Cisco ASR 1000 Series Aggregation Services Routers

Table Of Contents

Configuring MPLS Layer 2 VPNs

Finding Feature Information

Contents

Overview of L2VPN Interworking

L2VPN Interworking Modes

Ethernet or Bridged Interworking

IP or Routed Interworking

Virtual Private LAN Services

Reverse Layer 2 Gateway Protocol

BPDUs Sent Out of R-L2GP Ports

BPDUs Received on R-L2GP Ports

BPDUs Received on L2 Protocol Forwarding PW

Restrictions for R-L2GP

Configuring the R-L2GP

Configuring the MST

Configuring an R-L2GP Instance

Attaching an R-L2GP Instance to a Port

Example: Configuring an R-L2GP

Configuring the Layer 2 Protocol Forwarding Virtual Private LAN Services Pseudowire between Two Redundant NPES

Verifying an R-L2GP Configuration

Prerequisites for Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

Example: Frame Relay-to-ATM Bridged Interworking on an ATM-PE Router

Example: Frame Relay-to-ATM Bridged Interworking on a Frame Relay-PE Router

Gigabit EtherChannel for Virtual Private Wire Service

Supported Modes

GEC Like-to-Like Mode

Any-to-GEC Mode

Restrictions for Gigabit EtherChannel for Virtual Private Wire Service

Configuring Gigabit EtherChannel for Virtual Private Wire Service

EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking

EtherChannel-to-EtherChannel over MPLS (Routed) Interworking

Example: GEC Like-to-Like (Routed) Interworking

Any-to-EtherChannel over MPLS (Bridged) Interworking

Any-to-EtherChannel over MPLS (Routed) Interworking

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Feature Information for Configuring MPLS Layer 2 VPNs

Glossary

Configuring MPLS Layer 2 VPNs

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First Published: March 29, 2012

The Frame Relay to Asynchronous Transfer Mode (ATM) Bridged Interworking feature provides interoperability between the Frame Relay attachment virtual circuit (VC) and the ATM attachment VC that are connected to different provider edge (PE) routers. The bridged encapsulation corresponding to the bridged (Ethernet) interworking mechanism is used to enable this interoperability. The Ethernet frames are carried through the MPLS network using Ethernet over MPLS (EoMPLS). The interworking function is performed in the PE routers connected to the Frame Relay attachment VC and the ATM attachment VC based on RFC 2684 and RFC 2427.

The xconnect support on Gigabit EtherChannel (GEC) Virtual Private Wire Service (VPWS) on ASR 1000 feature enables service providers to supply connectivity between customer sites with existing data link layer (Layer 2) networks by using a single, integrated, packet-based network infrastructure—a Cisco MPLS network. Instead of separate networks with separate network management environments, service providers can deliver Layer 2 connections over an MPLS backbone.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest information about features and caveats, see the release notes document pertaining to your platform and software release. To find information about the features documented in this module and to view a list of the releases in which each feature is supported, see the "Feature Information for Configuring MPLS Layer 2 VPNs" section.

Use the Cisco Feature Navigator to find information about platform support and Cisco IOS and Cisco Catalyst operating system software image support. To access the Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Contents

•Overview of L2VPN Interworking

•Virtual Private LAN Services

•Prerequisites for Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

•Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

•Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

•Gigabit EtherChannel for Virtual Private Wire Service

•Configuring Gigabit EtherChannel for Virtual Private Wire Service

•Additional References

•Feature Information for Configuring MPLS Layer 2 VPNs

•Glossary

Overview of L2VPN Interworking

Interworking is a transforming function that interconnects two heterogeneous attachment circuits (ACs). Several types of interworking functions exist. The function that is used depends on the AC type used, the type of data carried, and the level of functionality required. The two main Layer 2 Virtual Private Network (L2VPN) interworking functions supported in Cisco IOS XE software are bridged interworking and routed interworking.

Layer 2 (L2) transport over multiprotocol label switching (MPLS) and IP exists for ACs, such as Ethernet-to-Ethernet or Point-to-Point Protocol (PPP), Ethernet to VLAN, and Ethernet to Frame Relay. An interworking function facilitates translation between different L2 encapsulations.

L2VPN Interworking Modes

L2VPN interworking works in either Ethernet (bridged) mode or IP (routed) mode. You can specify the mode by issuing the interworking {ethernet | ip} command in the pseudowire-class configuration mode.

The interworking command causes the ACs to be terminated locally. The two keywords perform the following functions:

•The ethernet keyword causes Ethernet frames to be extracted from an AC and sent over the pseudowire. Ethernet end-to-end transmission is resumed. The AC frames that are not Ethernet are dropped. In the case of VLAN, the VLAN tag is removed, leaving an untagged Ethernet frame.

•The ip keyword causes IP packets to be extracted from an AC and sent over the pseudowire. The AC frames that do not contain IPv4 packets are dropped.

The following sections explain the Ethernet and IP interworking modes in detail.

Ethernet or Bridged Interworking

Ethernet interworking is also called bridged interworking. Ethernet frames are bridged across the pseudowire. The CE routers can natively bridge Ethernet traffic or can route traffic using a bridged encapsulation model, such as Bridge-group Virtual Interface (BVI) or Routed Bridge Encapsulation (RBE). The PE routers operate in the Ethernet like-to-like mode.

The Ethernet interworking mode offers the following services:

•LAN services—An example of this is an enterprise that has several sites, with some sites having Ethernet connectivity to the service provider (SP) network and others having Asynchronous Transfer Mode (ATM) connectivity. If the enterprise requires LAN connectivity to all its sites, traffic from the Ethernet or VLAN of one site can be sent through the IP/MPLS network and encapsulated as bridged traffic over an ATM VC of another site.

•Connectivity services—An example of this is an enterprise that has different sites running an Internal Gateway Protocol (IGP) that has incompatible procedures on broadcast and non broadcast links. This enterprise has several sites that run an IGP, such as Open Shortest Path First (OSPF) or Intermediate System-to-Intermediate System (IS-IS), between the sites. In this scenario, some of the procedures (such as route advertisement or designated router election) depend on the underlying L2 protocol and are different for a point-to-point ATM connection versus a broadcast Ethernet connection. Therefore, the bridged encapsulation over ATM can be used to achieve homogenous Ethernet connectivity between the CE routers running an IGP.

IP or Routed Interworking

IP interworking is also called routed interworking. The CE routers encapsulate the IP on the link between the CE router and the PE router. A new VC type is used to signal the IP pseudowire in MPLS. Translation between the L2 and IP encapsulations across the pseudowire is required. Special consideration needs to be given to the address resolution protocol operation and routing protocol operation, because these are handled differently on different L2 encapsulations.

The IP interworking mode is used to provide IP connectivity between sites, regardless of the L2 connectivity to these sites. It is different from a Layer 3 VPN because it is point-to-point in nature and the service provider does not maintain any routing information pertaining to customers.

Address resolution is encapsulation dependent as specified here:

•Ethernet uses Address Resolution Protocol (ARP)

•ATM uses inverse ARP

•PPP uses IP Control Protocol (IPCP)

Therefore, address resolution must be terminated on the PE router. Also, the end-to-end address resolution is not supported. Routing protocols operate differently over broadcast and point-to-point media. For Ethernet, the CE routers must either use static routing or configure the routing protocols to treat the Ethernet side as a point-to-point network.

In routed interworking, the IP packets that are extracted from the ACs are sent over the pseudowire. The pseudowire works in the IP Layer 2 transport (VC type 0x000B) like-to-like mode. The interworking function at the network service provider's (NSP) end completes the required adaptation based on the AC technology. The non-IPv4 packets are dropped.

In routed interworking, the following considerations must be kept in mind:

•ARP, inverse ARP, and IPCP are punted to the routing protocol.

Therefore, the PE router at the NSP end must provide the following address-resolution functionalities for the Ethernet and ATM and Frame Relay point-to-point subinterface attachment circuits:

–Ethernet—The PE device acts as a Proxy ARP server to all the ARP requests from the CE router. The PE router responds with the MAC address of its local interface.

–ATM and Frame Relay point-to-point subinterface—By default, inverse ARP does not run in the point-to-point Frame Relay or ATM subinterfaces. The IP address and subnet mask define the connected prefix; therefore, configuration is not required in the CE devices.

•Interworking requires that the MTUs in both the ACs must match for the pseudowire that is to come up. The default MTU in one AC must match the MTU of other AC.

Table 1 lists the range of MTUs that can be configured for different ACs.

Table 1 Range of MTUs for Different ACs

AC Type	Range of MTUs1 Supported
ATM	64 to 9216
Gigabit Ethernet	1500 to 9216
POS	64 to 9216
Fast Ethernet	1500 to 9216

1 The MTU configured on an AC must not exceed the MTU in the core network. This ensures that the traffic is not fragmented.

•The CE routers with Ethernet attachment VCs running OSPF must be configured with the ospfIfType option so that the OSPF protocol treats the underlying physical broadcast link as a P2P link.

Virtual Private LAN Services

Virtual Private LAN Service (VPLS) enables enterprises to link together their Ethernet-based LANs from multiple sites via the infrastructure provided by their service provider. From the enterprise perspective, the service provider's public network looks like one giant Ethernet LAN. For the service provider, VPLS provides an opportunity to deploy another revenue-generating service on top of their existing network without major capital expenditures. Operators can extend the operational life of equipment in their network.

Virtual Private LAN Services (VPLS) uses the provider core to join multiple attachment circuits together to simulate a virtual bridge that connects the multiple attachment circuits together. From a customer point of view, there is no topology for VPLS. All of the CE devices appear to connect to a logical bridge emulated by the provider core.

Reverse Layer 2 Gateway Protocol

Layer 2 Gateway Protocol (L2GP) is a recommended IEEE standard (802.1ah) to address the issues that arise when two independent, bridged domains are connected redundantly through an arbitrary number of links. L2GP defines how the forwarding gateways are selected, so that only redundant ports are blocked and there are no temporary loops. The transition should be at least the same speed in which STP L2GP resolves the the transient loop problem during the reconvergence because it does not require cooperation from the outside domain.

Reverse Layer 2 Gateway Protocol (R-L2GP) is a variation of an L2GP. In case of an R-L2GP, the pseudo information of the R-L2GP is transmitted by Network-facing Provider Edges (nPEs) instead of User Provider-Edges (uPEs). R-L2GP provides a mechanism to send out static preconfigured Bridge Protocol Data Units (BPDUs) on each ring access port of nPEs to stimulate a per-access ring instantiation of the protocol. R-L2GP enables the Provider Edges (PEs) to avoid the burden of running Multiple Instance Spanning Tree Protocol (MST) when multiple independent access networks that run MST connect to a pair of redundant PEs.

In order for this to work, the pair of nPEs are programmed to send out BPDUs on the access ring ports in such a way that they appear to be either:

•The root bridge itself (the bridge with the lowest bridge ID or priority).

•The bridge with the second lowest bridge ID or priority, and with a 0 cost path to the root.

Using R-L2GP, you can statically configure the BPDUs instead of the STP generate the BPDUs dynamically.

Figure 1 shows the topology of multiple-access networks connected to redundant nPEs.

Figure 1

Multiple-Access Networks Connected to Redundant nPEs

BPDUs Sent Out of R-L2GP Ports

An R-L2GP module in a route processor (RP) generates static preconfigured BPDUs, and sends them to uPEs via access ports, with the R-L2GP enabled.

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Note Only localy generated static BPDUs can be sent out to RL2GP ports.

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Figure 2 shows how a BPDU is forwarded to an R-L2GP port.

Figure 2 BPDU on an R-L2GP Port

BPDUs Received on R-L2GP Ports

On PE, only BPDUs with Topology Change Notification (TCN) bits on are punted to the R-L2GP and the STP module. If the PE is in a redundant setting, the corresponding BPDUs are is propagated to peer-redundant PE via the L2 protocol forwarding pseudowire (PW).

BPDUs Received on L2 Protocol Forwarding PW

The TCN BPDUs received from L2 protocol forwarding PW are punted to RP, and STP/R-L2GP process it and generate MAC flush.

Restrictions for R-L2GP

The restrictions for the R-L2GP feature are:

•R-L2GP is supported only on L2 bridge ports, and is not compatible with prestandard MST.

•All the access-side shall have the same MST instance, the same name and the same revision number configuration as nPEs.

•There is no configure error detection and recover mechanism for R-L2GP. Users are expected to configure R-L2GP and MSTP instance on CEs and nPEs correctly.

Configuring the R-L2GP

Since the R-L2GP configuration is bundled with the MST configuration, the above parameters can be recycled from the MSTI and MST region (currently only one MST region is supported on IOS) configurations. This section describes how to configure Reverse L2GP. It consists of the following sections:

•Configuring the MST

•Configuring an R-L2GP Instance

•Attaching an R-L2GP Instance to a Port

•Example: Configuring an R-L2GP

•Configuring the Layer 2 Protocol Forwarding Virtual Private LAN Services Pseudowire between Two Redundant NPES

Configuring the MST

Configuration of the MST must be done before configuring the R-L2GP and attaching the R-L2GP to a port.

SUMMARY STEPS

1. enable

2. configure terminal

3. spanning-tree mode mst

4. spanning-tree mst configuration

5. [no] name name

6. [no] revision version

7. [no] instance instance-id {vlans vlan-range}

DETAILED STEPS

	Command	Purpose
Step 1	enable Example: Router# enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	spanning-tree mode mst Example: Router(config)# spanning-tree mode mst.	Enables the MST mode.
Step 4	spanning-tree mst configuration Example: Router(config)# spanning-tree mst configuration	Enters the MST configuration submode.
Step 5	name name Example: Router(config-mst)# name Cisco	Sets the name of the MST region. Note All the nodes in the same region should be configured with the same MST name.
Step 6	revision version Example: Router(config-mst)# revision 5	Sets the revision number for the MST (802.1s) configuration. Note All the nodes in the same region should be configured with the same MST configure revision number.
Step 7	instance instance-id {vlans vlan-range} Example: Router(config-mst)# instance 2 vlans 1-100	Maps a VLAN or a group of VLANs to an MST instance.

Configuring an R-L2GP Instance

Perform the following steps to configure the R-L2GP Instance.

SUMMARY STEPS

1. enable

2. configure terminal

3. spanning-tree pseudo-information transmit indentifier

4. remote-id id

5. mst root

6. mst cost

DETAILED STEPS

	Command	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	spanning-tree pseudo-information transmit indentifier Example: Router(config)# spanning-tree pseudo-information transmit 46	Configures the Reverse-L2GP configuration on the interface or the untagged Ethernet Flow Point (EFP) port.
Step 4	remote-id id Example: Router(config-pseudo)# remote-id 53	Configures the remote R-L2GP instance ID that pairs with the specified R-L2GP instance ID.
Step 5	mst region-id root mac-address Example: Router(config-pseudo)# mst 0 root 32768 0000.0000.0001	Adds MST instances to R-L2GP instances and configures the MAC address and priority for MST instances. Note MST 0 has all the VLANs that have not been explicitly specified in other MST instances. MST 0 must be configured for each R-L2GP instance.
Step 6	mst region-id cost Example: Router(config-pseudo)# mst 1 cost 1	Adds the corresponding MST instance list to the R-L2GP instance and configures the R-L2GP path cost for the MST instance or multiple MST instances.

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Note To configure an R-L2GP on the Cisco ASR 1000 Series Aggregation Services Router, the remote-id configured on nPE1 must be the transmit identifier configured on nPE2, and vice versa, as show in Example: Configuring an R-L2GP.

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Attaching an R-L2GP Instance to a Port

SUMMARY STEPS

1. enable

2. configure terminal

3. interface gigabitethernet slot/port or interface tengigabitethernet slot/port

4. spanning-tree pseudo-information transmit indentifier

DETAILED STEPS

	Command	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	interface gigabitethernet slot/port or interface tengigabitethernet slot/port Example: Router(config)# interface gigabitethernet 4/1	Specifies Gigabit Ethernet or the 10 Gigabit Ethernet interface on the access side of the nPE to configure. Here: •slot/port—Specifies the location of the interface.
Step 4	spanning-tree pseudo-information transmit identifier Example: Router(config-if)# spanning-tree pseudo-information transmit 46	Configures the Reverse-L2GP configuration on the interface. Note The identifier should be the same as the one configured on the nPE.

Example: Configuring an R-L2GP

The following example shows how to configure an R-L2GP in a network comprising two nPEs.

Configuration example on nPE1:

enable

configure terminal

spanning-tree pseudo-information transmit 46

  remote-id 53

  mst 0 root 32768 0000.0000.0001

  mst 1 root 32768 0000.0000.0002

  mst 1 cost 1

  mst 2 root 32768 0000.0000.0003

exit

interface gigabitEthernet 2/1/0

   spanning-tree pseudo-information transmit 46

Configuration example on nPE2:

spanning-tree pseudo-information transmit 53

  remote-id 46

  mst 0 root 32768 0000.0000.0001

  mst 1 root 32768 0000.0000.0002

  mst 1 cost 1

  mst 2 root 32768 0000.0000.0003

interface gigabitEthernet 0/0/1

   spanning-tree pseudo-information transmit 53

Configuring the Layer 2 Protocol Forwarding Virtual Private LAN Services Pseudowire between Two Redundant NPES

SUMMARY STEPS

1. enable

2. configure terminal

3. l2 vfi vfi-name manual

4. vpn id vpn_id

5. bridge-domain bridge_id

6. forward permit l2protocol all

7. neighbor ip-address vc-id {encapsulation mpls |pw-class pw-class-name}

DETAILED STEPS

	Command	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	l2 vfi vfi-name manual Example: Router(config)# l2 vfi vfitest1 manual	Creates a Layer 2 Virtual Forwarding Instance (VFI) and enters the Layer 2 VFI manual configuration submode.
Step 4	vpn id vpn_id Example: Router(config-vfi)# vpn id 303	Sets or updates a VPN ID on a VPN routing and forwarding (VRF) instance.
Step 5	bridge-domain bridge_id Example: Router(config-vfi)# bridge-domain 100	Binds a service instance to a bridge domain instance.
Step 6	forward permit l2protocol all Example: Router(config-vfi)# forward permit l2protocol all	Defines the VPLS pseudowire that is used to transport bridge protocol data unit (BPDU) information between two network provider edge (N-PE) routers.
Step 7	neighbor ip-address vc-id {encapsulation mpls |pw-class pw-class-name} Example: Router(config-vfi)# neighbor 10.10.10.10 1 encapsulation mpls	Specifies the routers that should form a point-to-point Layer 2 virtual forwarding interface (VFI) connection.

Verifying an R-L2GP Configuration

The following examples show how to use the show commands to verify an R-L2GP configuration:

Router# show spanning-tree pseudo-information 46 configuration 

remote_id 53

 mst_region_id 0, port_count 2, update_flag 0x0

 mrecord 0x3AF841EC, mrec_count 3:

      msti 0: root_id 32768.0000.0000.0001, root_cost 0, update_flag 0x0

      msti 1: root_id 32769.0000.0000.0002, root_cost 1, update_flag 0x0

      msti 2: root_id 32770.0000.0000.0003, root_cost 0, update_flag 0x0

Router# show spanning-tree pseudo-information 1 interface GigabitEthernet3/0/3

Pseudo id 1:

        GigabitEthernet 2/1/0

        GigabitEthernet 0/0/1

Prerequisites for Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

Before you configure the Frame Relay Data Link Connection Identifier (DLCI)-to-ATM AAL5SNAP Bridged Interworking feature on a router, ensure that the following prerequisites are met:

•Enable frame-relay switching on the Frame Relay provider edge (PE) router.

•Customer edge (CE) routers must support Bridge-group Virtual Interface or Routed Bridge Encapsulation.

Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

This feature provides interoperability between the ATM attachment VC and Frame Relay attachment VC connected to different PE routers. This interworking uses the bridged encapsulation corresponding to the bridged (Ethernet) interworking mechanism. The Ethernet frames are carried through the MPLS network using Ethernet over MPLS (EoMPLS). This feature is configured only in the bridged mode and not in the routed mode.

Figure 3 shows the interworking function performed in the PE routers that are connected to the ATM attachment VC and the Frame Relay attachment VC.

Figure 3 Network Topology for Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

On the ATM PE router with interworking function, when traffic flows from the ATM segment to MPLS cloud, the bridged encapsulation (ATM and SNAP header) is discarded and the Ethernet frame is encapsulated with the labels required to go through the pseudowire using the VC type 5 (Ethernet). In the opposite direction, after the label disposition from the MPLS cloud, the Ethernet frames are encapsulated over AAL5SNAP using bridged encapsulation.

On the FR PE router with interworking function, when traffic flows from the FR segment to the MPLS cloud, the bridged encapsulation (Frame Relay and SNAP header) is discarded and the Ethernet frame is encapsulated with the labels required to go through the pseudowire, using the VC type 5 (Ethernet). In the opposite direction, after the label disposition from the MPLS cloud, the Ethernet frames are encapsulated over FR using bridged encapsulation.

The PE router automatically supports translation of both Cisco and IETF Frame Relay encapsulation types coming from the Customer edge (CE) router, but translates only to IETF when sending to the CE router. The Cisco CE router can handle the IETF encapsulation on receipt, even if it is configured to send Cisco encapsulation.

The following modes are supported:

•The ATM permanent virtual circuit (PVC) mode with the AAL5SNAP encapsulation type, and the existing Quality of Service (QoS) functionality for ATM PVCs.

•The Frame Relay DLCI mode, and the existing QoS functionality for Frame Relay.

PVC status signaling works the same way it does in the like-to-like case. The PE router reports the PVC status to the CE router, based on the availability of the pseudowire.

The attachment circuit maximum transmission unit (MTU) on both sides of the pseudowire must match when connected over MPLS. The non-AAL5 traffic (such as OAM cells) is punted to be processed at the RP level. A VC that is configured with OAM cell emulation on the ATM PE router (using the oam-ac emulation-enable command) can send end-to-end F5 loopback cells at configured intervals toward the CE router. When the pseudowire is down, an end-to-end F5 segment alarm indication signal (AIS) and remote defect indication (RDI) is sent from the PE router to the CE router.

Figure 4 shows the protocol stack for the Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking feature.

Figure 4 Protocol Stack for Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking

To configure the Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking feature on an ATM-PE router, perform the following steps:

SUMMARY STEPS

1. enable

2. configure terminal

3. no ip domain lookup

4. mpls label range minimum-value maximum-value [static minimum-static-value maximum-static-value]

5. mpls label protocol ldp

6. mpls ip default-route

7. mpls ldp graceful-restart

8. xconnect logging pseudowire status

9. pseudowire-class [pw-class-name]

10. encapsulation mpls

11. interworking ethernet

12. exit

13. interface loopback loopback-interface-number

14. ip address ip-address mask

15. exit

16. interface GigabitEthernet slot/subslot/port

17. ip address ip-address mask

18. negotiation auto

19. mpls ip

20. exit

21. interface atm slot/subslot/port

22. no ip address

23. atm clock internal

24. no atm enable-ilmi-trap

25. exit

26. interface atm slot/subslot/port [.subinterface-number {point-to-point}]

27. mtu bytes

28. no atm enable-ilmi-trap

29. pvc [name] vpi/vci l2transport

30. encapsulation encapsulation-type

31. xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name

32. exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	Router(config)# no ip domain lookup	Disables the IP domain naming system (DNS).
Step 4	mpls label range minimum-value maximum-value [static minimum-static-value maximum-static-value] Example: Router(config)# mpls label range 101 4000 static 4001 5001	Configures the range of local labels available for use with Multiprotocol Label Switching (MPLS) applications on packet interfaces.
Step 5	mpls label protocol ldp Example: Router(config)# mpls label protocol ldp	Specifies label distribution protocol (LDP) for the ATM-PE router.
Step 6	mpls ip default-route Example: Router(config)# mpls ip default-route	Enables the distribution of labels associated with the IP default route.
Step 7	mpls ldp graceful-restart Example: Router(config)# mpls ldp graceful-restart	Enables MPLS LDP graceful restart.
Step 8	xconnect logging pseudowire status Example: Router(config)# xconnect logging pseudowire status	Enables system logging (syslog) reporting of pseudowire status events.
Step 9	pseudowire-class [pw-class-name] Example: Router(config)# pseudowire-class atm-fr-bridged	Establishes a pseudowire class with a name that you specify, and enters the pseudowire class configuration mode.
Step 10	encapsulation mpls Example: Router(config-pw-class)# encapsulation mpls	Enables MPLS encapsulation on the interface.
Step 11	interworking ethernet Example: Router(config-pw-class)# interworking ethernet	Enables the L2VPN Ethernet interworking feature.
Step 12	exit	Exits the pseudowire class configuration mode.
Step 13	interface loopback loopback-interface-number Example: Router(config)# interface loopback 0	Specifies the loopback logical interface.
Step 14	ip address ip-address mask Example: Router(config-if)# ip address 44.1.1.2 255.255.255.255	Specifies the IP address for the Loopback interface.
Step 15	exit	Exits the interface configuration mode.
Step 16	interface GigabitEthernet slot/subslot/port Example: Router(config)# interface GigabitEthernet 0/0/1	Specifies the Gigabit Ethernet interface for the connection of the PE routers.
Step 17	ip address ip-address mask Example: Router(config-if)# ip address 10.10.1.2 255.255.255.0	Specifies the IP address for the Gigabit Ethernet interface.
Step 18	negotiation auto Example: Router(config-if)# negotiation auto	Enables the auto negotiation protocol to configure the speed, duplex, and automatic flow control of the Gigabit Ethernet interface.
Step 19	mpls ip Example: Router(config-if)# mpls ip	Enables MPLS forwarding of the IPv4 packets towards the MPLS core.
Step 20	exit	Exits the interface configuration mode.
Step 21	interface atm slot/subslot/port Example: Router(config)# interface atm 0/1/2	Configures an ATM interface and enters the interface configuration mode.
Step 22	no ip address Example: Router(config-if)# no ip address	Removes the previously configured IP address.
Step 23	atm clock internal Example: Router(config-if)# atm clock internal	Enables the ATM interface to generate the transmit clock internally.
Step 24	no atm enable-ilmi-trap Example: Router(config-if)# no atm enable-ilmi-trap	Disables the Integrated Local Management Interface (ILMI) ATM traps.
Step 25	exit	Exits the interface configuration mode.
Step 26	interface atm slot/subslot/port [.subinterface-number {point-to-point}] Example: Router(config)# interface atm 0/1/2.1 point-to-point	Configures an ATM interface and enters the interface configuration mode.
Step 27	mtu bytes Example: Router(config-subif)# mtu 1500	Adjusts the maximum packet size or maximum transmission unit (MTU) size. Note The MTU sizes of both the attachment circuits must match.
Step 28	no atm enable-ilmi-trap Example: Router(config-subif)# no atm enable-ilmi-trap	Disables the ILMI ATM traps.
Step 29	pvc [name] vpi/vci l2transport Example: Router(config-subif)# pvc cisco 10/100 l2transport	Assigns a name to an ATM PVC, specifies the encapsulation type on an ATM PVC, and enters the ATM virtual circuit configuration mode.
Step 30	encapsulation encapsulation-type Example: Router(config-if-atm-l2trans-pvc)# encapsulation aal5snap	Sets the AAL5SNAP encapsulation (Any-to-Any) for the ATM point-to-point interface.
Step 31	xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name Example: Router(config-if-atm-l2trans-pvc)# xconnect 190.1.1.1 100 encapsulation mpls pw-class atm-fr-bridged	Binds an attachment circuit to a pseudowire and configures an Any Transport over MPLS (AToM) static pseudowire.
Step 32	exit	Exits to the global configuration mode.

Example: Frame Relay-to-ATM Bridged Interworking on an ATM-PE Router

The following example shows the configuration of the Frame Relay-to-ATM Bridged Interworking feature on an ATM-PE router:

no ip domain lookup

mpls label range 101 4000 static 4001 5001

mpls label protocol ldp

mpls ip default-route

mpls ldp graceful-restart

xconnect logging pseudowire status

!

pseudowire-class atm-fr-bridged

encapsulation mpls

interworking ethernet

!

interface Loopback0

ip address 44.1.1.2 255.255.255.255

!

interface GigabitEthernet0/0/1

ip address 10.10.1.2 255.255.255.0

negotiation auto

mpls ip

!

interface ATM0/1/2

no ip address

atm clock INTERNAL

no atm enable-ilmi-trap

!

interface ATM0/1/2.1 point-to-point

mtu 1500

no atm enable-ilmi-trap

pvc 10/100 l2transport

encapsulation aal5snap

xconnect 190.1.1.1 100 pw-class atm-fr-bridged

!

!

To configure the Frame Relay-to-ATM Bridged Interworking feature on a Frame Relay PE router, perform the following steps:

---

Note The following configuration uses a channelized T1/E1 interface. Frame Relay can be configured on other interfaces such as Packet over SONET (PoS) as well.

---

SUMMARY STEPS

1. enable

2. configure terminal

3. (Optional) ipv6 unicast-routing

4. mpls label protocol ldp

5. mpls ip default-route

6. mpls ldp graceful-restart

7. frame-relay switching

8. xconnect logging pseudowire status

9. controller t1 slot/subslot/port

10. framing esf

11. clock source internal

12. linecode b8zs

13. cablelength long db-loss-value

14. channel-group channel-group-number timeslots range

15. exit

16. pseudowire-class [pw-class-name]

17. encapsulation mpls

18. interworking ethernet

19. exit

20. interface loopback loopback-interface-number

21. ip address ip-address mask

22. exit

23. interface serial slot/subslot/port:timeslot

24. no ip address

25. encapsulation frame-relay

26. frame-relay intf-type dce

27. frame-relay interface-dlci dlci switched

28. exit

29. interface GigabitEthernet slot/subslot/port

30. ip address ip-address mask

31. negotiation auto

32. mpls ip

33. exit

34. connect connection-name interface dlci l2transport

35. xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name

36. exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	ipv6 unicast-routing Example: Router# ipv6 unicast-routing	(Optional) Enables the task of forwarding the IPv6 unicast datagrams.
Step 4	mpls label protocol ldp Example: Router(config)# mpls label protocol ldp	Specifies the label distribution protocol (LDP) for the Frame Relay PE router.
Step 5	mpls ip default-route Example: Router(config)# mpls ip default-route	Enables the distribution of labels associated with the IP default route.
Step 6	mpls ldp graceful-restart Example: Router(config)# mpls ldp graceful-restart	Enables MPLS LDP graceful restart.
Step 7	frame-relay switching Example: Router(config)# frame-relay switching	Enables PVC switching on a Frame Relay data circuit-terminating equipment (DCE) device.
Step 8	xconnect logging pseudowire status Example: Router(config)# xconnect logging pseudowire status	Enables system logging (syslog) reporting of pseudowire status events.
Step 9	controller t1 slot/subslot/port Example: Router(config)# controller T1 0/3/0	Configures a T1 controller and enters the controller configuration mode.
Step 10	framing esf Example: Router(config-controller)# framing esf	Selects the Extended Super Frame (ESF) for a T1 data line.
Step 11	clock source internal Example: Router(config-controller)# clock source internal	Configures the clock source of a DS1 link and uses the internal clock from the interface.
Step 12	linecode b8zs Example: Router(config-controller)# linecode b8zs	Specifies Binary 8-Zero Substitution (B8ZS) as the line code type for the T1 controller.
Step 13	cablelength long db-loss-value Example: Router(config-controller)# cablelength long 0db	Decreases the transmit signal by 0 dB. This is the default value.
Step 14	channel-group channel-group-number timeslots range Example: Router(config-controller)# channel-group 0 timeslots 1-24	Configures serial WAN on a T1 or E1 interface.
Step 15	exit	Exits the pseudowire class configuration mode.
Step 16	pseudowire-class [pw-class-name] Example: Router(config)# pseudowire-class atm-fr-bridged	Establishes a pseudowire class with a name that you specify and enters the pseudowire class configuration mode.
Step 17	encapsulation mpls Example: Router(config-pw-class)# encapsulation mpls	Enables MPLS encapsulation on the interface.
Step 18	interworking ethernet Example: Router(config-pw-class)# interworking ethernet	Enables the L2VPN Ethernet interworking feature.
Step 19	exit	Exits the pseudowire class configuration mode.
Step 20	interface loopback loopback-interface-number Example: Router(config)# interface loopback 0	Specifies the Loopback logical interface.
Step 21	ip address ip-address mask Example: Router(config-if)# ip address 44.1.1.2 255.255.255.255	Specifies the IP address for the Loopback interface.
Step 22	exit	Exits the interface configuration mode.
Step 23	interface serial slot/subslot/port:timeslot Example: Router(config)# interface Serial0/3/0:0	Specifies a serial interface created on a channelized T1 controller.
Step 24	no ip address Example: Router(config-if)# no ip address	Removes the previously configured IP address.
Step 25	encapsulation frame-relay Example: Router(config-if)# encapsulation frame-relay	Configures the Cisco Frame Relay encapsulation on serial interface.
Step 26	frame-relay intf-type dce Example: Router(config-if)# frame-relay intf-type dce	Configures a Frame Relay switch type. The router functions as a switch connected to a router.
Step 27	frame-relay interface-dlci dlci switched Example: Router(config-if)# frame-relay interface-dlci 101 switched	Assigns a data-link connection identifier (DLCI) to a specified Frame Relay subinterface on the router.
Step 28	exit	Exits the interface configuration mode.
Step 29	interface GigabitEthernet slot/subslot/port Example: Router(config)# interface GigabitEthernet 0/0/1	Specifies the Gigabit Ethernet interface for the connection of the PE routers.
Step 30	ip address ip-address mask Example: Router(config-if)# ip address 10.10.1.2 255.255.255.0	Specifies the IP address for the Gigabit Ethernet interface.
Step 31	negotiation auto Example: Router(config-if)# negotiation auto	Enables the auto negotiation protocol to configure the speed, duplex, and automatic flow control of the Gigabit Ethernet interface.
Step 32	mpls ip Example: Router(config-if)# mpls ip	Enables MPLS forwarding of the IPv4 packets towards the MPLS core.
Step 33	exit	Exits the interface configuration mode.
Step 34	connect connection-name interface dlci l2transport Example: Router(config)# connect fr-atm-2 Serial0/3/0:0 101 l2transport	Defines connections between the Frame Relay PVCs.
Step 35	xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name Example: Router(config-conn)# xconnect 190.1.1.1 100 encapsulation mpls pw-class atm-fr-bridged	Binds an attachment circuit to a pseudowire and configures an AToM static pseudowire.
Step 36	exit	Exits the global configuration mode.

Example: Frame Relay-to-ATM Bridged Interworking on a Frame Relay-PE Router

The following example shows the configuration of the Frame Relay-to-ATM Bridged Interworking feature on a Frame Relay-PE router:

ipv6 unicast-routing

mpls label protocol ldp

mpls ip default-route

mpls ldp graceful-restart

frame-relay switching

xconnect logging pseudowire status

!

controller T1 0/3/0

framing esf

clock source internal

linecode b8zs

cablelength long 0db

channel-group 0 timeslots 1-24

!

pseudowire-class atm-fr-bridged

encapsulation mpls

interworking ethernet

!

interface Loopback0

ip address 190.1.1.1 255.255.255.255

!

interface Serial0/3/0:0

no ip address

encapsulation frame-relay

frame-relay intf-type dce

frame-relay interface-dlci 101 switched

!

interface GigabitEthernet1/3/1

ip address 10.10.1.1 255.255.255.0

negotiation auto

mpls ip

!

connect fr-atm-2 Serial0/3/0:0 101 l2transport

xconnect 44.1.1.2 100 pw-class atm-fr-bridged

!

Gigabit EtherChannel for Virtual Private Wire Service

GEC for AToM is a solution for a VPWS transporting Layer 2 packets over an MPLS backbone with GEC.

This feature enables service providers to supply connectivity between customer sites having data link layer (Layer 2) networks, by using a single, integrated, packet-based network infrastructure—a Cisco MPLS network. Instead of separate networks with separate network management environments, service providers can deliver Layer 2 connections over an MPLS backbone.

Supported Modes

The following modes are supported in the GEC for VPWS feature:

•GEC Like-to-Like Mode

•Any-to-GEC Mode

GEC Like-to-Like Mode

The GEC Like-to-Like mode allows switching of data between two physical interfaces in which the two segments (CE1-PE1 and CE2-PE2, as shown in Figure 5) are both of GEC type.

The GEC Like-to-Like mode has the following features:

•EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking

•EtherChannel-to-EtherChannel over MPLS (Routed) Interworking

Figure 5 Topology of the GEC Like-to-Like Mode for the GEC for VPWS Feature

Any-to-GEC Mode

The Any-to-GEC mode allows switching of data between two physical interfaces in which the two segments, CE1-PE1 and CE2-PE2, are both of different types, while one is GEC, the other can be PPP, Ethernet, Frame Relay, or ATM, as shown in Figure 6.

The Any-to-GEC mode has the following features:

•Any-to-EtherChannel over MPLS (Bridged) Interworking

•Any-to-EtherChannel over MPLS (Routed) Interworking

Figure 6 Topology of the Any-to-GEC Mode for the GEC for VPWS Feature

---

Note Bridged interworking is used when Layer 2 (L2) packets are considered without regard for Layer 3 contents. In bridged interworking, Ethernet frames that are extracted from the attachment circuit are sent over the MPLS pseudowire.

---

---

Note Routed interworking is used to carry Layer 3 packets. In routed interworking, IP packets that are extracted from the attachment circuits are sent over the MPLS pseudowire.

---

Restrictions for Gigabit EtherChannel for Virtual Private Wire Service

The following are the restrictions for Gigabit EtherChannel for VPWS are the followings:

•GEC for VPWS does not support Q-in-Q encapsulation and remote port shutdown.

•A maximum four member links are supported under the port channel and a maximum of 64 port channel bundles are supported per router.

Configuring Gigabit EtherChannel for Virtual Private Wire Service

The GEC VPWS support feature is supported by AToM on the EtherChannel Interface, and includes the following features:

•EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking

•EtherChannel-to-EtherChannel over MPLS (Routed) Interworking

•Any-to-EtherChannel over MPLS (Bridged) Interworking

•Any-to-EtherChannel over MPLS (Routed) Interworking

EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking

Configure L2VPN interworking on the upstream interfaces of the PE routers. For more information about configuring L2VPN interworking on the PE routers, see L2VPN Interworking Modes.

After configuring MPLS Forwarding, perform the following steps on the downstream interfaces of the PE routers.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls label protocol ldp

4. interface loopback loopback-interface-number

5. ip address ip-address ip-subnet-mask

6. exit

7. pseudowire-class pw-class-name

8. encapsulation mpls

9. interworking ethernet

10. exit

11. interface port-channel number

12. xconnect peer-ip-address vc-id encapsulation mpls pseudowire-class pw-class-name

13. interface GigabitEthernet slot | subslot | port

14. channel-group port-channel number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable	Changes the privilege level for the corresponding CLI session.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	mpls label protocol ldp Example: Router# mpls label protocol ldp	Specifies that LDP is the default label distribution protocol.
Step 4	interface loopback loopback-interface-number Example: Router# interface loopback 1	Specifies the loopback interface, and enters the interface configuration mode.
Step 5	ip address ip-address mask Example: Router# ip address 10.10.2.1 255.255.255.0	Sets the IP address and mask for the loopback interface.
Step 6	exit	Exits the interface configuration mode.
Step 7	pseudowire-class pw-class-name Example: Router(config)# pseudowire-class gec-bridged	Specifies the name of a Layer 2 pseudowire class and enters the pseudowire class configuration mode.
Step 8	encapsulation mpls Example: Router(config-pw)# encapsulation mpls	Uses MPLS as the tunneling method to encapsulate data in the pseudowire.
Step 9	interworking ethernet Example: Router(config-pw)# interworking ethernet	Enables the L2VPN Interworking feature, and causes Ethernet frames to be extracted from the attachment circuit and sent over the pseudowire. Ethernet end-to-end transmission is assumed. Attachment circuit frames that do not contain Ethernet frames are dropped. In the case of VLAN, the VLAN tag is removed, which leaves a pure Ethernet frame.
Step 10	exit	Exits the xconnect configuration mode.
Step 11	interface port-channel number Example: Router(config)# interface port-channel 1	Creates an EtherChannel interface on the Cisco Cable Modem Termination System (CMTS).
Step 12	xconnect peer-ip-address vc-id encapsulation mpls pseudowire-class pw-class-name Example: Router(config-if)# xconnect 10.0.0.1 707 encapsulation mpl pseudowire-class gec-bridged	Binds an attachment circuit to a pseudowire to configure an AToM static pseudowire, specifies MPLS as the tunneling method, and enters the xconnect configuration mode.
Step 13	interface GigabitEthernet slot | subslot | port Example: Router(config)# interface GigabitEthernet 0/0/1	Specifies the Gigabit Ethernet interface, and enters the interface configuration mode.
Step 14	channel-group port-channel number Example: Router(config-if) channel-group 1	Configures an EtherChannel interface to an EtherChannel group

---

Note The EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking mode is also supported under VLAN.

---

EtherChannel-to-EtherChannel over MPLS (Routed) Interworking

Configure L2VPN interworking on the upstream interfaces of the PE routers. For more information about configuring L2VPN interworking on the PE routers, see L2VPN Interworking Modes.

After configuring MPLS Forwarding, perform the following steps on the downstream interfaces of the PE routers.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls label protocol ldp

4. interface loopback loopback-interface-number

5. ip address ip-address ip-subnet-mask

6. exit

7. pseudowire-class pw-class-name

8. encapsulation mpls

9. interworking ip

10. exit

11. interface port-channel number

12. xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name

13. interface GigabitEthernet slot | subslot | port

14. channel-group port-channel number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable	Changes the privilege level for the corresponding CLI session.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	mpls label protocol ldp Example: Router# mpls label protocol ldp	Specifies that LDP is the default label distribution protocol.
Step 4	interface loopback loopback-interface-number Example: Router# interface loopback 1	Specifies the loopback interface, and enters the interface configuration mode.
Step 5	ip address ip-address mask Example: Router# ip address 10.10.2.1 255.255.255.0	Sets the IP address and mask for the loopback interface.
Step 6	exit	Exits the interface configuration mode.
Step 7	pseudowire-class pw-class-name Example: Router(config)# pseudowire-class gec-bridged	Specifies the name of a Layer 2 pseudowire class and enters the pseudowire class configuration mode.
Step 8	encapsulation mpls Example: Router(config-pw)# encapsulation mpls	Uses MPLS as the tunneling method to encapsulate data in the pseudowire.
Step 9	interworking ip Example: Router(config-pw)# interworking ip	Enables the L2VPN Interworking feature, and causes IP packets to be extracted from the attachment circuit and sent over the pseudowire. Attachment circuit frames that do not contain IPv4 packets are dropped.
Step 10	exit	Exits the xconnect configuration mode.
Step 11	interface port-channel number Example: Router(config)# interface port-channel 1	Creates an EtherChannel interface on the Cisco Cable Modem Termination System (CMTS).
Step 12	xconnect peer-ip-address vc-id encapsulation mpls pseudowire-class pw-class-name Example: Router(config-if)# xconnect 10.0.0.1 707 encapsulation mpl pseudowire-class gec-routed	Binds an attachment circuit to a pseudowire to configure an AToM static pseudowire, specifies MPLS as the tunneling method, and enters the xconnect configuration mode.
Step 13	interface GigabitEthernet slot | subslot | port Example: Router(config)# interface GigabitEthernet 0/0/1	Specifies the Gigabit Ethernet interface, and enters the interface configuration mode.
Step 14	channel-group port-channel number Example: Router(config-if) channel-group 1	Configures EtherChannel interfaces to an EtherChannel group.

---

Note The EtherChannel-to-EtherChannel over MPLS (Routed) Interworking mode is also supported under VLAN.

---

Example: GEC Like-to-Like (Routed) Interworking

The following example shows the configuration of the GEC Like-to-Like (Routed) Interworking feature:

no ip domain lookup

mpls label range 101 4000 static 4001 5001

mpls label protocol ldp

mpls ip default-route

mpls ldp graceful-restart

xconnect logging pseudowire status

!

pseudowire-class gec-bridged

encapsulation mpls

interworking ethernet!

pseudowire-class gec-routed

encapsulation mpls

interworking ip

!

interface Loopback0

ip address 44.1.1.2 255.255.255.255

!

interface GigabitEthernet0/0/1

ip address 10.10.1.2 255.255.255.0

negotiation auto

mpls ip

!

interface port-channel 1

xconnect 190.1.1.1 100 encapsulation mpls pw-class gec-bridged

!

interface GigabitEthernet0/0/3

channel-group 1

!

interface GigabitEthernet0/0/2

channel-group 1

!

router ospf 10

log-adjacency-changes

network 44.1.1.2 0.0.0.0 area 0

network 10.10.1.2 0.0.0.255 area 0

Any-to-EtherChannel over MPLS (Bridged) Interworking

You can configure Any-to-EtherChannel over MPLS (Bridged) interworking on the Cisco ASR 1000 Series Routers.

Any-to-EtherChannel over MPLS (Bridged) interworking supports the following modes:

•Frame Relay-to-EtherChannel

•ATM-to-EtherChannel

•Ethernet-to-EtherChannel

Irrespective of the mode used, in Any-to-EtherChannel over MPLS (Bridged) interworking, configure L2VPN interworking on the upstream interfaces of PE routers. For more information about configuring L2VPN interworking on the PE routers, see L2VPN Interworking Modes.

For information about how to configure Frame Relay or ATM on the downstream interfaces of a PE router, see the Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking. Meanwhile, perform the steps described in the EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking, on the downstream interfaces of the other PE router.

For the Ethernet-to-EtherChannel mode, perform the steps described in EtherChannel-to-EtherChannel over MPLS (Bridged) Interworking on the downstream interfaces of the other PE router. Meanwhile, perform the following steps on the downstream interfaces of the PE routers.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls label protocol ldp

4. interface loopback loopback-interface-number

5. ip address ip-address ip-subnet-mask

6. exit

7. pseudowire-class pw-class-name

8. encapsulation mpls

9. interworking ethernet

10. interface GigabitEthernet slot | subslot | port

11. xconnect peer-ip-address vc-id encapsulation mpls pw-class pw-class-name

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable	Changes the privilege level for the corresponding CLI session.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	mpls label protocol ldp Example: Router# mpls label protocol ldp	Specifies that LDP is the default label distribution protocol.
Step 4	interface loopback loopback-interface-number Example: Router# interface loopback 1	Specifies the loopback interface, and enters the interface configuration mode.
Step 5	ip address ip-address mask Example: Router# ip address 10.10.2.1 255.255.255.0	Sets the IP address and mask for the loopback interface.
Step 6	exit	Exits the interface configuration mode.
Step 7	pseudowire-class pw-class-name Example: Router(config)# pseudowire-class gec-bridged	Specifies the name of a Layer 2 pseudowire class and enters the pseudowire class configuration mode.
Step 8	encapsulation mpls Example: Router(config-pw)# encapsulation mpls	Uses MPLS as the tunneling method to encapsulate data in the pseudowire.
Step 9	interworking ethernet Example: Router(config-pw)# interworking ethernet	Enables the L2VPN Interworking feature, and causes Ethernet frames to be extracted from the attachment circuit and sent over the pseudowire. Ethernet end-to-end transmission is assumed. Attachment circuit frames that do not contain Ethernet frames are dropped. In the case of VLAN, the VLAN tag is removed, which leaves a pure Ethernet frame.
Step 10	interface GigabitEthernet slot | subslot | port Example: Router(config)# interface GigabitEthernet 0/0/1	Specifies the Gigabit Ethernet interface, and enters the interface configuration mode.
Step 11	xconnect peer-ip-address vc-id encapsulation mpls pseudowire-class pw-class-name Example: Router(config-if)# xconnect 10.0.0.1 707 encapsulation mpl pseudowire-class gec-bridged	Binds an attachment circuit to a pseudowire to configure an AToM static pseudowire, specifies MPLS as the tunneling method, and enters the xconnect configuration mode.

---

Note Ethernet-to-EtherChannel over MPLS (Bridge) Interworking mode is also supported under VLAN.

---

Any-to-EtherChannel over MPLS (Routed) Interworking

You can configure Any-to-EtherChannel over MPLS (Routed) interworking on the Cisco ASR 1000 Series Routers.

Any-to-EtherChannel over MPLS (Routed) interworking supports the following modes:

•ATM-to-EtherChannel

•Ethernet-to-EtherChannel

•PPP-to-EtherChannel

Configure L2VPN interworking on the upstream interfaces of PE routers. For more information about configuring L2VPN interworking on the PE routers, see L2VPN Interworking Modes.

For information about how to configure ATM on the downstream interfaces of a PE router, see the Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking. Meanwhile, perform the steps described in the EtherChannel-to-EtherChannel over MPLS (Routed) Interworking, on the downstream interfaces of the other PE router.

For the Ethernet-to-EtherChannel mode, see the Any-to-EtherChannel over MPLS (Bridged) Interworking.

For the PPP-to-EtherChannel mode, perform the steps described in the EtherChannel-to-EtherChannel over MPLS (Routed) Interworking, on the downstream interfaces of the other PE router. Meanwhile, perform the following steps on the downstream interfaces of the PE routers.

SUMMARY STEPS

1. enable

2. configure terminal

3. (Optional) ipv6 unicast-routing

4. mpls ip default-route

5. mpls ldp graceful-restart

6. xconnect logging pseudowire status

7. controller t1 slot | subslot | port

8. clock source internal

9. linecode b8zs

10. cablelength long db-loss-value

11. channel-group channel-group-number timeslots range

12. exit

13. pseudowire-class pw-class-name

14. encapsulation mpls

15. interworking ethernet

16. exit

17. interface loopback loopback-interface-number

18. ip address ip-address mask

19. exit

20. interface serial slot | subslot | port:timeslot

21. no ip address

22. encapsulation ppp

23. clock source internal

24. xconnect vc-id pw-class pw-class pw-class-name

25. xconnect peer-loopback vc-id pw-class pe-class-name

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables the privileged EXEC mode. Enter your password, if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters the global configuration mode.
Step 3	ipv6 unicast-routing Example: Router# ipv6 unicast-routing	(Optional) Enables the task of forwarding the IPv6 unicast datagrams.
Step 4	mpls ip default-route Example: Router(config)# mpls ip default-route	Enables the distribution of labels associated with the IP default route.
Step 5	mpls ldp graceful-restart Example: Router(config)# mpls ldp graceful-restart	Enables MPLS LDP graceful restart.
Step 6	xconnect logging pseudowire status Example: Router(config)# xconnect logging pseudowire status	Enables system logging (syslog) reporting of pseudowire status events.
Step 7	controller t1 slot/subslot/port Example: Router(config)# controller T1 0/3/0	Configures a T1 controller and enters the controller configuration mode.
Step 8	clock source internal Example: Router(config-controller)# clock source internal	Configures the clock source of a DS1 link and uses the internal clock from the interface.
Step 9	linecode b8zs Example: Router(config-controller)# linecode b8zs	Specifies Binary 8-Zero Substitution (B8ZS) as the line code type for the T1 controller.
Step 10	cablelength long db-loss-value Example: Router(config-controller)# cablelength long 0db	Decreases the transmit signal by 0 dB. This is the default value.
Step 11	channel-group channel-group-number timeslots range Example: Router(config-controller)# channel-group 0 timeslots 1-24	Configures serial WAN on a T1 or E1 interface.
Step 12	exit	Exits the pseudowire class configuration mode.
Step 13	pseudowire-class [pw-class-name] Example: Router(config)# pseudowire-class atm-fr-bridged	Establishes a pseudowire class with a name that you specify and enters the pseudowire class configuration mode.
Step 14	encapsulation mpls Example: Router(config-pw-class)# encapsulation mpls	Enables MPLS encapsulation on the interface.
Step 15	interworking ethernet Example: Router(config-pw-class)# interworking ethernet	Enables the L2VPN Ethernet interworking feature.
Step 16	exit	Exits the pseudowire class configuration mode.
Step 17	interface loopback loopback-interface-number Example: Router(config)# interface loopback 0	Specifies the Loopback logical interface.
Step 18	ip address ip-address mask Example: Router(config-if)# ip address 44.1.1.2 255.255.255.255	Specifies the IP address for the Loopback interface.
Step 19	exit	Exits the interface configuration mode.
Step 20	interface serial slot/subslot/port:timeslot Example: Router(config)# interface Serial0/3/0:0	Specifies a serial interface created on a channelized T1 controller.
Step 21	no ip address Example: Router(config-if)# no ip address	Removes the previously configured IP address.
Step 22	encapsulation ppp Example: Router(config-if)# encapsulation frame-relay	Configures the PPP (for serial interface) encapsulation on serial interface.
Step 23	clock source internal	Specifies that the T1/E1 link uses the internal clock from the interface.
Step 24	xconnect peer-loopback vc-id pw-class pe-class-name	Binds an attachment circuit to a pseudowire to configure an AToM static pseudowire, specifies MPLS as the tunneling method, and enters the xconnect configuration mode.

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Note Ethernet-to-EtherChannel over MPLS (Bridge) Interworking mode is also supported under VLAN.

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Additional References

The following sections provide references related to the Frame Relay to ATM Bridged Interworking and xconnect support on GEC (VPWS) features.

Related Documents

Related Topic	Document Title
Cisco IOS commands	Cisco IOS Master Commands List, All Releases
Basics of MPLS	MPLS: Basic MPLS Configuration Guide, Cisco IOS XE Release 3S
MPLS Layer 2 VPNs	MPLS Layer 2 VPNs Configuration Guide, Cisco IOS XE Release 3S
Cisco IOS Configuration Fundamentals	Cisco IOS Configuration Fundamentals Command Reference

Standards

Standard	Title
No new or modified standards are supported by this feature.	—

MIBs

MIB	MIBs Link
•CISCO-IETF-PW-MIB •CISCO-IETF-PW-MPLS-MIB	To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use the Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs

RFCs

RFC1	Title
RFC 2684	Multiprotocol Encapsulation over ATM Adaptation Layer 5
RFC 2427	Multiprotocol Interconnect over Frame Relay

1 Not all the supported RFCs are listed.

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

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

Feature Information for Configuring MPLS Layer 2 VPNs

Table 2 lists the features in this module and provides links to specific configuration information. Only features that were introduced or modified in Cisco IOS Release 3.6.0S or a later release appear in the table.

Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the corresponding command reference documentation.

Use the Cisco Feature Navigator to find information about platform support and software image support. The Cisco Feature Navigator enables you to determine which Cisco IOS and Cisco Catalyst operating system software images support a specific software release, feature set, or platform. To access the Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Table 2 Feature Information for Configuring MPLS Layer 2 VPNs

Feature Name	Releases	Feature Information
Frame Relay to ATM Bridged Interworking	3.6.0S	The Frame Relay to ATM Bridged Interworking feature provides interoperability between the Frame Relay attachment VC and the ATM attachment VC connected to different PE routers. The bridged encapsulation corresponding to the bridged (Ethernet) interworking mechanism is used. The Ethernet frames are carried through the MPLS network using Ethernet over MPLS (EoMPLS). In Cisco IOS XE Release 3.6.0S, this feature was implemented on the ASR 1000 Series Aggregation Services Routers. The following sections provide information about this feature: •Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking •Configuring Frame Relay DLCI-to-ATM AAL5SNAP Bridged Interworking
xconnect support on GEC (VPWS) on ASR1000	3.6.0S	The Xconnect Support on GEC (VPWS) on ASR1000 feature enables the service providers to supply connectivity between customer sites with existing data link layer (Layer 2) networks by using a single, integrated, packet-based network infrastructure—a Cisco MPLS network. Instead of separate networks with network management environments, service providers can deliver Layer 2 connections over an MPLS backbone. In Cisco IOS XE Release 3.6.0S, this feature was implemented on the ASR 1000 Series Aggregation Services Routers. The following sections provide information about this feature: •Gigabit EtherChannel for Virtual Private Wire Service •Configuring Gigabit EtherChannel for Virtual Private Wire Service
Reverse Layer 2 Gateway Protocol	3.8.0S	Reverse L2GP (R-L2GP) is a variation of L2GP. In case of R-L2GP, the pseudo information of the R-L2GP is transmitted by nPEs, instead of uPEs. R-L2GP provides a mechanism to send out static preconfigured BPDUs on each ring access port of nPEs to stimulate a per-access ring instantiation of the protocol. R-L2GP enables the PEs to avoid the burden of running Multiple-instance Spanning Tree Protocol (MST) when multiple independent access networks that run MST connect to a pair of redundant PEs. In order for this to work, the pair of nPEs are programmed to send out BPDUs on the access ring ports in such a way that they appear to be either: •The root bridge itself (the bridge with the lowest bridge id/priority). •The bridge with the second lowest bridge ID/priority, and with a 0 cost path to the root. The following sections provide information about this feature: •Reverse Layer 2 Gateway Protocol •Configuring the R-L2GP

Glossary

ATM—Asynchronous Transfer Mode. A method of data transportation, whereby fixed-length packets are sent over a switched network. The method's ability to ensure reliable delivery of packets at a high rate makes it suitable for carrying voice, video, and data.

AToM—Any Transport over MPLS. AToM is a solution for transporting Layer 2 packets over an MPLS backbone. AToM enables service providers to supply connectivity between customer sites with existing data link layer (Layer 2) networks by using a single, integrated, packet-based network infrastructure—a Cisco MPLS network. Instead of separate networks with separate network management environments, service providers can deliver Layer 2 connections over an MPLS backbone.

EoMPLS—Ethernet over MPLS. This technology leverages an existing MPLS backbone network to deliver Transparent LAN Services based on Ethernet connectivity to the customer site.

GEC—Gigabit EtherChannel. A high-performance Ethernet technology that provides gigabit per second transmission rates. It provides a flexible and scalable bandwidth with resiliency and load sharing across links for switches, router interfaces, and servers. Supports up to eight links per channel.

MPLS—Multiprotocol Label Switching. A mechanism in high-performance telecommunications networks that directs and carries data from one network node to the next. MPLS makes it easy to create virtual links between distant nodes. It can encapsulate packets of various network protocols.

VPLS—Virtual Private LAN Service. A method to provide Ethernet-based multipoint-to-multipoint communication over IP and MPLS networks.

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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

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