Contents

Configuring Header Compression Using IPHC Profiles

Header compression is a mechanism that compresses the IP header in a packet before the packet is transmitted. Header compression reduces network overhead and speeds up the transmission of either Real-Time Transport Protocol (RTP) or Transmission Control Protocol (TCP) packets.

One method of configuring header compression on your network is to use an IP header compression (IPHC) profile. An IPHC profile is a kind of template within which you can configure the type of header compression that you want to use, set all of the optional features and parameters for header compression, and then apply the profile to an interface, subinterface, or Frame Relay permanent virtual circuit (PVC).

This module describes the concepts and tasks for configuring header compression using IPHC profiles.

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 at the end of this module.

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 Using IPHC Profiles

Before using IPHC profiles to configure header compression, read the information in the "Header Compression" module.

Restrictions for Using IPHC Profiles

IPHC profiles are not supported on L2TP networks.

Information About Using IPHC Profiles

Benefits of Using IPHC Profiles

An IPHC profile provides a flexible means of enabling header compression and the options associated with header compression. For example, header compression (and the header compression options) can be enabled once in an IPHC profile, and then the IPHC profile can be applied to one or more of the following:

  • An interface
  • A subinterface
  • A Frame Relay PVC

IPHC Profile Types

You use the iphc-profile command to create the IPHC profile. When you create an IPHC profile, you must specify the IPHC profile type. The IPHC profile choices are Internet Engineering Task Force (IETF) or van-jacobson. You specify the IPHC profile type with the ietf keyword or the van-jacobson keyword of the iphc-profile command.

The ietf profile type conforms with and supports the standards established with RFC 2507, RFC 2508, RFC 3544, and RFC 3545 and is typically associated with non-TCP header compression (for example, RTP header compression). The van-jacobson profile type conforms with and supports the standards established with RFC 1144 and is typically associated with TCP header compression.

Considerations When Specifying the IPHC Profile Type

When specifying the IPHC profile type, consider whether you are compressing TCP traffic or non-TCP (that is, RTP) traffic. Also consider the header compression format capabilities of the remote network link to which you will be sending traffic.

The IPHC profile type that you specify directly affects the header compression format used on the remote network links to which the IPHC profile is applied. Only TCP traffic is compressed on remote network links using a van-jacobson IPHC profile, whereas both TCP and non-TCP (for example, RTP) traffic is compressed on remote network links using an ietf IPHC profile.


Note


The header compression format in use on the router that you are configuring and the header compression format in use on the remote network link must match.


Configurable Header Compression Features and Settings

The specific header compression features and settings that you can configure (that is, enable or modify) are determined by the IPHC profile type that you select (either van-jacobson or ietf) when you create the IPHC profile. There is one set of features and options for the van-jacobson IPHC profile type and another set for the ietf IPHC profile type. Both sets are listed below.

Features and Settings for van-jacobson IPHC Profile Type Header Compression

If you specify van-jacobson as the IPHC profile type, you can enable TCP header compression and set the number of TCP contexts. The table below lists the van-jacobson IPHC profile type header compression features and settings that are available and the command used to enable that feature or setting.

Table 1 van-jacobson IPHC Profile Type Header Compression Features and Settings

Feature or Setting

Command

TCP header compression

tcp

Number of contexts available for TCP header compression

tcp contexts

Features and Settings for ietf IPHC Profile Type Header Compression

If you specify ietf as the IPHC profile type, you can enable non-TCP header compression (that is, RTP header compression), along with a number of additional features and settings. The table below lists the ietf IPHC profile type header compression features and settings that are available and the command used to enable that feature or setting.

Table 2 ietf IPHC Profile Type Header Compression Features and Settings

Feature or Setting

Command

Non-TCP header compression

non-tcp

Number of contexts available for non-TCP header compression

non-tcp contexts

RTP header compression

rtp

Enhanced Compressed Real-Time Transport Protocol (ECRTP) on an interface

recoverable-loss

Context refresh (full-header refresh) options, such as the amount of time to wait before a full-header is refreshed

refresh max-time refresh max-period refresh rtp

Context-status feedback messages from the interface or link

feedback

Maximum size of the compressed IP header

maximum header

TCP header compression

tcp

Number of contexts available for TCP header compression

tcp contexts

Tasks for Using IPHC Profiles

The tasks for configuring header compression using an IPHC profile are described below.

  1. Create the IPHC profile and specify the IPHC profile type (ietf or van-jacobson) that you want to use.
  2. Enable or set the header compression features available for the IPHC profile type that you specified when you created the IPHC profile. The header compression features vary by IPHC profile type.
  3. Attach the IPHC profile to an interface, subinterface, or Frame Relay PVC.
  4. Display information about the IPHC profiles that you have created.

The figure below illustrates the high-level processes for configuring header compression using IPHC profiles.

Figure 1. Flowchart for Configuring Header Compression Using IPHC Profiles

How to Configure Header Compression Using IPHC Profiles

Creating an IPHC Profile

The first task is to create an IPHC profile. When you create an IPHC profile, you can create either an ietf IPHC profile or a van-jacobson IPHC profile, by using the corresponding keyword of the iphc-profile command.

To create either an ietf IPHC profile or a van-jacobson IPHC profile, complete the following steps.

Before You Begin

Before completing the steps listed below, determine the type of IPHC profile that you want to create: ietf or van-jacobson. The IPHC profile type that you create directly affects the header compression options available for you.

For more information about IPHC profile types and considerations for selecting one or the other, see the IPHC Profile Types.


Note


The IPHC profile name must be unique and cannot be longer than 32 characters. IPHC profile names exceeding this maximum are truncated to 32 characters.

>
SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    iphc-profile profile-name {ietf | van-jacobson}

    4.    end


DETAILED STEPS
     Command or ActionPurpose
    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 iphc-profile profile-name {ietf | van-jacobson}


    Example:
    Router(config)# iphc-profile profile2 ietf
     

    Creates an IPHC profile and enters IPHC-profile configuration mode.

    • Enter the IPHC profile name and the IPHC profile type keyword.
     
    Step 4 end


    Example:
    Router(config-iphcp)# end
     

    (Optional) Exits IPHC-profile configuration mode.

     

    What to Do Next

    So far you have created either an ietf IPHC profile or a van-jacobson IPHC profile.

    The next step is to enable or set any additional header compression features or options available for the type of IPHC profile that you created.

    Choose one of the following:

    Enabling the Options for van-jacobson IPHC Profile Type Header Compression

    If you created a van-jacobson IPHC profile, you can enable TCP header compression and set the number of TCP contexts.


    Note


    If you created an ietf IPHC profile, the header compression options available to you are documented in the Enabling the Options for ietf IPHC Profile Type Header Compression.


    To enable TCP header compression set the number of TCP contexts, complete the following steps.

    Before You Begin

    The IPHC profile must exist.

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    iphc-profile profile-name

      4.    tcp

      5.    tcp contexts {absolute number-of-contexts | kbps-per-context kbps}

      6.    end


    DETAILED STEPS
       Command or ActionPurpose
      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 iphc-profile profile-name


      Example:
      Router(config)# iphc-profile profile2
       

      Specifies the IPHC profile and enters IPHC-profile configuration mode.

      • Enter the IPHC profile name.
       
      Step 4 tcp


      Example:
      Router(config-iphcp)# tcp
       

      (Optional) Enables TCP header compression.

       
      Step 5 tcp contexts {absolute number-of-contexts | kbps-per-context kbps}


      Example:
      Router(config-iphcp)# tcp contexts absolute 25
       

      (Optional) Sets the number of TCP contexts.

      • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
       
      Step 6 end


      Example:
      Router(config-iphcp)# end
       

      (Optional) Exits IPHC-profile configuration mode.

       

      What to Do Next

      The next step is to attach the IPHC profile to an interface, a subinterface, or a Frame Relay PVC. For the instructions to follow, see the Attaching the IPHC Profile.

      Enabling the Options for ietf IPHC Profile Type Header Compression


      Note


      If you created a van-jacobson IPHC profile, complete the tasks in the Enabling the Options for van-jacobson IPHC Profile Type Header Compression.


      If you created an ietf IPHC profile, you can enable or set a variety of header compression options. These options include enabling non-TCP header compression, enabling RTP header compression, and enabling ECRTP. For a list of the additional header compression features or settings available with an ietf IPHC profile, see the Enabling the Options for ietf IPHC Profile Type Header Compression.
      Before You Begin

      The IPHC profile must exist.

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    iphc-profile profile-name

        4.    non-tcp

        5.    non-tcp contexts {absolute number-of-contexts | kbps-per-context kbps }

        6.    rtp

        7.    recoverable-loss {dynamic | packet-drops}

        8.    refresh max-period {number-of-packets | infinite}

        9.    refresh max-time {length-of-time | infinite}

        10.    refresh rtp

        11.    feedback

        12.    maximum header max-header-size

        13.    tcp

        14.    Router(config-iphcp)# tcp contexts absolute 75

        15.    end


      DETAILED STEPS
         Command or ActionPurpose
        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 iphc-profile profile-name


        Example:
        Router(config)# iphc-profile profile3
         

        Specifies the IPHC profile and enters IPHC-profile configuration mode.

        • Enter the IPHC profile name.
         
        Step 4 non-tcp


        Example:
        Router(config-iphcp)# non-tcp
         

        (Optional) Enables non-TCP header compression.

         
        Step 5 non-tcp contexts {absolute number-of-contexts | kbps-per-context kbps }


        Example:
        Router(config-iphcp)# non-tcp contexts absolute 75
         

        (Optional) Sets the number of contexts available for non-TCP header compression.

        • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
         
        Step 6 rtp


        Example:
        Router(config-iphcp)# rtp
         

        (Optional) Enables RTP header compression.

        Note   

        This command automatically enables non-TCP header compression.

         
        Step 7 recoverable-loss {dynamic | packet-drops}


        Example:
        Router(config-iphcp)# recoverable-loss 5
         

        (Optional) Enables ECRTP.

         
        Step 8 refresh max-period {number-of-packets | infinite}


        Example:
        Router(config-iphcp)# refresh max-period 700
         

        (Optional) Sets the number of packets sent between full-header refresh occurrences.

        • Enter the number of packets sent between full-header refresh occurrences, or enter the infinite keyword to indicate no limitation on the number of packets sent between full-header refresh occurrences.
        Note   

        Non-TCP header compression must be enabled first.

         
        Step 9 refresh max-time {length-of-time | infinite}


        Example:
        Router(config-iphcp)# refresh max-time infinite
         

        (Optional) Sets the amount of time to wait before a full-header refresh occurrence.

        • Enter the length of time, in seconds, to wait before a full-header refresh occurrence, or enter the infinite keyword to indicate no limitation on the time between full-header refreshes.
        Note   

        Non-TCP header compression must be enabled first.

         
        Step 10 refresh rtp


        Example:
        Router(config-iphcp)# refresh rtp
         

        (Optional) Enables a context refresh for RTP header compression.

        Note   

        RTP header compression must be enabled first.

         
        Step 11 feedback


        Example:
        Router(config-iphcp)# feedback
         

        (Optional) Disables the context-status feedback messages from the interface or link.

        Note   

        TCP or non-TCP header compression must be enabled first.

         
        Step 12 maximum header max-header-size


        Example:
        Router(config-iphcp)# maximum header 75
         

        (Optional) Specifies the maximum size of the compressed IP header.

        • Enter the maximum size of the compressed IP header, in bytes.
        Note   

        TCP or non-TCP header compression must be enabled first.

         
        Step 13 tcp


        Example:
        Router(config-iphcp)# tcp
         

        (Optional) Enables TCP header compression.

         
        Step 14 Router(config-iphcp)# tcp contexts absolute 75  

        (Optional) Sets the number of contexts available for TCP header compression.

        • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
         
        Step 15 end


        Example:
        Router(config-iphcp)# end
         

        (Optional) Exits IPHC-profile configuration mode.

         

        Attaching the IPHC Profile

        You can attach the IPHC profile (either an ietf IPHC profile or a van-jacobson IPHC profile) to an interface, a subinterface, or a Frame Relay PVC.

        Choose one of the following:

        Attaching an IPHC Profile to an Interface

        To attach an IPHC profile to an interface or subinterface, complete the following steps.

        Before You Begin
        • The IPHC profile must exist.
        • IP must be enabled on the interface or subinterface.
        • The type of encapsulation in use on the interface or subinterface must support header compression. Two types of encapsulation that typically support header compression are PPP and HDLC encapsulation.
        • Header compression must not already be enabled.
        • The interface or subinterface must have sufficient memory.
        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    interface type number [name-tag]

          4.    iphc-profile profile-name

          5.    end


        DETAILED STEPS
           Command or ActionPurpose
          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 [name-tag]


          Example:
          Router(config)# interface fastethernet0
           

          Configures an interface type and enters interface configuration mode.

          • Enter the interface type and the interface number.
           
          Step 4 iphc-profile profile-name


          Example:
          Router(config-if)# iphc-profile profile1
           

          Attaches the IPHC profile to the interface.

          • Enter the IPHC profile to be attached to the interface specified in Step 3 .
           
          Step 5 end


          Example:
          Router(config-if)# end
           

          (Optional) Exits IPHC-profile configuration mode.

           

          Attaching an IPHC Profile to a Frame Relay PVC

          To attach an IPHC profile to a Frame Relay PVC, complete the following steps.

          Before You Begin
          • The IPHC profile must exist.
          • On a network that is using Frame Relay encapsulation, IPHC profiles are supported only in the Frame Relay map-class infrastructure.
          SUMMARY STEPS

            1.    enable

            2.    configure terminal

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

            4.    frame-relay iphc-profile profile-name

            5.    exit

            6.    interface type number [name-tag]

            7.    encapsulation frame-relay

            8.    ip address ip-address mask

            9.    frame-relay interface-dlci dlci

            10.    class name

            11.    end


          DETAILED STEPS
             Command or ActionPurpose
            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 mapclass1
             

            Creates a map class and enters static map class configuration mode.

            • Enter the Frame Relay map class name.
             
            Step 4 frame-relay iphc-profile profile-name


            Example:
            Router(config-map-class)# frame-relay iphc-profile profile2
             

            Attaches the IPHC profile to the Frame Relay map class.

            • Enter the IPHC profile to be attached to the Frame Relay map class created in Step 3 .
             
            Step 5 exit


            Example:
            Router(config-map-class)# exit
             

            Exits static map class configuration mode.

             
            Step 6 interface type number [name-tag]


            Example:
            Router(config)# interface serial2/0
             

            Configures an interface type and enters interface configuration mode.

            • Enter the interface type and the interface number.
             
            Step 7 encapsulation frame-relay


            Example:
            Router(config-if)# encapsulation frame-relay
             

            Enables Frame Relay encapsulation on the interface.

             
            Step 8 ip address ip-address mask


            Example:
            Router(config-if)# ip address 209.165.200.225 255.255.255.224
             

            Sets a primary IP address for an interface.

            • Enter the IP address and mask for the associated IP subnet.
             
            Step 9 frame-relay interface-dlci dlci


            Example:
            Router(config-if)# frame-relay interface-dlci 100
             

            Assigns a data-link connection identifier (DLCI) to a specified Frame Relay interface on the router or access server and enters Frame Relay DLCI configuration mode.

            • Enter the DLCI number to be used on the specified interface.
             
            Step 10 class name


            Example:
            Router(config-fr-dlci)# class mapclass1
             

            Associates a map class with a specified DLCI.

            • Enter the name of the map class to associate with the specified DLCI.
             
            Step 11 end


            Example:
            Router(config-fr-dlci)# end
             

            (Optional) Exits Frame Relay DLCI configuration mode.

             

            Displaying the IPHC Profile Statistics

            In this task, you can display statistical information about the IPHC profiles that you have created and configured. Displaying the IPHC profile statistics allows you to confirm that the IPHC profile is configured as you intended.

            Information reported includes the IPHC profile name and profile type, the type of header compression enabled, whether any optional header compression features (such as the number of contexts) are enabled, and the name of the interface to which the IPHC profile is attached (if applicable).

            To display the IPHC profile statistics, complete the following steps.

            Before You Begin

            The IPHC profile must exist.

            SUMMARY STEPS

              1.    enable

              2.    show iphc-profile [profile-name]

              3.    end


            DETAILED STEPS
               Command or ActionPurpose
              Step 1 enable


              Example:
              Router> enable
               

              Enables privileged EXEC mode.

              • Enter your password if prompted.
               
              Step 2 show iphc-profile [profile-name]


              Example:
              Router# show iphc-profile profile1
               

              Displays configuration information for one or more IPHC profiles.

              • (Optional) Enter the name of the IPHC profile you want to display. If you do not specify an IPHC profile name, all IPHC profiles are displayed.
               
              Step 3 end


              Example:
              Router# end
               

              (Optional) Exits privileged EXEC mode.

               

              Configuration Examples for Using IPHC Profiles

              Example Creating an IPHC Profile

              In the following example, a van-jacobson IPHC profile called profile1 has been created.

              Router> enable
              Router# configure terminal
              Router(config)# iphc-profile profile1 van-jacobson
              Router(config-iphcp)# end
              
              
                    

              In the following example, an ietf IPHC profile called profile2 has been created.

              Router> enable
              Router# configure terminal
              Router(config)# iphc-profile profile2 ietf
              Router(config-iphcp)# end

              Example Enabling TCP Header Compression

              In the following example, TCP header compression has been enabled in a van-jacobson IPHC profile called profile1. Additionally, the number of TCP contexts has been set to 25.

              Router> enable
              Router# configure terminal
              Router(config)# iphc-profile profile1
              Router(config-iphcp)# tcp
              Router(config-iphcp)# tcp contexts absolute 25
              Router(config-iphcp)# end

              Example Enabling Non-TCP Header Compression

              In the following example, RTP header compression has been enabled in an ietf IPHC profile called profile2. Additionally, ECRTP has been enabled with the recoverable-loss command, and the size of the compressed IP header has been set to 75 bytes.

              Router> enable
              Router# configure terminal
              Router(config)# iphc-profile profile2
              Router(config-iphcp)# rtp
              Router(config-iphcp)# recoverable-loss 5
              Router(config-iphcp)# maximum header 75
              Router(config-iphcp)# end
              
              
                  

              Example Attaching the IPHC Profile

              In the following example, an IPHC profile called profile1 is attached to serial interface 0.

              Router> enable
              Router# configure terminal
              Router(config)# interface serial0
              Router(config-if)# iphc-profile profile1
              Router(config-if)# end
              
              
                    

              In the following example, an IPHC profile called profile2 is attached to a Frame Relay map class called mapclass1.

              Router> enable
              Router# configure terminal
              Router(config)# map-class frame-relay mapclass1
              Router(config-map-class)# frame-relay iphc-profile profile2
              Router(config-map-class)# exit
              Router(config)# interface serial2/0
              Router(config-if)# encapsulation frame-relay
              Router(config-if)# ip address 209.165.200.225 255.255.255.224
              Router(config-if)# frame-relay interface-dlci 100
              Router(config-fr-dlci)# class mapclass1
              Router(config-fr-dlci)# end

              Example Reporting IPHC Profile Statistics

              The following is sample output from the show iphc-profile command. In this output, information about two IPHC profiles, profile21 and 20, is displayed.

              Router# show iphc-profile
              IPHC Profile "profile21"
              Type: VJ
                Compressing: TCP 
                Contexts   : TCP fixed at 150 
                Controlled interfaces: (1)
                  Se3/1
              IPHC Profile "profile20"
              Type: IETF
                Compressing: TCP NON-TCP (RTP)
                Contexts   : TCP 1 for each 0 kbits NON-TCP 1 for each 0 kbits 
                Refresh    : NON-TCP and RTP every 5 seconds or 256 packets
                Controlled interfaces: (1)
                  Se3/0
              
              
                  

              Additional References

              The following sections provide references related to IPHC profiles.

              Related Documents

              Related Topic

              Document Title

              Cisco IOS commands

              Cisco IOS Master Commands List, All Releases

              QoS commands: complete command syntax, command modes, command history, defaults, usage guidelines, and examples

              Cisco IOS Quality of Service Solutions Command Reference

              QoS functionality overview

              "Quality of Service Overview" module

              Header compression overview

              "Header Compression" module

              RTP header compression

              "Configuring RTP Header Compression" module

              TCP header compression

              "Configuring TCP Header Compression" module

              Class-based RTP and TCP header compression

              "Configuring Class-Based RTP and TCP Header Compression" module

              Standards

              Standard

              Title

              No new or modified standards are supported, and support for existing standards has not been modified.

              --

              MIBs

              MIB

              MIBs Link

              No new or modified MIBs are supported, and support for existing MIBs has not been modified.

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

              http:/​/​www.cisco.com/​go/​mibs

              RFCs

              RFC

              Title

              RFC 1144

              Compressing TCP/IP Headers for Low-Speed Serial Links

              RFC 2507

              IP Header Compression

              RFC 2508

              Compressing IP/UDP/RTP Headers for Low-Speed Serial Links

              RFC 3544

              IP Header Compression over PPP

              RFC 3545

              Enhanced Compressed RTP (CRTP) for Links with High Delay, Packet Loss and Reordering

              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 Configuring Header Compression Using IPHC Profiles

              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 3 Feature Information for Configuring Header Compression Using IPHC Profiles

              Feature Name

              Releases

              Feature Information

              IPHC Profiles

              12.4(9)T

              The IPHC Profiles feature allows you to configure header compression in a kind of template ("profile") and to apply the profile to interfaces, subinterfaces, or Frame Relay PVCs.

              The following commands were introduced by this feature: feedback, iphc-profile, maximum header, non-tcp, non-tcp contexts, recoverable-loss, refresh max-period, refresh max-time, refresh rtp, rtp, show iphc-profile, tcp, tcp contexts.


              Configuring Header Compression Using IPHC Profiles

              Contents

              Configuring Header Compression Using IPHC Profiles

              Header compression is a mechanism that compresses the IP header in a packet before the packet is transmitted. Header compression reduces network overhead and speeds up the transmission of either Real-Time Transport Protocol (RTP) or Transmission Control Protocol (TCP) packets.

              One method of configuring header compression on your network is to use an IP header compression (IPHC) profile. An IPHC profile is a kind of template within which you can configure the type of header compression that you want to use, set all of the optional features and parameters for header compression, and then apply the profile to an interface, subinterface, or Frame Relay permanent virtual circuit (PVC).

              This module describes the concepts and tasks for configuring header compression using IPHC profiles.

              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 at the end of this module.

              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 Using IPHC Profiles

              Before using IPHC profiles to configure header compression, read the information in the "Header Compression" module.

              Restrictions for Using IPHC Profiles

              IPHC profiles are not supported on L2TP networks.

              Information About Using IPHC Profiles

              Benefits of Using IPHC Profiles

              An IPHC profile provides a flexible means of enabling header compression and the options associated with header compression. For example, header compression (and the header compression options) can be enabled once in an IPHC profile, and then the IPHC profile can be applied to one or more of the following:

              • An interface
              • A subinterface
              • A Frame Relay PVC

              IPHC Profile Types

              You use the iphc-profile command to create the IPHC profile. When you create an IPHC profile, you must specify the IPHC profile type. The IPHC profile choices are Internet Engineering Task Force (IETF) or van-jacobson. You specify the IPHC profile type with the ietf keyword or the van-jacobson keyword of the iphc-profile command.

              The ietf profile type conforms with and supports the standards established with RFC 2507, RFC 2508, RFC 3544, and RFC 3545 and is typically associated with non-TCP header compression (for example, RTP header compression). The van-jacobson profile type conforms with and supports the standards established with RFC 1144 and is typically associated with TCP header compression.

              Considerations When Specifying the IPHC Profile Type

              When specifying the IPHC profile type, consider whether you are compressing TCP traffic or non-TCP (that is, RTP) traffic. Also consider the header compression format capabilities of the remote network link to which you will be sending traffic.

              The IPHC profile type that you specify directly affects the header compression format used on the remote network links to which the IPHC profile is applied. Only TCP traffic is compressed on remote network links using a van-jacobson IPHC profile, whereas both TCP and non-TCP (for example, RTP) traffic is compressed on remote network links using an ietf IPHC profile.


              Note


              The header compression format in use on the router that you are configuring and the header compression format in use on the remote network link must match.


              Configurable Header Compression Features and Settings

              The specific header compression features and settings that you can configure (that is, enable or modify) are determined by the IPHC profile type that you select (either van-jacobson or ietf) when you create the IPHC profile. There is one set of features and options for the van-jacobson IPHC profile type and another set for the ietf IPHC profile type. Both sets are listed below.

              Features and Settings for van-jacobson IPHC Profile Type Header Compression

              If you specify van-jacobson as the IPHC profile type, you can enable TCP header compression and set the number of TCP contexts. The table below lists the van-jacobson IPHC profile type header compression features and settings that are available and the command used to enable that feature or setting.

              Table 1 van-jacobson IPHC Profile Type Header Compression Features and Settings

              Feature or Setting

              Command

              TCP header compression

              tcp

              Number of contexts available for TCP header compression

              tcp contexts

              Features and Settings for ietf IPHC Profile Type Header Compression

              If you specify ietf as the IPHC profile type, you can enable non-TCP header compression (that is, RTP header compression), along with a number of additional features and settings. The table below lists the ietf IPHC profile type header compression features and settings that are available and the command used to enable that feature or setting.

              Table 2 ietf IPHC Profile Type Header Compression Features and Settings

              Feature or Setting

              Command

              Non-TCP header compression

              non-tcp

              Number of contexts available for non-TCP header compression

              non-tcp contexts

              RTP header compression

              rtp

              Enhanced Compressed Real-Time Transport Protocol (ECRTP) on an interface

              recoverable-loss

              Context refresh (full-header refresh) options, such as the amount of time to wait before a full-header is refreshed

              refresh max-time refresh max-period refresh rtp

              Context-status feedback messages from the interface or link

              feedback

              Maximum size of the compressed IP header

              maximum header

              TCP header compression

              tcp

              Number of contexts available for TCP header compression

              tcp contexts

              Tasks for Using IPHC Profiles

              The tasks for configuring header compression using an IPHC profile are described below.

              1. Create the IPHC profile and specify the IPHC profile type (ietf or van-jacobson) that you want to use.
              2. Enable or set the header compression features available for the IPHC profile type that you specified when you created the IPHC profile. The header compression features vary by IPHC profile type.
              3. Attach the IPHC profile to an interface, subinterface, or Frame Relay PVC.
              4. Display information about the IPHC profiles that you have created.

              The figure below illustrates the high-level processes for configuring header compression using IPHC profiles.

              Figure 1. Flowchart for Configuring Header Compression Using IPHC Profiles

              How to Configure Header Compression Using IPHC Profiles

              Creating an IPHC Profile

              The first task is to create an IPHC profile. When you create an IPHC profile, you can create either an ietf IPHC profile or a van-jacobson IPHC profile, by using the corresponding keyword of the iphc-profile command.

              To create either an ietf IPHC profile or a van-jacobson IPHC profile, complete the following steps.

              Before You Begin

              Before completing the steps listed below, determine the type of IPHC profile that you want to create: ietf or van-jacobson. The IPHC profile type that you create directly affects the header compression options available for you.

              For more information about IPHC profile types and considerations for selecting one or the other, see the IPHC Profile Types.


              Note


              The IPHC profile name must be unique and cannot be longer than 32 characters. IPHC profile names exceeding this maximum are truncated to 32 characters.

              >
              SUMMARY STEPS

                1.    enable

                2.    configure terminal

                3.    iphc-profile profile-name {ietf | van-jacobson}

                4.    end


              DETAILED STEPS
                 Command or ActionPurpose
                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 iphc-profile profile-name {ietf | van-jacobson}


                Example:
                Router(config)# iphc-profile profile2 ietf
                 

                Creates an IPHC profile and enters IPHC-profile configuration mode.

                • Enter the IPHC profile name and the IPHC profile type keyword.
                 
                Step 4 end


                Example:
                Router(config-iphcp)# end
                 

                (Optional) Exits IPHC-profile configuration mode.

                 

                What to Do Next

                So far you have created either an ietf IPHC profile or a van-jacobson IPHC profile.

                The next step is to enable or set any additional header compression features or options available for the type of IPHC profile that you created.

                Choose one of the following:

                Enabling the Options for van-jacobson IPHC Profile Type Header Compression

                If you created a van-jacobson IPHC profile, you can enable TCP header compression and set the number of TCP contexts.


                Note


                If you created an ietf IPHC profile, the header compression options available to you are documented in the Enabling the Options for ietf IPHC Profile Type Header Compression.


                To enable TCP header compression set the number of TCP contexts, complete the following steps.

                Before You Begin

                The IPHC profile must exist.

                SUMMARY STEPS

                  1.    enable

                  2.    configure terminal

                  3.    iphc-profile profile-name

                  4.    tcp

                  5.    tcp contexts {absolute number-of-contexts | kbps-per-context kbps}

                  6.    end


                DETAILED STEPS
                   Command or ActionPurpose
                  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 iphc-profile profile-name


                  Example:
                  Router(config)# iphc-profile profile2
                   

                  Specifies the IPHC profile and enters IPHC-profile configuration mode.

                  • Enter the IPHC profile name.
                   
                  Step 4 tcp


                  Example:
                  Router(config-iphcp)# tcp
                   

                  (Optional) Enables TCP header compression.

                   
                  Step 5 tcp contexts {absolute number-of-contexts | kbps-per-context kbps}


                  Example:
                  Router(config-iphcp)# tcp contexts absolute 25
                   

                  (Optional) Sets the number of TCP contexts.

                  • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
                   
                  Step 6 end


                  Example:
                  Router(config-iphcp)# end
                   

                  (Optional) Exits IPHC-profile configuration mode.

                   

                  What to Do Next

                  The next step is to attach the IPHC profile to an interface, a subinterface, or a Frame Relay PVC. For the instructions to follow, see the Attaching the IPHC Profile.

                  Enabling the Options for ietf IPHC Profile Type Header Compression


                  Note


                  If you created a van-jacobson IPHC profile, complete the tasks in the Enabling the Options for van-jacobson IPHC Profile Type Header Compression.


                  If you created an ietf IPHC profile, you can enable or set a variety of header compression options. These options include enabling non-TCP header compression, enabling RTP header compression, and enabling ECRTP. For a list of the additional header compression features or settings available with an ietf IPHC profile, see the Enabling the Options for ietf IPHC Profile Type Header Compression.
                  Before You Begin

                  The IPHC profile must exist.

                  SUMMARY STEPS

                    1.    enable

                    2.    configure terminal

                    3.    iphc-profile profile-name

                    4.    non-tcp

                    5.    non-tcp contexts {absolute number-of-contexts | kbps-per-context kbps }

                    6.    rtp

                    7.    recoverable-loss {dynamic | packet-drops}

                    8.    refresh max-period {number-of-packets | infinite}

                    9.    refresh max-time {length-of-time | infinite}

                    10.    refresh rtp

                    11.    feedback

                    12.    maximum header max-header-size

                    13.    tcp

                    14.    Router(config-iphcp)# tcp contexts absolute 75

                    15.    end


                  DETAILED STEPS
                     Command or ActionPurpose
                    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 iphc-profile profile-name


                    Example:
                    Router(config)# iphc-profile profile3
                     

                    Specifies the IPHC profile and enters IPHC-profile configuration mode.

                    • Enter the IPHC profile name.
                     
                    Step 4 non-tcp


                    Example:
                    Router(config-iphcp)# non-tcp
                     

                    (Optional) Enables non-TCP header compression.

                     
                    Step 5 non-tcp contexts {absolute number-of-contexts | kbps-per-context kbps }


                    Example:
                    Router(config-iphcp)# non-tcp contexts absolute 75
                     

                    (Optional) Sets the number of contexts available for non-TCP header compression.

                    • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
                     
                    Step 6 rtp


                    Example:
                    Router(config-iphcp)# rtp
                     

                    (Optional) Enables RTP header compression.

                    Note   

                    This command automatically enables non-TCP header compression.

                     
                    Step 7 recoverable-loss {dynamic | packet-drops}


                    Example:
                    Router(config-iphcp)# recoverable-loss 5
                     

                    (Optional) Enables ECRTP.

                     
                    Step 8 refresh max-period {number-of-packets | infinite}


                    Example:
                    Router(config-iphcp)# refresh max-period 700
                     

                    (Optional) Sets the number of packets sent between full-header refresh occurrences.

                    • Enter the number of packets sent between full-header refresh occurrences, or enter the infinite keyword to indicate no limitation on the number of packets sent between full-header refresh occurrences.
                    Note   

                    Non-TCP header compression must be enabled first.

                     
                    Step 9 refresh max-time {length-of-time | infinite}


                    Example:
                    Router(config-iphcp)# refresh max-time infinite
                     

                    (Optional) Sets the amount of time to wait before a full-header refresh occurrence.

                    • Enter the length of time, in seconds, to wait before a full-header refresh occurrence, or enter the infinite keyword to indicate no limitation on the time between full-header refreshes.
                    Note   

                    Non-TCP header compression must be enabled first.

                     
                    Step 10 refresh rtp


                    Example:
                    Router(config-iphcp)# refresh rtp
                     

                    (Optional) Enables a context refresh for RTP header compression.

                    Note   

                    RTP header compression must be enabled first.

                     
                    Step 11 feedback


                    Example:
                    Router(config-iphcp)# feedback
                     

                    (Optional) Disables the context-status feedback messages from the interface or link.

                    Note   

                    TCP or non-TCP header compression must be enabled first.

                     
                    Step 12 maximum header max-header-size


                    Example:
                    Router(config-iphcp)# maximum header 75
                     

                    (Optional) Specifies the maximum size of the compressed IP header.

                    • Enter the maximum size of the compressed IP header, in bytes.
                    Note   

                    TCP or non-TCP header compression must be enabled first.

                     
                    Step 13 tcp


                    Example:
                    Router(config-iphcp)# tcp
                     

                    (Optional) Enables TCP header compression.

                     
                    Step 14 Router(config-iphcp)# tcp contexts absolute 75  

                    (Optional) Sets the number of contexts available for TCP header compression.

                    • Enter either the absolute keyword and the fixed number or the kbps-per-context keyword and the number of kbps to allow for each context.
                     
                    Step 15 end


                    Example:
                    Router(config-iphcp)# end
                     

                    (Optional) Exits IPHC-profile configuration mode.

                     

                    Attaching the IPHC Profile

                    You can attach the IPHC profile (either an ietf IPHC profile or a van-jacobson IPHC profile) to an interface, a subinterface, or a Frame Relay PVC.

                    Choose one of the following:

                    Attaching an IPHC Profile to an Interface

                    To attach an IPHC profile to an interface or subinterface, complete the following steps.

                    Before You Begin
                    • The IPHC profile must exist.
                    • IP must be enabled on the interface or subinterface.
                    • The type of encapsulation in use on the interface or subinterface must support header compression. Two types of encapsulation that typically support header compression are PPP and HDLC encapsulation.
                    • Header compression must not already be enabled.
                    • The interface or subinterface must have sufficient memory.
                    SUMMARY STEPS

                      1.    enable

                      2.    configure terminal

                      3.    interface type number [name-tag]

                      4.    iphc-profile profile-name

                      5.    end


                    DETAILED STEPS
                       Command or ActionPurpose
                      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 [name-tag]


                      Example:
                      Router(config)# interface fastethernet0
                       

                      Configures an interface type and enters interface configuration mode.

                      • Enter the interface type and the interface number.
                       
                      Step 4 iphc-profile profile-name


                      Example:
                      Router(config-if)# iphc-profile profile1
                       

                      Attaches the IPHC profile to the interface.

                      • Enter the IPHC profile to be attached to the interface specified in Step 3 .
                       
                      Step 5 end


                      Example:
                      Router(config-if)# end
                       

                      (Optional) Exits IPHC-profile configuration mode.

                       

                      Attaching an IPHC Profile to a Frame Relay PVC

                      To attach an IPHC profile to a Frame Relay PVC, complete the following steps.

                      Before You Begin
                      • The IPHC profile must exist.
                      • On a network that is using Frame Relay encapsulation, IPHC profiles are supported only in the Frame Relay map-class infrastructure.
                      SUMMARY STEPS

                        1.    enable

                        2.    configure terminal

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

                        4.    frame-relay iphc-profile profile-name

                        5.    exit

                        6.    interface type number [name-tag]

                        7.    encapsulation frame-relay

                        8.    ip address ip-address mask

                        9.    frame-relay interface-dlci dlci

                        10.    class name

                        11.    end


                      DETAILED STEPS
                         Command or ActionPurpose
                        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 mapclass1
                         

                        Creates a map class and enters static map class configuration mode.

                        • Enter the Frame Relay map class name.
                         
                        Step 4 frame-relay iphc-profile profile-name


                        Example:
                        Router(config-map-class)# frame-relay iphc-profile profile2
                         

                        Attaches the IPHC profile to the Frame Relay map class.

                        • Enter the IPHC profile to be attached to the Frame Relay map class created in Step 3 .
                         
                        Step 5 exit


                        Example:
                        Router(config-map-class)# exit
                         

                        Exits static map class configuration mode.

                         
                        Step 6 interface type number [name-tag]


                        Example:
                        Router(config)# interface serial2/0
                         

                        Configures an interface type and enters interface configuration mode.

                        • Enter the interface type and the interface number.
                         
                        Step 7 encapsulation frame-relay


                        Example:
                        Router(config-if)# encapsulation frame-relay
                         

                        Enables Frame Relay encapsulation on the interface.

                         
                        Step 8 ip address ip-address mask


                        Example:
                        Router(config-if)# ip address 209.165.200.225 255.255.255.224
                         

                        Sets a primary IP address for an interface.

                        • Enter the IP address and mask for the associated IP subnet.
                         
                        Step 9 frame-relay interface-dlci dlci


                        Example:
                        Router(config-if)# frame-relay interface-dlci 100
                         

                        Assigns a data-link connection identifier (DLCI) to a specified Frame Relay interface on the router or access server and enters Frame Relay DLCI configuration mode.

                        • Enter the DLCI number to be used on the specified interface.
                         
                        Step 10 class name


                        Example:
                        Router(config-fr-dlci)# class mapclass1
                         

                        Associates a map class with a specified DLCI.

                        • Enter the name of the map class to associate with the specified DLCI.
                         
                        Step 11 end


                        Example:
                        Router(config-fr-dlci)# end
                         

                        (Optional) Exits Frame Relay DLCI configuration mode.

                         

                        Displaying the IPHC Profile Statistics

                        In this task, you can display statistical information about the IPHC profiles that you have created and configured. Displaying the IPHC profile statistics allows you to confirm that the IPHC profile is configured as you intended.

                        Information reported includes the IPHC profile name and profile type, the type of header compression enabled, whether any optional header compression features (such as the number of contexts) are enabled, and the name of the interface to which the IPHC profile is attached (if applicable).

                        To display the IPHC profile statistics, complete the following steps.

                        Before You Begin

                        The IPHC profile must exist.

                        SUMMARY STEPS

                          1.    enable

                          2.    show iphc-profile [profile-name]

                          3.    end


                        DETAILED STEPS
                           Command or ActionPurpose
                          Step 1 enable


                          Example:
                          Router> enable
                           

                          Enables privileged EXEC mode.

                          • Enter your password if prompted.
                           
                          Step 2 show iphc-profile [profile-name]


                          Example:
                          Router# show iphc-profile profile1
                           

                          Displays configuration information for one or more IPHC profiles.

                          • (Optional) Enter the name of the IPHC profile you want to display. If you do not specify an IPHC profile name, all IPHC profiles are displayed.
                           
                          Step 3 end


                          Example:
                          Router# end
                           

                          (Optional) Exits privileged EXEC mode.

                           

                          Configuration Examples for Using IPHC Profiles

                          Example Creating an IPHC Profile

                          In the following example, a van-jacobson IPHC profile called profile1 has been created.

                          Router> enable
                          Router# configure terminal
                          Router(config)# iphc-profile profile1 van-jacobson
                          Router(config-iphcp)# end
                          
                          
                                

                          In the following example, an ietf IPHC profile called profile2 has been created.

                          Router> enable
                          Router# configure terminal
                          Router(config)# iphc-profile profile2 ietf
                          Router(config-iphcp)# end

                          Example Enabling TCP Header Compression

                          In the following example, TCP header compression has been enabled in a van-jacobson IPHC profile called profile1. Additionally, the number of TCP contexts has been set to 25.

                          Router> enable
                          Router# configure terminal
                          Router(config)# iphc-profile profile1
                          Router(config-iphcp)# tcp
                          Router(config-iphcp)# tcp contexts absolute 25
                          Router(config-iphcp)# end

                          Example Enabling Non-TCP Header Compression

                          In the following example, RTP header compression has been enabled in an ietf IPHC profile called profile2. Additionally, ECRTP has been enabled with the recoverable-loss command, and the size of the compressed IP header has been set to 75 bytes.

                          Router> enable
                          Router# configure terminal
                          Router(config)# iphc-profile profile2
                          Router(config-iphcp)# rtp
                          Router(config-iphcp)# recoverable-loss 5
                          Router(config-iphcp)# maximum header 75
                          Router(config-iphcp)# end
                          
                          
                              

                          Example Attaching the IPHC Profile

                          In the following example, an IPHC profile called profile1 is attached to serial interface 0.

                          Router> enable
                          Router# configure terminal
                          Router(config)# interface serial0
                          Router(config-if)# iphc-profile profile1
                          Router(config-if)# end
                          
                          
                                

                          In the following example, an IPHC profile called profile2 is attached to a Frame Relay map class called mapclass1.

                          Router> enable
                          Router# configure terminal
                          Router(config)# map-class frame-relay mapclass1
                          Router(config-map-class)# frame-relay iphc-profile profile2
                          Router(config-map-class)# exit
                          Router(config)# interface serial2/0
                          Router(config-if)# encapsulation frame-relay
                          Router(config-if)# ip address 209.165.200.225 255.255.255.224
                          Router(config-if)# frame-relay interface-dlci 100
                          Router(config-fr-dlci)# class mapclass1
                          Router(config-fr-dlci)# end

                          Example Reporting IPHC Profile Statistics

                          The following is sample output from the show iphc-profile command. In this output, information about two IPHC profiles, profile21 and 20, is displayed.

                          Router# show iphc-profile
                          IPHC Profile "profile21"
                          Type: VJ
                            Compressing: TCP 
                            Contexts   : TCP fixed at 150 
                            Controlled interfaces: (1)
                              Se3/1
                          IPHC Profile "profile20"
                          Type: IETF
                            Compressing: TCP NON-TCP (RTP)
                            Contexts   : TCP 1 for each 0 kbits NON-TCP 1 for each 0 kbits 
                            Refresh    : NON-TCP and RTP every 5 seconds or 256 packets
                            Controlled interfaces: (1)
                              Se3/0
                          
                          
                              

                          Additional References

                          The following sections provide references related to IPHC profiles.

                          Related Documents

                          Related Topic

                          Document Title

                          Cisco IOS commands

                          Cisco IOS Master Commands List, All Releases

                          QoS commands: complete command syntax, command modes, command history, defaults, usage guidelines, and examples

                          Cisco IOS Quality of Service Solutions Command Reference

                          QoS functionality overview

                          "Quality of Service Overview" module

                          Header compression overview

                          "Header Compression" module

                          RTP header compression

                          "Configuring RTP Header Compression" module

                          TCP header compression

                          "Configuring TCP Header Compression" module

                          Class-based RTP and TCP header compression

                          "Configuring Class-Based RTP and TCP Header Compression" module

                          Standards

                          Standard

                          Title

                          No new or modified standards are supported, and support for existing standards has not been modified.

                          --

                          MIBs

                          MIB

                          MIBs Link

                          No new or modified MIBs are supported, and support for existing MIBs has not been modified.

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

                          http:/​/​www.cisco.com/​go/​mibs

                          RFCs

                          RFC

                          Title

                          RFC 1144

                          Compressing TCP/IP Headers for Low-Speed Serial Links

                          RFC 2507

                          IP Header Compression

                          RFC 2508

                          Compressing IP/UDP/RTP Headers for Low-Speed Serial Links

                          RFC 3544

                          IP Header Compression over PPP

                          RFC 3545

                          Enhanced Compressed RTP (CRTP) for Links with High Delay, Packet Loss and Reordering

                          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 Configuring Header Compression Using IPHC Profiles

                          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 3 Feature Information for Configuring Header Compression Using IPHC Profiles

                          Feature Name

                          Releases

                          Feature Information

                          IPHC Profiles

                          12.4(9)T

                          The IPHC Profiles feature allows you to configure header compression in a kind of template ("profile") and to apply the profile to interfaces, subinterfaces, or Frame Relay PVCs.

                          The following commands were introduced by this feature: feedback, iphc-profile, maximum header, non-tcp, non-tcp contexts, recoverable-loss, refresh max-period, refresh max-time, refresh rtp, rtp, show iphc-profile, tcp, tcp contexts.