IP SLAs TWAMP Responder

This module describes how to configure an IETF Two-Way Active Measurement Protocol (TWAMP) responder on a Cisco device to measure IP performance between the Cisco device and a non-Cisco TWAMP control device on your network.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for IP SLAs TWAMP Responder

For the IP SLAs TWAMP responder to function, a TWAMP control-client and the session-sender must be configured in your network.

Restrictions for IP SLAs TWAMP Responder

  • For IP SLAs TWAMP Responder v1.0, the TWAMP server and the session-reflector must be configured on the same Cisco device.

  • Time stamping is not supported for TWAMP test packets that ingress/egress via management interface.

  • Time stamping is not supported on interfaces that are not routed or BDI interfaces.

  • Time stamping is not supported on MPLS/VPLS interfaces.

  • TWAMP client and session sender is not supported.

  • Upto nine session-senders can be configured for one TWAMP responder.

  • TWAMP Light mode is not supported.

Information About IP SLAs TWAMP Responder

TWAMP

The IETF Two-Way Active Measurement Protocol (TWAMP) defines a standard for measuring round-trip network performance between any two devices that support the TWAMP protocols. The TWAMP-Control protocol is used to set up performance measurement sessions. The TWAMP-Test protocol is used to send and receive performance-measurement probes.

The TWAMP architecture is composed of the following four logical entities that are responsible for starting a monitoring session and exchanging packets:

  • The control-client sets up, starts, and stops TWAMP-Test sessions.

  • The session-sender instantiates TWAMP-Test packets that are sent to the session-reflector.

  • The session-reflector reflects a measurement packet upon receiving a TWAMP-Test packet. The session reflector does not collect packet statistics in TWAMP.

  • The TWAMP server is an end system that manages one or more TWAMP sessions and is also capable of configuring per-session ports in the end points. The server listens on the TCP port. The session-refector and server make up the TWAMP responder in an IP SLAs operation.

Although TWAMP defines the different entities for flexibility, it also allows for logical merging of the roles on a single device for ease of implementation. The figure below shows the four entities that make up the TWAMP architecture.

Figure 1. TWAMP Architecture

IP SLAs TWAMP Responder v1.0

A TWAMP responder interoperates with the control-client and session-sender on another device that supports TWAMP. In the IP SLAs TWAMP Responder v1.0 feature, the session-reflector and TWAMP server that make up the responder must be co-located on the same device.

In the figure below, one device is the control-client and session-sender (TWAMP control device), and the other two devices are Cisco devices that are configured as IP SLAs TWAMP responders. Each IP SLAs TWAMP responder is both a TWAMP server and a session-reflector.

Figure 2. IP SLAs TWAMP Responders in a Basic TWAMP Deployment

How to Configure an IP SLAs TWAMP Responder


Note
Time stamping for sender (T1, T4) and receiver (T3, T2) is performed by hardware, instead of software to improve the accuracy of jitter and latency measurements effective Cisco IOS-XE Everest 16.6.1.

Configuring the TWAMP Server


Note

For IP SLAs TWAMP Responder v1.0, the TWAMP server and the session-reflector are configured on the same device.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ip sla server twamp

    4.    port port-number

    5.    timer inactivity seconds

    6.    end


DETAILED STEPS
    Step 1   enable


    Example:
    Device> enable

    Enables privileged EXEC mode.

    • Enter your password if prompted.

    Step 2   configure terminal


    Example:
    Device# configure terminal

    Enters global configuration mode.

    Step 3   ip sla server twamp


    Example:
    Device(config)#  ip sla server twamp

    Configures the device as a TWAMP server and enters TWAMP server configuration mode.

    Step 4   port port-number


    Example:
    Device(config-twamp-srvr)# port 9000

    (Optional) Configures the port to be used by the TWAMP server to listen for connection and control requests.

    Step 5   timer inactivity seconds


    Example:
    Device(config-twamp-srvr)# timer inactivity 300

    (Optional) Configures the inactivity timer for a TWAMP control session.

    Step 6   end


    Example:
    Device(config-twamp-srvr)# end

    Returns to privileged EXEC mode.

    Configuring the Session-Reflector


    Note

    For IP SLAs TWAMP Responder v1.0, the TWAMP server and the session-reflector are configured on the same device.

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    ip sla responder twamp

      4.    timeout seconds

      5.    end


    DETAILED STEPS
      Step 1   enable


      Example:
      Device> enable

      Enables privileged EXEC mode.

      • Enter your password if prompted.

      Step 2   configure terminal


      Example:
      Device# configure terminal

      Enters global configuration mode.

      Step 3   ip sla responder twamp


      Example:
      Device(config)# ip sla responder twamp

      Configures the device as a TWAMP responder and enters TWAMP reflector configuration mode.

      Step 4   timeout seconds


      Example:
      Device(config-twamp-ref)#  timeout 300

      (Optional) Configures an inactivity timer for a TWAMP test session.

      Step 5   end


      Example:
      Device(config-twamp-ref)# end

      Exits to privileged EXEC mode.

      Configuration Examples for IP SLAs TWAMP Responder

      IP SLAs TWAMP Responder v1.0 Example

      The following example and partial output shows how to configure the TWAMP server and the session-reflector for IP SLAs TWAMP Responder v1.0 on the same Cisco device. In this configuration, port 862 is the (default) port to be used by the TWAMP server to listen for connection and control requests. The default port for the server listener is the RFC-specified port and can be reconfigured, if required.

      Note

      In order for the IP SLAs TWAMP responder to function, a control-client and the session-sender must be configured in your network. 

      Device> enable
Device# configure terminal
Device(config)#  ip sla server twamp
Device(config-twamp-srvr)#  exit
Device(config)#  ip sla responder twamp
Device(config-twamp-ref)# end
Device> show running-config  
.
.
.
ip sla responder
ip sla responder twamp
ip sla server twamp
port 862

      Additional References

      Related Documents

      Related Topic

      Document Title

      Cisco IOS commands

      Cisco IOS Master Commands List, All Releases

      IP SLAs commands

      Cisco IOS IP SLAs Command Reference

      Standards and RFCs

      Standard/RFC

      Title

      RFC 5357

      Two-Way Active Measurement Protocol (TWAMP)

      RFC 4656

      One-way Active Measurement Protocol (OWAMP)

      Technical Assistance

      Description

      Link

      The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

      http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

      Feature Information for IP SLAs TWAMP Responder

      The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

      Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.
      Table 1 Feature Information for IP SLAs TWAMP Responder

      Feature Name

      Releases

      Feature Information

      IP SLAs TWAMP Responder v1.0

      Cisco IOS XE Release 3.6S

      Cisco IOS XE Release 3.12S

      This feature enables you to configure the TWAMP server and the session-reflector on a Cisco device for measuring the round-trip performance between an IP SLAs TWAMP responder and a non-Cisco TWAMP control device in your network.

      The following commands were introduced or modified: ip sla responder twamp, ip sla server twamp, port (twamp), show ip sla standards, show ip sla twamp connection, show ip sla twamp session, show ip sla twamp standards, timer inactivity, timeout (twamp)..

      In Cisco IOS XE Release 3.12S, support was added for RFC 5357.

      TWAMP RFC compliance

      Cisco IOS XE Release 3.12S

      In Cisco IOS XE Release 3.12S, support was added for RFC 5357.