PPP over Ethernet Client

The PPP over Ethernet Client feature provides PPP over Ethernet (PPPoE) client support on routers.

PPPoE is a commonly used application in the deployment of digital subscriber lines (DSLs). The PPP over Ethernet Client feature expands PPPoE functionality by providing support for PPPoE on the client and the server.

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 PPP over Ethernet Client

PPP connections must be established between two endpoints over a serial link.

Restrictions for PPPoE Client

  • For PPPoE over ATM, one permanent virtual circuit (PVC) supports multiple PPPoE clients, allowing multiple PPPoE sessions to run concurrently on the same PVC. An ATM PVC is allowed to be a member of several dialer pools as long as the dialer pool number is unique.

  • For PPPoE, each PPPoE client must use a separate dialer interface and a separate dialer pool.

  • For the PPPoE--Max-Payload Support on Client feature the physical interface should support a maximum transmission unit (MTU) greater than 1500.

  • For the PPPoE--Max-Payload Support on Client feature, appropriate configuration is required on the Broadband Remote Access Server (BRAS). For more information, see the "PPP-Max-Payload and IWF PPPoE Tag Support" module.

Information About PPP over Ethernet Client

PPPoE Client Network Topology

The PPP over Ethernet Client feature provides PPPoE client support on routers on customer premises. Before the introduction of this feature, Cisco IOS software supported PPPoE on the access server side only. The figure below shows the typical network topology for configuring a PPPoE client on an Ethernet interface (E1 interface).

Figure 1. Typical Network Topology for PPPoE Deployment

PPPoE Client Support on ATM PVCs and Ethernet Interfaces

The PPPoE Client feature provides PPPoE client support on ATM PVCs and Ethernet interfaces. A dialer interface must be used for cloning virtual access.

Prior to Cisco IOS Release 12.4(15)T, one ATM PVC supported one PPPoE client. With the introduction of the Multiple PPPoE Client feature in Cisco IOS Release 12.4(15)T, one ATM PVC supports multiple PPPoE clients, allowing second line connection and redundancy. Multiple PPPoE clients can run concurrently on different PVCs, but each PPPoE client must use a separate dialer interface and a separate dialer pool.

Multiple PPPoE client sessions can be configured on an Ethernet interface, but each session must use a separate dialer interface and a separate dialer pool.

PPPoE--Max-Payload Support on Client

PPPoE, as described in RFC 2516, mandates a maximum negotiated Maximum Receive Unit (MRU) of 1492. This means that a PPPoE data packet cannot accommodate more than 1492 bytes of payload. To overcome this limitation, the client can use the PPP-Max-Payload tag (defined in RFC 4638) and negotiate a higher MRU with the Broadband Remote Access Server (BRAS). Use the pppoe-client ppp-max-payload command to send the PPP Max-Payload tag in PPPoE control packets to negotiate a higher MRU. A PPP Max-Payload tag allows a PPPoE client to override the MRU of 1492 by providing a maximum size for the PPP payload in both the sending and receiving directions.

The PPPoE client sends the PPPoE Max-Payload tag in a PPPoE Active Discovery Initiation (PADI) packet and if the PPPoE server can support a Maximum Transmission Unit (MTU)/Maximum Receive Unit (MRU) higher than 1492 octets, it responds with an echo of the clients tag in the PPPoE Active Discovery Offer (PADO) packet. The client sends the same tag in the PPPoE Active Discovery Request (PADR), and the server echoes the client tag in a PPPoE Active Discovery Session-confirmation (PADS) packet.

The pppoe-client ppp-max-payload command can only be configured when the PPPoE client dialer configuration is done. When the pppoe-client ppp-max-payload command is configured without the dialer configuration, an error message is displayed. If the dialer configuration is removed, the PPP max-payload configuration is also removed.

PPP over Ethernet Client Session Initiation

A PPPoE session is initiated by the PPPoE client. If the session has a timeout or is disconnected, the PPPoE client will immediately attempt to reestablish the session.

The following steps describe the exchange of packets that occurs when a PPPoE client initiates a PPPoE session:

  1. The client broadcasts a PPPoE active discovery initiation (PADI) packet.

  2. When the access concentrator receives a PADI packet that it can serve, it replies by sending a PPPoE active discovery offer (PADO) packet to the client.

  3. Because the PADI packet was broadcast, the host may receive more than one PADO packet. The host looks through the PADO packets it receives and chooses one. The choice can be based on the access concentrator name or on the services offered. The host then sends a single PPPoE active discovery request (PADR) packet to the access concentrator that it has chosen.

  4. The access concentrator responds to the PADR packet by sending a PPPoE active discovery session-confirmation (PADS) packet. At this point, a virtual access interface is created that will then negotiate PPP and the PPPoE session will run on this virtual access.

If a client does not receive a PADO packet for a PADI packet already received, the client sends out a PADI packet at predetermined intervals. That interval length is doubled for every successive PADI packet that does not evoke a response, until the interval reaches the configured maximum.

If PPP negotiation fails or the PPP line protocol is brought down for any reason, the PPPoE session and the virtual access will be brought down and the client will wait for a predetermined number of seconds before trying to establish another PPPoE session.

How to Configure a PPPoE Client

Configuring a PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T

Perform the following tasks to configure a PPPoE client:

Enabling PPPoE in a VPDN Group

Perform this task to enable PPPoE in a virtual private dial-up network (VPDN) group.


Note

This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

>
SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    vpdn enable

    4.    vpdn-group name

    5.    request-dialin

    6.    protocol pppoe

    7.    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 vpdn enable


    Example:
    Router(config)# vpdn enable
     

    Enables virtual private dialup networking.

     
    Step 4 vpdn-group name


    Example:
    Router(config)# vpdn-group group1
     

    Associates a VPDN group with a customer or a VPDN profile and enters VPDN group configuration mode.

     
    Step 5 request-dialin


    Example:
    Router(config-vpdn)#
 request-dialin
     

    Creates a request-dialin VPDN subgroup and enters the VPDN request dialin configuration mode.

     
    Step 6 protocol pppoe


    Example:
    Router(config-vpdn-req-in)#
 protocol pppoe
     

    Enables the VPDN subgroup to establish PPPoE sessions.

     
    Step 7 end


    Example:
    Router(config-vpdn-req-in)#
 end
     

    Exits VPDN request dialin configuration mode and returns to privileged EXEC mode.

     

    Configuring a PPPoE Client on an ATM PVC

    Perform this task to configure a PPPoE client on an ATM PVC.

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    interface atm number

      4.    pvc [name] vpi / vci

      5.    pppoe-client dial-pool-number number

      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 interface atm number


      Example:
      Router(config)# interface atm 0
       

      Configures an ATM interface.

       
      Step 4 pvc [name] vpi / vci


      Example:
      Router(config-if)# pvc 1/100
       

      Creates an ATM PVC and enters ATM virtual circuit configuration.

       
      Step 5 pppoe-client dial-pool-number number


      Example:
      Router(config-if-atm-vc)# pppoe-client dial-pool-number 1
       

      Configures the PPPoE client and specifies the dialer interface to use for cloning on the PVC.

       
      Step 6 end


      Example:
      Router(config-if-atm-vc)#
 end
       

      Returns to privileged EXEC mode.

       
      What to Do Next


      Note

      If you make any changes to the PVC configuration after the PPPoE client session is established, the session is automatically terminated and reestablished.

      Configuring a PPPoE Client on an Ethernet Interface

      Perform this task to configure a PPPoE client on an Ethernet interface.

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    interface ethernet number

        4.    pppoe-client dial-pool-number number

        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 ethernet number


        Example:
        Router(config)# interface ethernet 0
         

        Configures an Ethernet interface and enters interface configuration mode.

         
        Step 4 pppoe-client dial-pool-number number


        Example:
        Router(config-if)#
 pppoe-client dial-pool-number 1
         

        Configures the PPPoE client and specifies the dialer interface to use for cloning.

         
        Step 5 end


        Example:
        Router(config-if)# end
         

        Returns to privileged EXEC mode.

         

        Configuring the Dialer Interface

        Perform this task to configure the dialer interface to be used for cloning on the PVC.

        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    interface dialer number

          4.    mtu bytes

          5.    encapsulation ppp

          6.    ip address negotiated

          7.    dialer pool number

          8.    dialer-group group-number

          9.    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 dialer number


          Example:
          Router(config)# interface dialer 1
           

          Configures a dialer interface.

           
          Step 4 mtu bytes


          Example:
          Router(config-if)# mtu 1492
           

          Adjusts the maximum packet size or maximum transmission unit (MTU) size. The range is from 64 to 17940.

          Note   

          Cisco recommends that you set the MTU to 1492 bytes. This value accommodates a PPPoE header encapsulation of 8 bytes in the Ethernet frame payload.

           
          Step 5 encapsulation ppp


          Example:
          Router(config-if)# encapsulation ppp
           

          Sets the encapsulation type of the interface to Point-to-Point Protocol.

           
          Step 6 ip address negotiated


          Example:
          Router(config-if)# ip address negotiated
           

          Specifies that the IP address for the interface be obtained via PPP/IP Control Protocol (PPP/IPCP) address negotiation.

           
          Step 7 dialer pool number


          Example:
          Router(config-if)#
 dialer pool 1
           

          Specifies the dialing pool to use to connect to a specific destination subnetwork.

           
          Step 8 dialer-group group-number


          Example:
          Router(config-if)#
 dialer-group 1
           

          Configures an interface to belong to a specific dialing group.

           
          Step 9 end


          Example:
          Router(config-if)# end
           

          Exits interface configuration and returns to privileged EXEC mode.

           

          Clearing PPPoE Client Sessions

          Perform this task to clear PPPoE client sessions.


          Note

          This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

          >
          SUMMARY STEPS

            1.    enable

            2.    clear vpdn tunnel pppoe


          DETAILED STEPS
             Command or ActionPurpose
            Step 1 enable


            Example:
            Router> enable
             

            Enables privileged EXEC mode.

            • Enter your password if prompted.

             
            Step 2 clear vpdn tunnel pppoe


            Example:
            Router# clear vpdn tunnel pppoe
             

            Terminates the PPPoE client session and causes the PPPoE client to try to reestablish the session immediately.

             
            What to Do Next


            Note

            To terminate a PPPoE client session, use the no pppoe-client dial-pool-number command in interface configuration mode or interface-ATM-VC configuration mode.

            Verifying the PPPoE Client

            Perform this task to verify PPPoE client configuration.

            Before You Begin

            This task assumes that the PPPoE client has been configured.

            SUMMARY STEPS

              1.    enable

              2.    show vpdn

              3.    show vpdn session packet

              4.    show vpdn session all

              5.    show vpdn tunnel


            DETAILED STEPS
               Command or ActionPurpose
              Step 1 enable


              Example:
              Router> enable
               

              Enables privileged EXEC mode.

              • Enter your password if prompted.

               
              Step 2 show vpdn


              Example:
              Router# show vpdn
               

              Displays information about the active Layer 2 Forwarding (L2F) protocol tunnel and L2F message identifiers in a VPDN.

               
              Step 3 show vpdn session packet


              Example:
              Router# show vpdn session packet
               

              Displays PPPoE session statistics.

               
              Step 4 show vpdn session all


              Example:
              Router# show vpdn session all
               

              Displays PPPoE session information for each session ID.

               
              Step 5 show vpdn tunnel


              Example:
              Router# show vpdn tunnel
               

              Displays PPPoE session count for the tunnel.

               

              Troubleshooting PPPoE Client Sessions

              Perform this task to troubleshoot the PPPoE client.


              Note

              This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

              SUMMARY STEPS

                1.    enable

                2.    debug vpdn pppoe-data

                3.    debug vpdn pppoe-errors

                4.    debug vpdn pppoe-events

                5.    debug vpdn pppoe-packets


              DETAILED STEPS
                 Command or ActionPurpose
                Step 1 enable


                Example:
                Router> enable
                 

                Enables privileged EXEC mode.

                • Enter your password if prompted.

                 
                Step 2 debug vpdn pppoe-data


                Example:
                Router# debug vpdn pppoe-data
                 

                Displays PPPoE session data packets.

                 
                Step 3 debug vpdn pppoe-errors


                Example:
                Router# debug vpdn pppoe-errors
                 

                Displays PPPoE protocol errors that prevent a session from being established or errors that cause an established session to be terminated.

                 
                Step 4 debug vpdn pppoe-events


                Example:
                Router# debug vpdn pppoe-events
                 

                Displays PPPoE protocol messages about events that are part of normal session establishment or shutdown.

                 
                Step 5 debug vpdn pppoe-packets


                Example:
                Router# debug vpdn pppoe-packets
                 

                Displays each PPPoE protocol packet exchanged.

                 

                Configuring a PPPoE Client in Cisco IOS Release 12.2(13)T 12.4T and Later Releases

                Configuring a PPPoE Client on an ATM PVC

                Perform this task to configure a PPPoE client on an ATM PVC.

                SUMMARY STEPS

                  1.    enable

                  2.    configure terminal

                  3.    interface atm number

                  4.    pvc [name] vpi / vci

                  5.    pppoe-client dial-pool-number number

                  6.    pppoe-client ppp-max-payload max-value

                  7.    end


                DETAILED STEPS
                   Command or ActionPurpose
                  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 interface atm number


                  Example:
                  Device(config)# interface atm 0
                   

                  Configures an ATM interface.

                   
                  Step 4 pvc [name] vpi / vci


                  Example:
                  Device(config-if)# pvc 1/100
                   

                  Creates an ATM PVC and enters ATM virtual circuit configuration.

                   
                  Step 5 pppoe-client dial-pool-number number


                  Example:
                  Device(config-if-atm-vc)# pppoe-client dial-pool-number 1
                   

                  Configures the PPPoE client and specifies the dialer interface to use for cloning on the PVC.

                  Note   

                  If Cisco IOS Release 12.4(15)T or a later release is running, you can configure multiple PPPoE clients on the same PVC. For earlier releases, one PVC supports only one PPPoE client.

                   
                  Step 6 pppoe-client ppp-max-payload max-value


                  Example:
                  Device(config-if-atm-vc)#
 
pppoe-client ppp-max-payload 1500
                   

                  Configures the PPPoE client to send a PPP Max-Payload tag in PPPoE control packets.

                   
                  Step 7 end


                  Example:
                  Device(config-if-atm-vc)#
 
end
                   

                  Exits ATM virtual circuit configuration mode and returns to privileged EXEC mode.

                   
                  What to Do Next


                  Note

                  If you make any changes to the PVC configuration after the PPPoE client session is established, the session is automatically terminated and reestablished.

                  Configuring a PPPoE Client on an Ethernet Interface

                  Perform this task to configure a PPPoE client on an Ethernet interface.

                  SUMMARY STEPS

                    1.    enable

                    2.    configure terminal

                    3.    interface ethernet number

                    4.    pppoe-client dial-pool-number number

                    5.    pppoe-client ppp-max-payload max-value

                    6.    end


                  DETAILED STEPS
                     Command or ActionPurpose
                    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 interface ethernet number


                    Example:
                    Device(config)# interface ethernet 0
                     

                    Configures an Ethernet interface.

                     
                    Step 4 pppoe-client dial-pool-number number


                    Example:
                    Device(config-if)#
 pppoe-client dial-pool-number 1
                     

                    Configures the PPPoE client and specifies the dialer interface to use for cloning. You can configure multiple PPPoE clients on the same PVC.

                     
                    Step 5 pppoe-client ppp-max-payload max-value


                    Example:
                    Device(config-if)#
pppoe-client ppp-max-payload 1500
                     

                    Configures the PPPoE client to send a PPP Max-Payload tag in PPPoE control packets.

                     
                    Step 6 end


                    Example:
                    Device(config-if)#
 
end
                     

                    Exits interface configuration mode and returns to privileged EXEC mode.

                     

                    Configuring a PPPoE Client on an Ethernet Subinterface

                    Perform this task to configure a PPPoE client on an Ethernet subinterface.

                    SUMMARY STEPS

                      1.    enable

                      2.    configure terminal

                      3.    interface ethernet number

                      4.    encap dot1Q vlan-id [native]

                      5.    pppoe-client dial-pool-number number

                      6.    pppoe-client ppp-max-payload max-value

                      7.    end


                    DETAILED STEPS
                       Command or ActionPurpose
                      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 interface ethernet number


                      Example:
                      Device(config)# interface ethernet 0/0.10
                       

                      Configures an Ethernet subinterface, and enters Ethernet subinterface mode.

                       
                      Step 4 encap dot1Q vlan-id [native]


                      Example:
                      Device(config-subif)# encap dot1Q 10
                       

                      Enables IEEE 802.1Q encapsulation of traffic on a specified subinterface.

                       
                      Step 5 pppoe-client dial-pool-number number


                      Example:
                      Device(config-subif)#
 pppoe-client dial-pool-number 1
                       

                      Configures the PPPoE client and specifies the dialer interface to use for cloning.

                       
                      Step 6 pppoe-client ppp-max-payload max-value


                      Example:
                      Device(config-subif)#
 
pppoe-client ppp-max-payload 1500
                       

                      Configures the PPPoE client to send a PPP Max-Payload tag in PPPoE control packets.

                       
                      Step 7 end


                      Example:
                      Device(config-subif)#
 
end
                       

                      Exits subinterface configuration mode and returns to privileged EXEC mode.

                       

                      Configuring the Dialer Interface

                      Perform this task to configure the dialer interface to be used for cloning on the PVC.

                      SUMMARY STEPS

                        1.    enable

                        2.    configure terminal

                        3.    interface dialer number

                        4.    mtu bytes

                        5.    encapsulation ppp

                        6.    ip address negotiated

                        7.    dialer pool number

                        8.    dialer-group group-number

                        9.    end


                      DETAILED STEPS
                         Command or ActionPurpose
                        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 interface dialer number


                        Example:
                        Device(config)# interface dialer 1
                         

                        Configures a dialer interface.

                         
                        Step 4 mtu bytes


                        Example:
                        Device(config-if)# mtu 1492
                         

                        Adjusts the maximum packet size or MTU size.

                        Note   

                        Cisco recommends that you set the MTU to 1492 bytes. This value accommodates a PPPoE header encapsulation of 8 bytes in the Ethernet frame payload.

                         
                        Step 5 encapsulation ppp


                        Example:
                        Device(config-if)# encapsulation ppp
                         

                        Sets the encapsulation type of the interface to the Point-to-Point protocol.

                         
                        Step 6 ip address negotiated


                        Example:
                        Device(config-if)# ip address negotiated
                         

                        Specifies that the IP address for the interface is obtained via PPP/IPCP address negotiation.

                         
                        Step 7 dialer pool number


                        Example:
                        Device(config-if)#
 dialer pool 1
                         

                        Specifies the dialing pool to use to connect to a specific destination subnetwork.

                         
                        Step 8 dialer-group group-number


                        Example:
                        Device(config-if)#
 dialer-group 1
                         

                        Configures an interface to belong to a specific dialing group.

                         
                        Step 9 end


                        Example:
                        Device(config-if)# end
                         

                        Returns to privileged EXEC mode.

                         

                        Clearing PPPoE Client Sessions

                        Perform this task to clear PPPoE client sessions.


                        Note

                        This task applies only to Cisco IOS Release 12.2(13)T and later releases.

                        >
                        SUMMARY STEPS

                          1.    enable

                          2.    clear pppoe {interface type number [vc {[vpi/]vci | vc-name}] | rmac mac-address | all}


                        DETAILED STEPS
                           Command or ActionPurpose
                          Step 1 enable


                          Example:
                          Device> enable
                           

                          Enables privileged EXEC mode.

                          • Enter your password if prompted.

                           
                          Step 2 clear pppoe {interface type number [vc {[vpi/]vci | vc-name}] | rmac mac-address | all}


                          Example:
                          Device# clear pppoe all
                           

                          Clears the PPPoE client session and causes the PPPoE client to try immediately to reestablish the session.

                           
                          What to Do Next


                          Note

                          To permanently terminate a PPPoE client session, use the no pppoe-client dial-pool-numbercommand in interface configuration mode or interface-ATM-VC configuration mode.

                          Verifying the PPPoE Client

                          Perform this task to verify PPPoE client configuration.


                          Note

                          This task applies only to Cisco IOS Release 12.2(13)T and later releases.

                          SUMMARY STEPS

                            1.    enable

                            2.    show pppoe session [all | packets]


                          DETAILED STEPS
                             Command or ActionPurpose
                            Step 1 enable


                            Example:
                            Device> enable
                             

                            Enables privileged EXEC mode.

                            • Enter your password if prompted.

                             
                            Step 2 show pppoe session [all | packets]


                            Example:
                            Device# show pppoe session
                             

                            Displays information about currently active PPPoE sessions.

                             

                            Troubleshooting PPPoE Client Sessions

                            Perform this task to troubleshoot the PPPoE client.


                            Note

                            This task applies only to Cisco IOS Release 12.2(13)T and later releases.

                            SUMMARY STEPS

                              1.    enable

                              2.    debug pppoe {data | errors | events | packets}


                            DETAILED STEPS
                               Command or ActionPurpose
                              Step 1 enable


                              Example:
                              Device> enable
                               

                              Enables privileged EXEC mode.

                              • Enter your password if prompted.

                               
                              Step 2 debug pppoe {data | errors | events | packets}


                              Example:
                              Device# debug pppoe errors
                               

                              Displays debugging information for PPPoE sessions.

                               

                              Configuration Examples for PPPoE Client

                              Examples PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T

                              In the following example, a PPPoE client is configured on a PVC on the ATM interface 0. The PPPoE client uses the dialer interface 1 as its virtual access interface.

                              vpdn enable
vpdn-group 1
 request-dialin
  protocol pppoe
! 
interface atm0
 pvc 1/100
  pppoe-client dial-pool-number 1
!
interface dialer 1
 ip address negotiated
 dialer pool 1
 dialer-group 1
!

                              In the following example, two PPPoE client sessions are configured on an Ethernet interface. Each PPPoE client uses a separate dialer interface and a separate dialer pool.

                              vpdn enable
vpdn-group 1
 request-dialin
  protocol pppoe
! 
interface ethernet1/1
 pppoe-client dial-pool-number 1
 pppoe-client dial-pool-number 2
!
interface dialer 1
 ip address negotiated
 dialer pool 1
 dialer-group 1
!
interface dialer 2
 ip address negotiated
 dialer pool 2
 dialer-group 2

                              Examples PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases

                              The following example shows how to configure a PPPoE client on an Ethernet interface. Note that in Releases 12.2(13)T and later it is not necessary to configure a global VPDN group before configuring the PPPoE client. 

                              interface Ethernet 0
 pppoe-client dial-pool-number 1
 pppoe-client ppp-max-payload 1500
interface Dialer 1
 ip address negotiated
 dialer pool 1
 mtu 1492

                              The following example shows how to configure multiple PPPoE clients on an ATM VC. Note that in Releases 12.4(15)T or a later release, more than one PPPoE session is supported on a single PVC.

                              interface ATM0
 no ip address
 no ip mroute-cache
 no atm ilmi-keepalive
 pvc 4/20
  pppoe-client dial-pool-number 1
  pppoe-client dial-pool-number 2
  pppoe-client ppp-max-payload 1500
 !
end

                              Additional References

                              Related Documents

                              Related Topic

                              Document Title

                              Cisco IOS commands

                              Cisco IOS Master Commands List, All Releases

                              Broadband and DSL commands

                              Cisco IOS Broadband and DSL Command Reference

                              VPDN features

                              Cisco IOS VPDN Configuration Guide

                              VPDN and PPPoE commands

                              Cisco IOS Broadband Access Aggregation and DSL Command Reference

                              PPP over Frame Relay

                              Cisco IOS Wide-Area Networking Configuration Guide

                              Standards

                              Standard

                              Title

                              No new or modified standards are supported by this feature.

                              --

                              MIBs

                              MIB

                              MIBs Link

                              No new or modified MIBs are supported by this feature.

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

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

                              RFCs

                              RFC

                              Title

                              RFC 2516

                              A Method for Transmitting PPP over Ethernet (PPPoE)

                              RFC 4638

                              Accommodating a Maximum Transit Unit/Maximum Receive Unit (MTU/MRU) Greater Than 1492 in the Point-to-Point Protocol over Ethernet (PPPoE)

                              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 PPP over Ethernet Client

                              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 . An account on Cisco.com is not required.
                              Table 1 Feature Information for PPP over Ethernet Client

                              Feature Name

                              Releases

                              Feature Information

                              PPPoE--Max-Payload Support on Client

                              15.1(4)M

                              This feature supports the PPPoE client to send a PPP Max-Payload tag in PPPoE control packets. This feature is based on RFC 4638.

                              The following command was introduced or modified: pppoe-client ppp-max-payload.

                              PPP over Ethernet Client

                              12.2(2)T 12.2(13)T 12.4(15)T 15.0(1)M

                              This feature was introduced.

                              In Cisco IOS Release 12.2(13)T, PPPoE client functionality was separated from VPDN functionality, resulting in changes to PPPoE client configuration.

                              In the Cisco IOS Release 12.4(15)T, support was added for multiple PPPoE sessions per VC.

                              No new commands were introduced or modified.

                              PPP over Ethernet Subinterface

                              12.4(20)T

                              Support was added for PPPoE clients on Ethernet subinterfaces.