PVC to be configured.

Step 8 

class name

Example:

Router(config-fr-dlci)#

Associates a map class with a specified data-link connection identifier (DLCI).

•Use this command to assign the map class that was configured with Frame Relay voice-adaptive traffic shaping to the PVC.

Step 9 

end

Example:

Router(config-fr-dlci)# end

Exits to privileged EXEC mode.

Step 10 


 

Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

Perform this task to verify the configuration and operation of Frame Relay voice-adaptive traffic shaping and fragmentation.

SUMMARY STEPS

1. enable

2. show policy-map [policy-map]

3. show policy-map interface interface-name [dlci dlci] [input | output]

4. show frame-relay pvc [interface interface] [dlci] [64-bit]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

show policy-map [policy-map]

Example:

Router# show policy-map

Displays the configuration of all classes for a specified service policy map or all classes for all existing policy maps.

Step 3 

show policy-map interface interface-name [dlci dlci] [input | output]

Example:

Router# show policy interface Serial3/1.1

Displays the packet statistics of all classes that are configured for all service policies either on the specified interface or subinterface or on a specific permanent virtual circuit (PVC) on the interface.

Step 4 

show frame-relay pvc [interface interface] [dlci] [64-bit]

Example:

Router# show frame-relay pvc 202

Displays statistics about permanent virtual circuits (PVCs) for Frame Relay interface.

Configuration Examples for Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation

•Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Examples

•Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Example

Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Examples

The following examples show the configuration of Frame Relay voice-adaptive traffic shaping and fragmentation. The first example shows end-to-end fragmentation configured in a map class that is associated with PVC 100. In the second example, end-to-end fragmentation is configured directly on the interface.

With both example configurations, priority-queue packets or H.323 call setup signaling packets destined for PVC 100 will result in the reduction of the sending rate from CIR to minCIR and the activation of FRF.12 end-to-end fragmentation. If signaling packets and priority-queue packets are not detected for 50 seconds, the sending rate will increase to CIR and fragmentation will be deactivated.

Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation with End-to-End Fragmentation Configured in a Map Class 

interface serial0

 encapsulation frame-relay

 frame-relay fragmentation voice-adaptive deactivation 50

 frame-relay interface-dlci 100

  class voice_adaptive_class

! 

map-class frame-relay voice_adaptive_class

 frame-relay fragment 80 

 service-policy output shape


class-map match-all voice

 match access-group 102

class-map match-all data

 match access-group 101


policy-map vats

 class voice

  priority 10

 class data

  bandwidth 10  


policy-map shape

 class class-default

  shape average 60000

  shape adaptive 30000

  shape fr-voice-adapt deactivation 50

  service-policy vats

Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation with End-to-End Fragmentation Configured on the Interface 

interface serial0

 encapsulation frame-relay

 frame-relay fragmentation voice-adaptive deactivation 50

 frame-relay interface-dlci 100

  class voice_adaptive_class

  frame-relay fragment 80 end-to-end

!

map-class frame-relay voice_adaptive_class

 service-policy output shape

class-map match-all voice

 match access-group 102

class-map match-all data

 match access-group 101    

policy-map vats

 class voice

  priority 10

 class data

  bandwidth 10 


policy-map shape

 class class-default

  shape average 60000

  shape adaptive 30000

  shape fr-voice-adapt deactivation 50

  service-policy vats

Verifying Frame Relay Voice-Adaptive Traffic Shaping and Fragmentation Example

Sample Output for the show policy-map Command

The following sample output for the show-policy map command indicates that Frame Relay voice-adaptive traffic shaping is configured in the class-default class in the policy map "MQC-SHAPE-LLQ1" and that the deactivation timer is set at 30 seconds. 

Router# show policy-map


  Policy Map VSD1

    Class VOICE1

      Strict Priority

      Bandwidth 10 (kbps) Burst 250 (Bytes)

    Class SIGNALS1

      Bandwidth 8 (kbps) Max Threshold 64 (packets)

    Class DATA1

      Bandwidth 15 (kbps) Max Threshold 64 (packets)


  Policy Map MQC-SHAPE-LLQ1

    Class class-default

      Traffic Shaping

         Average Rate Traffic Shaping

                 CIR 63000 (bps) Max. Buffers Limit 1000 (Packets)

                 Adapt to 8000 (bps)

                 Voice Adapt Deactivation Timer 30 Sec 

      service-policy VSD1

Sample Output for the show policy interface Command

The following sample output shows that Frame Relay voice-adaptive traffic shaping is active and has 29 seconds left on the deactivation timer. This means that the current sending rate on DLCI 201 is minCIR, but if no voice packets are detected for 29 seconds, the sending rate will increase to CIR. 

Router# show policy interface Serial3/1.1


 Serial3/1.1:DLCI 201 -


  Service-policy output:MQC-SHAPE-LLQ1

    Class-map:class-default (match-any)

      1434 packets, 148751 bytes

      30 second offered rate 14000 bps, drop rate 0 bps

      Match:any

      Traffic Shaping

           Target/Average   Byte   Sustain   Excess    Interval  Increment

             Rate           Limit  bits/int  bits/int  (ms)      (bytes)

            63000/63000     1890   7560      7560      120       945

        Adapt  Queue     Packets   Bytes     Packets   Bytes     Shaping

        Active Depth                         Delayed   Delayed   Active

        BECN   0         1434      162991    26        2704      yes

        Voice Adaptive Shaping active, time left 29 secs 


      Service-policy :VSD1


        Class-map:VOICE1 (match-all)

          9 packets, 621 bytes

          30 second offered rate 0 bps, drop rate 0 bps

          Match:access-group 111

          Match:not access-group 112

          Queueing

            Strict Priority

            Output Queue:Conversation 24

            Bandwidth 10 (kbps) Burst 250 (Bytes)

            (pkts matched/bytes matched) 18/1242

            (total drops/bytes drops) 0/0

        Class-map:SIGNALS1 (match-all)

          0 packets, 0 bytes

          30 second offered rate 0 bps, drop rate 0 bps

          Match:access-group 112

          Queueing

            Output Queue:Conversation 25

            Bandwidth 8 (kbps) Max Threshold 64 (packets)

            (pkts matched/bytes matched) 0/0

        (depth/total drops/no-buffer drops) 0/0/0


        Class-map:DATA1 (match-all)

          1424 packets, 148096 bytes

          30 second offered rate 14000 bps, drop rate 0 bps

          Match:access-group 113

          Queueing

            Output Queue:Conversation 26

            Bandwidth 15 (kbps) Max Threshold 64 (packets)

            (pkts matched/bytes matched) 1442/149968

        (depth/total drops/no-buffer drops) 0/0/0

        Class-map:class-default (match-any)

          1 packets, 34 bytes

          30 second offered rate 0 bps, drop rate 0 bps

          Match:any

Sample Output for the show frame-relay pvc Command

The following sample output indicates that Frame Relay voice-adaptive fragmentation is active on DLCI 202 and there are 29 seconds left on the deactivation timer. If no packets are detected in the priority queue and no H.323 signaling packets are detected in the next 29 seconds, fragmentation will stop. 

Router# show frame-relay pvc 202

PVC Statistics for interface Serial3/1 (Frame Relay DTE)

DLCI = 202, DLCI USAGE = LOCAL, PVC STATUS = STATIC, INTERFACE = Serial3/1.2

  input pkts 0             output pkts 479          in bytes 0

  out bytes 51226          dropped pkts 0           in pkts dropped 0

  out pkts dropped 0                out bytes dropped 0

  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0

  out BECN pkts 0          in DE pkts 0             out DE pkts 0

  out bcast pkts 0         out bcast bytes 0

  5 minute input rate 0 bits/sec, 0 packets/sec 

  5 minute output rate 5000 bits/sec, 5 packets/sec

  pvc create time 00:23:36, last time pvc status changed 00:23:31     

  fragment type end-to-end fragment size 80 adaptive active, time left 29 secs

Additional References

The following sections provide additional information related to Frame Relay voice-adaptive traffic shaping and fragmentation:

•Related Documents

•Standards

•MIBs

•RFCs

•Technical Assistance

Related Documents

Related Topic
Document Title

Traffic shaping, low latency queueing for Frame Relay, and Modular QoS CLI configuration tasks

Cisco IOS Quality of Service Configuration Guide, Release 12.2

Traffic shaping, low latency queueing for Frame Relay, and Modular QoS CLI commands

Cisco IOS Quality of Service Command Reference, Release 12.2 T

Frame Relay fragmentation configuration tasks

Cisco IOS Wide-Area Networking Configuration Guide, Release 12.2

Frame Relay fragmentation commands

Cisco IOS Wide-Area Networking Command Reference, Release 12.2 T

Frame Relay interface queueing and fragmentation configuration tasks and commands

"Frame Relay Queueing and Fragmentation at the Interface," Cisco IOS Release 12.2(13)T feature module

Adaptive Frame Relay traffic shaping for interface congestion configuration tasks and commands

"Adaptive Frame Relay Traffic Shaping for Interface Congestion," Cisco IOS Release 12.2(4)T feature module


Standards

Standards
Title

No new or modified standards are supported by this feature. Support for existing standards has not been modified by this feature.

—


MIBs

MIBs
MIBs Link

No new or modified MIBs are supported by this feature. Support for existing MIBs has not been modified by this feature.

To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml


To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://tools.cisco.com/ITDIT/MIBS/servlet/index

If Cisco MIB Locator does not support the MIB information that you need, you can also obtain a list of supported MIBs and download MIBs from the Cisco MIBs page at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

To access Cisco MIB Locator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL:

http://www.cisco.com/register

RFCs

RFCs
Title

No new or modified RFCs are supported by this feature. Support for existing RFCs has not been modified by this feature.

—


Technical Assistance

Description
Link

Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.

http://www.cisco.com/public/support/tac/home.shtml


Command Reference

This section documents new and modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 T command reference publications.

New Commands

•frame-relay fragmentation voice-adaptive

•shape fr-voice-adapt

Modified Commands

•show frame-relay pvc

•show policy-map

•show policy-map interface

frame-relay fragmentation voice-adaptive

To enable voice-adaptive Frame Relay fragmentation, use the frame-relay fragmentation voice-adaptive command in interface configuration mode. To disable voice-adaptive Frame Relay fragmentation, use the no form of this command.

frame-relay fragmentation voice-adaptive [deactivation seconds]

no frame-relay fragmentation voice-adaptive

Syntax Description

deactivation seconds

(Optional) Number of seconds that must elapse after the last voice packet is transmitted before fragmentation is deactivated. The range is from 1 to 10000.


Defaults

Voice-adaptive Frame Relay fragmentation is not enabled.
Seconds: 30

Command Modes

Interface configuration

Command History

Release
Modification

12.2(15)T

This command was introduced.


Usage Guidelines

Frame Relay voice-adaptive fragmentation can be used in conjunction with Frame Relay voice-adaptive traffic shaping to reduce network congestion and improve voice transmission quality.

The frame-relay fragmentation voice-adaptive command can be used only on main interfaces. This command is not supported on subinterfaces.

Frame Relay voice-adaptive fragmentation enables a router to fragment large packets whenever packets (usually voice) are detected in the low latency queueing priority queue or H.323 call setup signaling packets are present. When there are no packets in priority queue for a configured period of time and signaling packets are not present, fragmentation is stopped.

Note Although the priority queue is generally used for voice traffic, Frame Relay voice-adaptive fragmentation will respond to any packets (voice or data) in the priority queue.

Note the following prerequisites for Frame Relay voice-adaptive fragmentation:

•End-to-end fragmentation must be configured in a map class by using the frame-relay fragment command or on the interface by using the frame-relay fragment end-to-end command.

•Frame Relay traffic shaping or traffic shaping using the Modular QoS CLI (MQC) must be configured. If end-to-end fragmentation is configured on the interface, traffic shaping using the MQC must be configured.

•Low latency queueing must be configured.

Frame Relay voice-adaptive fragmentation supports FRF.12 fragmentation only. Neither FRF.11 Annex C nor Cisco proprietary fragmentation is supported.

Examples

The following examples show the configuration of Frame Relay voice-adaptive traffic shaping and fragmentation. The first example shows end-to-end fragmentation configured in a map class that is associated with PVC 100. In the second example, end-to-end fragmentation is configured directly on the interface.

With both example configurations, priority-queue packets or H.323 call setup signaling packets destined for PVC 100 will result in the reduction of the sending rate from CIR to minCIR and the activation of FRF.12 end-to-end fragmentation. If signaling packets and priority-queue packets are not detected for 50 seconds, the sending rate will increase to CIR and fragmentation will be deactivated.

Frame Relay Voice-Adaptive Fragmentation with End-to-End Fragmentation Configured in a Map Class 

interface serial0

 encapsulation frame-relay

 frame-relay fragmentation voice-adaptive deactivation 50

 frame-relay interface-dlci 100

  class voice_adaptive_class

! 

map-class frame-relay voice_adaptive_class

 frame-relay fair-queue

 frame-relay fragment 80 

 service-policy output shape

Frame Relay Voice-Adaptive Fragmentation with End-to-End Fragmentation Configured on the Interface 

interface serial0

 encapsulation frame-relay

 frame-relay fragmentation voice-adaptive deactivation 50

 frame-relay fragment 80 end-to-end

 frame-relay interface-dlci 100

  class voice_adaptive_class

Related Commands

Command
Description

frame-relay fragment

Enables fragmentation of Frame Relay frames for a Frame Relay map class.

frame-relay fragment end-to-end

Enables fragmentation of Frame Relay frames on an interface.

shape fr-voice-adapt

Enables Frame Relay voice-adaptive traffic shaping.

show frame-relay pvc

Displays statistics about PVCs for Frame Relay interfaces.


shape fr-voice-adapt

To enable Frame Relay voice-adaptive traffic shaping, use the shape fr-voice-adapt command in policy-map class configuration mode. To disable Frame Relay voice-adaptive traffic shaping, use the no form of this command.

shape fr-voice-adapt [deactivation seconds]

no shape fr-voice-adapt

Syntax Description

deactivation seconds

(Optional) Number of seconds that must elapse after the last voice packet is transmitted before the sending rate is increased to the committed information rate (CIR). The range is from 1 to 10000.


Defaults

Frame Relay voice-adaptive traffic shaping is not enabled.
Seconds: 30

Command Modes

Policy-map class configuration

Command History

Release
Modification

12.2(15)T

This command was introduced.


Usage Guidelines

Frame Relay voice-adaptive traffic shaping enables a router to reduce the permanent virtual circuit (PVC) sending rate to the minimum CIR (minCIR) whenever packets (usually voice) are detected in the low latency queueing priority queue or H.323 call setup signaling packets are present. When there are no packets in priority queue and signaling packets are not present for a configured period of time, the router increases the PVC sending rate from minCIR to CIR to maximize throughput.

The shape fr-voice-adapt command can be configured only in the class-default class. If you configure the shape fr-voice-adapt command in another class, the associated Frame Relay map class will be rejected when you attach it to the interface.

Frame Relay voice-adaptive traffic shaping can be used with other types of adaptive traffic shaping. For example, when both voice-adaptive traffic shaping and adaptive shaping based on interface congestion are configured, the sending rate will change to minCIR if there are packets in the priority queue or the interface queue size exceeds the configured threshold.

Note Although the priority queue is generally used for voice traffic, Frame Relay voice-adaptive traffic shaping will respond to any packets (voice or data) in the priority queue.

In order to use Frame Relay voice-adaptive traffic shaping, you must have low latency queueing and traffic shaping configured using the Modular QoS CLI.

Examples

The following example shows the configuration of Frame Relay voice-adaptive traffic shaping and fragmentation. With this configuration, priority- queue packets or H.323 call setup signaling packets destined for PVC 100 will result in the reduction of the sending rate from CIR to minCIR and the activation of FRF.12 end-to-end fragmentation. If signaling packets and priority-queue packets are not detected for 50 seconds, the sending rate will increase to CIR and fragmentation will be turned off. 

interface serial0

 encapsulation frame-relay

 frame-relay fragmentation voice-adaptive deactivation 50

 frame-relay fragment 80 end-to-end

 frame-relay interface-dlci 100

  class voice_adaptive_class

!

map-class frame-relay voice_adaptive_class

 frame-relay fair-queue  

 service-policy output shape

class-map match-all voice

 match access-group 102

class-map match-all data

 match access-group 101    

policy-map vats

 class voice

  priority 10

 class data

  bandwidth 10 


policy-map shape

 class class-default

  shape average 60000

  shape adaptive 30000

  shape fr-voice-adapt deactivation 50

  service-policy vats

Related Commands

Command
Description

frame-relay fragmentation voice-adaptive

Enables voice-adaptive Frame Relay fragmentation.

show policy-map

Displays the configuration of all classes for a specified service policy map or all classes for all existing policy maps.

show policy-map interface

Displays the packet statistics of all classes that are configured for all service policies either on the specified interface or subinterface or on a specific PVC on the interface.


show frame-relay pvc

To display statistics about permanent virtual circuits (PVCs) for Frame Relay interfaces, use the show frame-relay pvc command in privileged EXEC mode.

show frame-relay pvc [interface interface] [dlci] [64-bit]

Syntax Description

interface

(Optional) Indicates a specific interface for which PVC information will be displayed.

interface

(Optional) Interface number containing the data-link connection identifiers (DLCIs) for which you wish to display PVC information.

dlci

(Optional) A specific DLCI number used on the interface. Statistics for the specified PVC are displayed when a DLCI is also specified.

64-bit

(Optional) Displays 64-bit counter statistics.


Command Modes

Privileged EXEC

Command History

Release
Modification

10.0

This command was introduced.

12.0(1)T

This command was modified to display statistics about virtual access interfaces used for PPP connections over Frame Relay.

12.0(3)XG

This command was modified to include the fragmentation type and size associated with a particular PVC when fragmentation is enabled on the PVC.

12.0(4)T

This command was modified to include the fragmentation type and size associated with a particular PVC when fragmentation is enabled on the PVC.

12.0(5)T

This command was modified to include information on the special voice queue that is created using the queue keyword of the frame-relay voice bandwidth command.

12.1(2)T

This command was modified to display the following information:

•Details about the policy map attached to a specific PVC.

•The priority configured for PVCs within Frame Relay PVC interface priority queueing.

•Details about Frame Relay traffic shaping and policing on switched PVCs.

12.0(12)S