MPLS Layer 3 VPNs: Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.2SX

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.

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 MPLS VPN CSC with LDP and IGP

The provider edge (PE) routers of the backbone carrier require 128 MB of memory.
The backbone carrier must enable the PE router to check that the packets it receives from the customer edge (CE) router contain only the labels that the PE router advertised to the CE router. This prevents data spoofing, which occurs when a packet from an unrecognized IP address is sent to a router.

Restrictions for MPLS VPN CSC with LDP and IGP

The following features are not supported with this feature:

ATM MPLS
Carrier supporting carrier traffic engineering
Carrier supporting carrier quality of service (QoS)
RSVP aggregation
VPN Multicast between the customer carrier and the backbone carrier network

The following router platforms are supported on the edge of the MPLS VPN:

Cisco 7200 series
Cisco 7500 series
Cisco 12000 series

See the table below for Cisco 12000 series line card support added for Cisco IOS releases.

Table 1

Cisco12000 Series Line Card Support Added for Cisco IOS Releases

Type	Line Cards	Cisco IOS Release Added
Packet over SONET (POS)	4-Port OC-3 POS 1-Port OC-12 POS 8-Port OC-3 POS 16-Port OC-3 POS 4-Port OC-12 POS 1-Port OC-48 POS 4-Port OC-3 POS ISE 8-Port OC-3 POS ISE 16 x OC-3 POS ISE 4 Port OC-12 POS ISE 1-Port OC-48 POS ISE	12.0(16)ST 12.0(21)ST 12.0(22)S
Electrical Interface	6- Port DS3 12- Port DS3 6-Port E3	12.0(16)ST 12.0(21)ST
ATM	4-Port OC-3 ATM 1-Port OC12 ATM 4-Port OC-12 ATM	12.0(22)S
Channelized Interface	2-Port CHOC-3 6-Port Ch T3 (DS1) 1-Port CHOC-12 (DS3) 1-Port CHOC-12 (OC-3) 4-Port CHOC-12 ISE 1-Port CHOC-48 ISE	12.0(22)S

Information About MPLS VPN CSC with LDP and IGP

MPLS VPN CSC Introduction
Benefits of Implementing MPLS VPN CSC
Configuration Options for MPLS VPN CSC with LDP and IGP
Customer Carrier Is a BGP MPLS VPN Service Provider

MPLS VPN CSC Introduction

Carrier supporting carrier is where one service provider allows another service provider to use a segment of its backbone network. The service provider that provides the segment of the backbone network to the other provider is called the backbone carrier. The service provider that uses the segment of the backbone network is called the customer carrier.

A backbone carrier offers Border Gateway Protocol and Multiprotocol Label Switching (BGP/MPLS) VPN services. The customer carrier can be either:

An Internet service provider (ISP)
A BGP/MPLS VPN service provider

Benefits of Implementing MPLS VPN CSC

The MPLS VPN CSC network provides the following benefits to service providers who are backbone carriers and to customer carriers.

Benefits to the Backbone Carrier

The backbone carrier can accommodate many customer carriers and give them access to its backbone. The backbone carrier does not need to create and maintain separate backbones for its customer carriers. Using one backbone network to support multiple customer carriers simplifies the backbone carrier's VPN operations. The backbone carrier uses a consistent method for managing and maintaining the backbone network. This is also cheaper and more efficient than maintaining separate backbones.
The MPLS VPN carrier supporting carrier feature is scalable. Carrier supporting carrier can change the VPN to meet changing bandwidth and connectivity needs. The feature can accommodate unplanned growth and changes. The carrier supporting carrier feature enables tens of thousands of VPNs to be set up over the same network, and it allows a service provider to offer both VPN and Internet services.
The MPLS VPN carrier supporting carrier feature is a flexible solution. The backbone carrier can accommodate many types of customer carriers. The backbone carrier can accept customer carriers who are ISPs or VPN service providers or both. The backbone carrier can accommodate customer carriers that require security and various bandwidths.

Benefits to the Customer Carriers

The MPLS VPN carrier supporting carrier feature removes from the customer carrier the burden of configuring, operating, and maintaining its own backbone. The customer carrier uses the backbone network of a backbone carrier, but the backbone carrier is responsible for network maintenance and operation.
Customer carriers who use the VPN services provided by the backbone carrier receive the same level of security that Frame Relay or ATM-based VPNs provide. Customer carriers can also use IPSec in their VPNs for a higher level of security; it is completely transparent to the backbone carrier.
Customer carriers can use any link layer technology (SONET, DSL, Frame Relay, and so on) to connect the CE routers to the PE routers and the PE routers to the P routers. The MPLS VPN carrier supporting carrier feature is link layer independent. The CE routers and PE routers use IP to communicate, and the backbone carrier uses MPLS.
The customer carrier can use any addressing scheme and still be supported by a backbone carrier. The customer address space and routing information are independent of the address space and routing information of other customer carriers or the backbone provider.

Configuration Options for MPLS VPN CSC with LDP and IGP

The backbone carrier offers BGP and MPLS VPN services. The customer carrier can be one of the two types of service providers described in the following sections, which explain how the backbone and customer carriers distribute IPv4 routes and MPLS labels.

Customer Carrier Is an ISP

Customer Carrier Is an ISP

This section explains how a BGP/MPLS VPN service provider (backbone carrier) can provide a segment of its backbone network to a customer who is an ISP.

Consider the following example:

An ISP has two sites: one in California, the other in Maine. Each site is a point of presence (POP). The ISP wants to connect these sites using a VPN service provided by a backbone carrier. The figure below illustrates this situation.

Figure 1

Sample BGP/MPLS Backbone Carrier Supporting an ISP

Note

The CE routers in the figures are CE routers to the backbone carrier. However, they are PE routers to the customer carrier.

In this example, only the backbone carrier uses MPLS. The customer carrier (ISP) uses only IP. As a result, the backbone carrier must carry all the Internet routes of the customer carrier, which could be as many as 100,000 routes. This poses a scalability problem for the backbone carrier. To solve the scalability problem, the backbone carrier is configured as follows:

The backbone carrier allows only internal routes of the customer carrier (IGP routes) to be exchanged between the CE routers of the customer carrier and the PE routers of the backbone carrier.
MPLS is enabled on the interface between the CE router of the customer carrier and the PE router of the backbone carrier.

Internal and external routes are differentiated this way:

Internal routes go to any of the routers within the ISP.
External routes go to the Internet.

The number of internal routes is much lower than the number of external routes. Restricting the routes between the CE routers of the customer carrier and the PE routers of the backbone carrier significantly reduces the number of routes that the PE router needs to maintain.

Because the PE routers do not have to carry external routes in the VRF routing table, they can use the incoming label in the packet to forward the customer carrier Internet traffic. Adding MPLS to the routers provides a consistent method of transporting packets from the customer carrier to the backbone carrier. MPLS allows the exchange of an MPLS label between the PE and the CE routers for every internal customer carrier route. The routers in the customer carrier have all the external routes either through internal Border Gateway Protocol (iBGP) or route redistribution to provide Internet connectivity. The figure below shows how information is exchanged when the network is configured in this manner.

Figure 2

Backbone Carrier Exchanging Routing Information with a Customer Carrier Who Is an ISP

In the figure below, routes are created between the backbone carrier and the customer carrier sites. ASBR2 receives an Internet route that originated outside the network. All routers in the ISP sites have all the external routes through IBGP connections among them.

Figure 3

Establishing a Route Between a Backbone Carrier and a Customer Carrier Who Is an ISP

The table below describes the process of establishing the route, which can be divided into two distinct steps:

The backbone carrier propagates the IGP information of the customer carrier, which enables the customer carrier routers to reach all the customer carrier routers in the remote sites.
Once the routers of the customer carriers in different sites are reachable, external routes can be propagated in the customer carrier sites, using IBGP without using the backbone carrier routers.

Table 2

Establishing a Route Between the Backbone Carrier and the Customer Carrier ISP

Step	Description
1	CSC-CE2 sends the internal routes within site 2 to CSC-PE2. The routes include the route to ASBR2.
2	CSC-PE2 sends the routing information for site 2 to CSC-PE1, using MPLS VPN processes. CSC-PE1 gets one label (called L3), which is associated with the route to the VPN-IP address for ASBR2. CSC-PE1 gets another label (called L2), which is associated with the route to CSC-PE2.
3	CSC-PE1 sends the routing information associated with internal routes from site 2 to CSC-CE1. CSC-PE1 also sends the label binding information. As a result, CSC-CE1 gets the route to ASBR2 with CSC-PE1 as the next hop. The label associated with that route is called L1.
4	CSC-CE1 distributes the routing information through site 1. Every router in site 1 gets a route for every internal destination in site 2. Therefore, every router in site 1 can reach routers in site 2 and learn external routes through IBGP.
5	ASBR2 receives an Internet route.
6	The IBGP sessions exchange the external routing information of the ISP, including a route to the Internet. Every router in site 1 knows a route to the Internet, with ASBR2 as the next hop of that route.

Customer Carrier Is a BGP MPLS VPN Service Provider

When a backbone carrier and the customer carrier both provide BGP/MPLS VPN services, the method of transporting data is different from when a customer carrier provides only ISP services. The following list highlights those differences:

When a customer carrier provides BGP/MPLS VPN services, its external routes are VPN-IPv4 routes. When a customer carrier is an ISP, its external routes are IP routes.
When a customer carrier provides BGP/MPLS VPN services, every site within the customer carrier must use MPLS. When a customer carrier is an ISP, the sites do not need to use MPLS.

The figure below shows how information is exchanged when MPLS VPN services reside on all customer carrier sites and on the backbone carrier.

Figure 4

Backbone Carrier Exchanging Information with a Customer Carrier Who Is an MPLS VPN Service Provider

In the example shown in the figure below, routes are created between the backbone carrier and the customer carrier sites.

Figure 5

Establishing a Route Between a Backbone Carrier and a Customer Carrier Who Is an MPLS VPN Service Provider

The table below describes the process of establishing the route.

Table 3

Establishing a Route Between the Backbone Carrier and Customer Carrier Site

Step	Description
1	CE2 sends all the internal routes within site 2 to CSC-PE2.
2	CSC-PE2 sends the routing information for site 2 to CSC-PE1, using MPLS VPN processes. CSC-PE1 gets one label (called L3), which is associated with the route to the VPN-IP address for PE2. CSC-PE1 gets another label (called L2), which is associated with the route to CSC-PE2.
3	CSC-PE1 sends the routing information associated with internal routes from site 2 to CSC-CE1. CSC-PE1 also sends the label binding information. As a result, CSC-CE1 gets the route to PE2 with CSC-PE1 as the next hop. The label associated with that route is called L1.
4	CE1 distributes the routing and labeling information through site 1. Every router in site 1 gets a route for every internal destination in site 2. Therefore, PE1 can establish an MP-IBGP session with PE2.
5	CE2 advertises the internal routes of MPLS VPN site 2 to PE2.
6	PE2 allocates labels for all the VPN routes (regular MPLS VPN functionality) and advertises the labels to PE1, using MP-IBGP.
7	PE1 can forward traffic from VPN site 1 that is destined for VPN site 2.

How to Configure MPLS VPN CSC with LDP and IGP

Configuring the Backbone Carrier Core
Configuring the CSC-PE and CSC-CE Routers
Verifying the Carrier Supporting Carrier Configuration

Configuring the Backbone Carrier Core

Configuring the backbone carrier core requires configuring connectivity and routing functions for the CSC core and the CSC-PE routers.

Configuring and verifying the CSC core (backbone carrier) involves the following tasks:

Prerequisites
Verifying IP Connectivity and LDP Configuration in the CSC Core
Configuring VRFs for CSC-PE Routers
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier

Prerequisites

Before you configure a backbone carrier core, configure the following on the CSC core routers:

An IGP routing protocol--BGP, OSPF, IS-IS, EIGRP, static, and so on. For information, see Configuring a Basic BGP Network, Configuring OSPF, Configuring a Basic IS-IS Network, and Configuring EIGRP.
Label Distribution Protocol (LDP). For information, see MPLS Label Distribution Protocol.

Verifying IP Connectivity and LDP Configuration in the CSC Core

Perform this task to verify IP connectivity and LDP configuration in the CSC core. For a configuration example for this task, see the Verifying IP Connectivity and LDP Configuration in the CSC Core.

SUMMARY STEPS

1. enable

2. ping [protocol] {host-name | system-address}

3. trace [protocol] [destination]

4. show mpls forwarding-table [network {mask | length} | labels label [-label] | interface interface | next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]

5. show mpls ldp discovery [vrf vrf-name | all]

6. show mpls ldp neighbor [[vrf vrf-name] [address | interface] [detail] | all]

7. show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail]

8. show mpls interfaces [[vrf vrf-name] [interface] [detail] |all]

9. show ip route

10. disable

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	ping [protocol] {host-name \| system-address} Example: Router# ping ip 10.0.0.1	(Optional) Diagnoses basic network connectivity on AppleTalk, Connectionless Network Service (CLNS), IP, Novell, Apollo, VINES, DECnet, or Xerox Network System (XNS) networks. Use the ping ip command to verify the connectivity from one CSC core router to another.
Step 3	trace [protocol] [destination] Example: Router# trace ip 10.0.0.1	(Optional) Discovers the routes that packets will actually take when traveling to their destination. Use the trace command to verify the path that a packet goes through before reaching the final destination. The trace command can help isolate a trouble spot if two routers cannot communicate.
Step 4	show mpls forwarding-table [network {mask \| length} \| labels label [-label] \| interface interface \| next-hop address \| lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail] Example: Router# show mpls forwarding-table	(Optional) Displays the contents of the MPLS label forwarding information base (LFIB). Use the show mpls forwarding-table command to verify that MPLS packets are being forwarded.
Step 5	show mpls ldp discovery [vrf vrf-name \| all] Example: Router# show mpls ldp discovery	(Optional) Displays the status of the LDP discovery process. Use the show mpls ldp discovery command to verify that LDP is operational in the CSC core.
Step 6	show mpls ldp neighbor [[vrf vrf-name] [address \| interface] [detail] \| all] Example: Router# show mpls ldp neighbor	(Optional) Displays the status of LDP sessions. Use theshow mpls ldp neighbor command to verify LDP configuration in the CSC core.
Step 7	show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail] Example: Router# show ip cef	(Optional) Displays entries in the forwarding Information Base (FIB). Use the show ip cef command to check the forwarding table (prefixes, next hops, and interfaces).
Step 8	show mpls interfaces [[vrf vrf-name] [interface] [detail] \|all] Example: Router# show mpls interfaces	(Optional) Displays information about one or more or all interfaces that are configured for label switching. Use theshow mpls interfaces command to verify that the interfaces are configured to use LDP.
Step 9	show ip route Example: Router# show ip route	(Optional) Displays IP routing table entries. Use the show ip route command to display the entire routing table, including host IP address, next hop, and interface.
Step 10	disable Example: Router# disable	(Optional) Returns to privileged EXEC mode.

Troubleshooting Tips

Troubleshooting Tips

You can use the ping and trace commands to verify complete MPLS connectivity in the core. You also get useful troubleshooting information from the additional show commands.

Configuring VRFs for CSC-PE Routers

Perform this task to configure VPN routing and forwarding (VRF) instances for the backbone carrier edge (CSC-PE) routers.

SUMMARY STEPS

1. enable

2. configure terminal

3. ip vrf vrf-name

4. rd route-distinguisher

5. route-target {import | export | both} route-target-ext-community

6. import map route-map

7. exit

8. interface type number

9. ip vrf forwarding vrf-name

10. end

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	ip vrf vrf-name Example: Router(config)# ip vrf vpn1	Defines the VPN routing instance by assigning a VRF name and enters VRF configuration mode. The vrf-name argument is the name assigned to a VRF.
Step 4	rd route-distinguisher Example: Router(config-vrf)# rd 100:1	Creates routing and forwarding tables. The route-distinguisher argument adds an 8-byte value to an IPv4 prefix to create a VPN-IPv4 prefix. You can enter an RD in either of these formats: 16-bit AS number: your 32-bit number, for example, 101:3 32-bit IP address: your 16-bit number, for example, 192.168.122.15:1
Step 5	route-target {import \| export \| both} route-target-ext-community Example: Router(config-vrf)# route-target import 100:1	Creates a route-target extended community for a VRF. The import keyword imports routing information from the target VPN extended community. The export keyword exports routing information to the target VPN extended community. The both keyword imports routing information from and exports routing information to the target VPN extended community. The route-target-ext-community argument adds the route-target extended community attributes to the VRF's list of import, export, or both (import and export) route-target extended communities.
Step 6	import map route-map Example: Router(config-vrf)# import map vpn1-route-map	(Optional) Configures an import route map for a VRF. The route-map argument specifies the route map to be used as an import route map for the VRF.
Step 7	exit Example: Router(config-vrf)# exit	(Optional) Exits to global configuration mode.
Step 8	interface type number Example: Router(config)# interface Ethernet5/0	Specifies the interface to configure and enters interface configuration mode. The type argument specifies the type of interface to be configured. The number argument specifies the port, connector, or interface card number.
Step 9	ip vrf forwarding vrf-name Example: Router(config-if)# ip vrf forwarding vpn1	Associates a VRF with the specified interface or subinterface. The vrf-name argument is the name assigned to a VRF.
Step 10	end Example: Router(config-if)# end	(Optional) Exits to privileged EXEC mode.

Troubleshooting Tips

Troubleshooting Tips

Enter a show ip vrf detail command and make sure the MPLS VPN is up and associated with the right interfaces.

Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier

Perform this task to configure Multiprotocol BGP (MP-BGP) connectivity in the backbone carrier.

SUMMARY STEPS

1. enable

2. configure terminal

3. router bgp as-number

4. no bgp default ipv4-unicast

5. neighbor {ip-address | peer-group-name} remote-as as-number

6. neighbor {ip-address | peer-group-name} update-source interface-type

7. address-family vpnv4 [unicast]

8. neighbor {ip-address | peer-group-name} send-community extended

9. neighbor {ip-address | peer-group-name} activate

10. end

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	router bgp as-number Example: Router(config)# router bgp 100	Configures a BGP routing process and enters router configuration mode. The as-number argument indicates the number of an autonomous system that identifies the router to other BGP routers and tags the routing information passed along. Valid numbers are from 0 to 65535. Private autonomous system numbers that can be used in internal networks range from 64512 to 65535.
Step 4	no bgp default ipv4-unicast Example: Router(config-router)# no bgp default ipv4-unicast	(Optional) Disables the IPv4 unicast address family on all neighbors. Use the no bgp default-unicast command if you are using this neighbor for MPLS routes only.
Step 5	neighbor {ip-address \| peer-group-name} remote-as as-number Example: Router(config-router)# neighbor 10.5.5.5 remote-as 100	Adds an entry to the BGP or multiprotocol BGP neighbor table. The ip-address argument specifies the IP address of the neighbor. The peer-group-name argument specifies the name of a BGP peer group. The as-number argument specifies the autonomous system to which the neighbor belongs.
Step 6	neighbor {ip-address \| peer-group-name} update-source interface-type Example: Router(config-router)# neighbor 10.2.0.0 update-source loopback0	Allows BGP sessions to use a specific operational interface for TCP connections. The ip-address argument specifies the IP address of the BGP-speaking neighbor. The peer-group-name argument specifies the name of a BGP peer group. The interface-type argument specifies the interface to be used as the source.
Step 7	address-family vpnv4 [unicast] Example: Router(config-router)# address-family vpnv4	Enters address family configuration mode for configuring routing sessions, such as BGP, that use standard VPNv4 address prefixes. The optional unicast keyword specifies VPNv4 unicast address prefixes.
Step 8	neighbor {ip-address \| peer-group-name} send-community extended Example: Router(config-router-af)# neighbor 10.0.0.1 send-community extended	Specifies that a communities attribute should be sent to a BGP neighbor. The ip-address argument specifies the IP address of the BGP-speaking neighbor. The peer-group-name argument specifies the name of a BGP peer group.
Step 9	neighbor {ip-address \| peer-group-name} activate Example: Router(config-router-af)# neighbor 10.4.0.0 activate	Enables the exchange of information with a neighboring BGP router. The ip-address argument specifies the IP address of the neighbor. The peer-group-name argument specifies the name of a BGP peer group.
Step 10	end Example: Router(config-router-af)# end	(Optional) Exits to privileged EXEC mode.

Troubleshooting Tips
Troubleshooting Tips

Troubleshooting Tips

You can enter a show ip bgp neighbor command to verify that the neighbors are up and running. If this command generates an error message, enter a debug ip bgp x.x.x.x events command, where x.x.x.x is the IP address of the neighbor.

Configuring the CSC-PE and CSC-CE Routers

To enable the CSC-PE and CSC-CE routers to distribute routes and MPLS labels, perform the following tasks:

Prerequisites
Configuring LDP on the CSC-PE and CSC-CE Routers
Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers

Prerequisites

Before you configure the CSC-PE and CSC-CE routers, you must configure an IGP on the CSC-PE and CSC-CE routers. A routing protocol is required between the PE and CE routers that connect the backbone carrier to the customer carrier. The routing protocol enables the customer carrier to exchange IGP routing information with the backbone carrier. Use the same routing protocol that the customer carrier uses. You can choose RIP, OSPF, or static routing as the routing protocol. BGP is not supported. For the configuration steps, see Configuring MPLS Layer 3 VPNs .

Configuring LDP on the CSC-PE and CSC-CE Routers

MPLS LDP is required between the PE and CE routers that connect the backbone carrier to the customer carrier. You can configure LDP as the default label distribution protocol for the entire router or just for the PE-to-CE interface for VRF.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls label protocol ldp

4. interface type number

5. mpls label protocol ldp

6. exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	mpls label protocol ldp Example: Router(config)# mpls label protocol ldp	Specifies MPLS LDP as the default label distribution protocol for the router.
Step 4	interface type number Example: Router(config)# interface Ethernet5/0	(Optional) Specifies the interface to configure and enters interface configuration mode. The type argument specifies the type of interface to be configured. The number argument specifies the port, connector, or interface card number.
Step 5	mpls label protocol ldp Example: Router(config-if)# mpls label protocol ldp	(Optional) Specifies MPLS LDP as the default label distribution protocol for the interface.
Step 6	exit Example: Router(config-if)# exit	(Optional) Exits to privileged EXEC mode.

Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers

Every packet that crosses the backbone carrier must be encapsulated, so that the packet includes MPLS labels. You can enable MPLS encapsulation for the entire router or just on the interface of the PE or CE router. To enable the encapsulation of packets, perform the following task.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls ip

4. interface type number

5. mpls ip

6. exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	mpls ip Example: Router(config)# mpls ip	Enables MPLS encapsulation for the router.
Step 4	interface type number Example: Router(config)# interface Ethernet5/0	(Optional) Specifies the interface to configure and enters interface configuration mode. The type argument specifies the type of interface to be configured. The number argument specifies the port, connector, or interface card number.
Step 5	mpls ip Example: Router(config-if)# mpls ip	(Optional) Enables MPLS encapsulation for the specified interface.
Step 6	exit Example: Router(config-if)# exit	(Optional) Exits to privileged EXEC mode.

Verifying the Carrier Supporting Carrier Configuration

The following commands verify the status of LDP sessions that were configured between the backbone carrier and customer carrier. Now the customer carrier ISP sites appear as a VPN customer to the backbone carrier.

SUMMARY STEPS

1. show mpls ldp discovery vrf vrf-name

2. show mpls ldp discovery all

DETAILED STEPS

Step 1

show mpls ldp discovery vrf vrf-name

Use this command to show that the LDP sessions are in VRF VPN1 of the PE router of the backbone carrier, for example:

Example:

Router# show mpls ldp discovery vrf vpn1 
Local LDP Identifier:
    10.0.0.0:0
Discovery Sources:
    Interfaces:
        Ethernet1/0 (ldp): xmit/recv
            LDP Id: 10.0.0.1:0
POS6/0 (ldp): xmit

Step 2

show mpls ldp discovery all

Use this command to list all LDP sessions in a router, for example:

Example:

Router# show mpls ldp discovery all
Local LDP Identifier:
    10.10.10.10:0
Discovery Sources:
    Interfaces:
        Ethernet1/5 (ldp): xmit/recv
            LDP Id: 10.5.5.5:0
VRF vpn1: Local LDP Identifier:
    10.0.0.1:0
Discovery Sources:
    Interfaces:
        Ethernet1/0 (ldp): xmit/recv
            LDP Id: 10.0.0.1:0
POS6/0 (ldp): xmit

The Local LDP Identifier field shows the LDP identifier for the local label switching router for this session. The Interfaces field displays the interfaces engaging in LDP discovery activity:

xmit indicates that the interface is transmitting LDP discovery hello packets.
recv indicates that the interface is receiving LDP discovery hello packets.

Configuration Examples for MPLS VPN CSC with LDP and IGP

MPLS VPN CSC Network with a Customer Who Is an ISP Example
MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider Example
MPLS VPN CSC Network That Contains Route Reflectors Example
MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example

MPLS VPN CSC Network with a Customer Who Is an ISP Example

The figure below shows a carrier supporting carrier network configuration where the customer carrier is an ISP. The customer carrier has two sites, each of which is a POP. The customer carrier connects these sites using a VPN service provided by the backbone carrier. The backbone carrier uses MPLS. The ISP sites use IP. To enable packet transfer between the ISP sites and the backbone carrier, the CE routers that connect the ISPs to the backbone carrier run MPLS.

Figure 6

Carrier Supporting Carrier Network with a Customer Carrier Who Is an ISP

The following examples show the configuration of each router in the carrier supporting carrier network. OSPF is used to connect the customer carrier to the backbone carrier.

CSC-CE1 Configuration
CSC-PE1 Configuration
CSC-PE2 Configuration
CSC-CE2 Configuration

CSC-CE1 Configuration

mpls label protocol ldp
!
interface Loopback0
 ip address 10.14.14.14 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 101 0 51 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM2/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 network 10.14.14.14 0.0.0.0 area 200
 network 10.15.0.0 0.255.255.255 area 200
 network 10.16.0.0 0.255.255.255 area 200

CSC-PE1 Configuration

ip cef distributed
!
ip vrf vpn1
 rd 100:0
 route-target export 100:0
 route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
 ip address 10.11.11.11 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface Loopback100
 ip vrf forwarding vpn1
 ip address 10.19.19.19 255.255.255.255
 no ip directed-broadcast
!
interface ATM1/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/1/0.1 
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 101 0 51 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 100
 log-adjacency-changes
 passive-interface ATM3/0/0.1
 passive-interface Loopback100
 network 10.11.11.11 0.0.0.0 area 100
 network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
 log-adjacency-changes
 redistribute bgp 100 metric-type 1 subnets
 network 10.19.19.19 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.12.12.12 remote-as 100
 neighbor 10.12.12.12 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.12.12.12 activate
 neighbor 10.12.12.12 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.12.12.12 activate
 neighbor 10.12.12.12 send-community extended
 exit-address-family
 !
 address-family ipv4 vrf vpn1
 redistribute ospf 200 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

CSC-PE2 Configuration

ip cef distributed
!
ip vrf vpn1
 rd 100:0
 route-target export 100:0
 route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
 ip address 10.12.12.12 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface Loopback100
 ip vrf forwarding vpn1
 ip address 10.20.20.20 255.255.255.255
 no ip directed-broadcast
!
interface ATM0/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM0/1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 100
 log-adjacency-changes
 passive-interface ATM3/0/0.1
 passive-interface Loopback100
 network 10.12.12.12 0.0.0.0 area 100
 network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
 log-adjacency-changes
 redistribute bgp 100 metric-type 1 subnets
 network 10.20.20.20 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.11.11.11 remote-as 100
 neighbor 10.11.11.11 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.11.11.11 activate
 neighbor 10.11.11.11 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.11.11.11 activate
 neighbor 10.11.11.11 send-community extended
 exit-address-family
 !
 address-family ipv4 vrf vpn1
 redistribute ospf 200 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

CSC-CE2 Configuration

ip cef
!         
mpls label protocol ldp
!
interface Loopback0
 ip address 10.16.16.16 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM5/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 network 10.16.16.16 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
 network 10.0.0.0 0.255.255.255 area 200

MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider Example

The figure below shows a carrier supporting carrier network configuration where the customer carrier is an MPLS VPN provider. The customer carrier has two sites. The backbone carrier and the customer carrier use MPLS. The IBGP sessions exchange the external routing information of the ISP.

Figure 7

Carrier Supporting Carrier Network with a Customer Carrier Who Is an MPLS VPN Provider

The following configuration examples show the configuration of each router in the carrier supporting carrier network. OSPF is the protocol used to connect the customer carrier to the backbone carrier.

CE1 Configuration
PE1 Configuration
CSC-CE1 Configuration
CSC-PE1 Configuration
CSC-PE2 Configuration
CSC-CE2 Configuration
PE2 Configuration
CE2 Configuration

CE1 Configuration

ip cef
!
interface Loopback0
 ip address 10.17.17.17 255.255.255.255
 no ip directed-broadcast
!
interface Ethernet0/1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!
router ospf 300
 log-adjacency-changes
 redistribute bgp 300 subnets
 passive-interface Ethernet0/1
 network 10.17.17.17 0.0.0.0 area 300
!
router bgp 300
 no synchronization
 bgp log-neighbor-changes
 timers bgp 10 30
 redistribute connected
 redistribute ospf 300 match internal external 1 external 2
 neighbor 10.0.0.1 remote-as 200
 neighbor 10.0.0.1 advertisement-interval 5
 no auto-summary

PE1 Configuration

ip cef
!         
ip vrf vpn2
 rd 200:1
 route-target export 200:1
 route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
 ip address 10.13.13.13 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface Ethernet3/0
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 passive-interface Ethernet3/0
 network 10.13.13.13 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 200
 no bgp default ipv4-unicast
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.15.15.15 remote-as 200
 neighbor 10.15.15.15 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.15.15.15 activate
 neighbor 10.15.15.15 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.15.15.15 activate
 neighbor 10.15.15.15 send-community extended
 exit-address-family
 !        
 address-family ipv4 vrf vpn2
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 neighbor 10.0.0.2 advertisement-interval 5
 no auto-summary
 no synchronization
 exit-address-family

CSC-CE1 Configuration

mpls label protocol ldp
!
interface Loopback0
 ip address 10.14.14.14 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 101 0 51 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM2/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 network 10.14.14.14 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
 network 10.0.0.0 0.255.255.255 area 200

CSC-PE1 Configuration

ip cef distributed
!
ip vrf vpn1
 rd 100:0
 route-target export 100:0
 route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
 ip address 11.11.11.11 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface Loopback100
 ip vrf forwarding vpn1
 ip address 10.19.19.19 255.255.255.255
 no ip directed-broadcast
!
interface ATM1/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/1/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 101 0 51 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 100
 log-adjacency-changes
 passive-interface ATM3/0/0.1
 passive-interface Loopback100
 network 10.11.11.11 0.0.0.0 area 100
 network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
 log-adjacency-changes
 redistribute bgp 100 metric-type 1 subnets
 network 10.19.19.19 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.12.12.12 remote-as 100
 neighbor 10.12.12.12 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.12.12.12 activate
 neighbor 10.12.12.12 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.12.12.12 activate
 neighbor 10.12.12.12 send-community extended
 exit-address-family
 !
 address-family ipv4 vrf vpn1
 redistribute ospf 200 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

CSC-PE2 Configuration

ip cef distributed
!
ip vrf vpn1
 rd 100:0
 route-target export 100:0
 route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
 ip address 10.12.12.12 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface Loopback100
 ip vrf forwarding vpn1
 ip address 10.20.20.20 255.255.255.255
 no ip directed-broadcast
!
interface ATM0/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM0/1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 100
 log-adjacency-changes
 passive-interface ATM3/0/0.1
 passive-interface Loopback100
 network 10.12.12.12 0.0.0.0 area 100
 network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
 log-adjacency-changes
 redistribute bgp 100 metric-type 1 subnets
 network 10.20.20.20 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.11.11.11 remote-as 100
 neighbor 10.11.11.11 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.11.11.11 activate
 neighbor 10.11.11.11 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.11.11.11 activate
 neighbor 10.11.11.11 send-community extended
 exit-address-family
 !
 address-family ipv4 vrf vpn1
 redistribute ospf 200 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

CSC-CE2 Configuration

ip cef
!         
mpls label protocol ldp
!
interface Loopback0
 ip address 10.16.16.16 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
interface ATM5/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 network 10.16.16.16 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
 network 10.0.0.0 0.255.255.255 area 200

PE2 Configuration

ip cef
ip cef accounting non-recursive 
!         
ip vrf vpn2
 rd 200:1
 route-target export 200:1
 route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
 ip address 10.15.15.15 255.255.255.255
 no ip directed-broadcast
!
interface Ethernet3/0
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
!
interface ATM5/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!
router ospf 200
 log-adjacency-changes
 redistribute connected subnets
 passive-interface Ethernet3/0
 network 10.15.15.15 0.0.0.0 area 200
 network 10.0.0.0 0.255.255.255 area 200
!
router bgp 200
 no bgp default ipv4-unicast
 bgp log-neighbor-changes
 timers bgp 10 30
 neighbor 10.13.13.13 remote-as 200
 neighbor 10.13.13.13 update-source Loopback0
 !
 address-family ipv4
 neighbor 10.13.13.13 activate
 neighbor 10.13.13.13 send-community extended
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor 10.13.13.13 activate
 neighbor 10.13.13.13 send-community extended
 exit-address-family
 !
 address-family ipv4 vrf vpn2
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 neighbor 10.0.0.2 advertisement-interval 5
 no auto-summary
 no synchronization
 exit-address-family

CE2 Configuration

ip cef
!
interface Loopback0
 ip address 10.18.18.18 255.255.255.255
 no ip directed-broadcast
!
interface Ethernet0/1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!
router ospf 300
 log-adjacency-changes
 redistribute bgp 300 subnets
 passive-interface Ethernet0/1
 network 10.18.18.18 0.0.0.0 area 300
!
router bgp 300
 no synchronization
 bgp log-neighbor-changes
 timers bgp 10 30
 redistribute connected
 redistribute ospf 300 match internal external 1 external 2
 neighbor 10.0.0.1 remote-as 200
 neighbor 10.0.0.1 advertisement-interval 5
 no auto-summary

MPLS VPN CSC Network That Contains Route Reflectors Example

The figure below shows a carrier supporting carrier network configuration that contains route reflectors. The customer carrier has two sites.

Figure 8

Carrier Supporting Carrier Network that Contains Route Reflectors

Note

A connection between route reflectors (RRs) is not necessary.

The following configuration examples show the configuration of each router in the carrier supporting carrier network. Note the following:

The router IP addresses are abbreviated for ease of reading. For example, the loopback address for PE 1 is 25, which is equivalent to 10.25.25.25.
The following list shows the loopback addresses for the CSC-PE routers:
- CSC-PE1 (75K-37-3): loopback 0 = 10.15.15.15, loopback 1 = 10.18.18.18
- CSC-PE2 (75K-38-3): loopback 0 = 10.16.16.16, loopback 1 = 10.20.20.20

Backbone Carrier Configuration
Customer Carrier Site 1 Configuration
Customer Carrier Site 2 Configuration

Backbone Carrier Configuration

Route Reflector 1 (72K-37-1) Configuration
Route Reflector 2 (72K-38-1) Configuration
CSC-PE1 (75K-37-3) Configuration
CSC-PE2 (75K-38-3) Configuration

Route Reflector 1 (72K-37-1) Configuration

interface Loopback0
 ip address 10.13.13.13 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface ATM1/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM1/0.1 mpls
ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
interface ATM1/1
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM1/1.1 mpls
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
router ospf 100
 auto-cost reference-bandwidth 10000
 network 10.0.0.0 0.255.255.255 area 100
 network 10.1.0.0 0.255.255.255 area 100
 network 10.2.0.0 0.255.255.255 area 100
!         
router bgp 100
 no synchronization
 no bgp default ipv4-unicast
 bgp cluster-id 1
 redistribute static
 neighbor 10.15.15.15 remote-as 100
 neighbor 10.15.15.15 update-source Loopback0
 neighbor 10.16.16.16 remote-as 100
 neighbor 10.16.16.16 update-source Loopback0
 !        
 address-family ipv4 vrf vpn1
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.15.15.15 activate
 neighbor 10.15.15.15 route-reflector-client
 neighbor 10.15.15.15 send-community extended
 neighbor 10.16.16.16 activate
 neighbor 10.16.16.16 route-reflector-client
 neighbor 10.16.16.16 send-community extended
 bgp scan-time import 5
 exit-address-family

Route Reflector 2 (72K-38-1) Configuration

interface Loopback0
 ip address 10.14.14.14 255.255.255.255
 no ip directed-broadcast
 no ip mroute-cache
!         
interface ATM1/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM1/0.1 mpls
 ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
interface ATM1/1
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM1/1.1 mpls
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
router ospf 100
 auto-cost reference-bandwidth 10000
 network 10.0.0.0 0.255.255.255 area 100
 network 10.1.0 0.255.255.255 area 100
 network 10.2.0.0 0.255.255.255 area 100
!         
router bgp 100
 no synchronization
 no bgp default ipv4-unicast
 bgp cluster-id 1
 redistribute static
 neighbor 10.15.15.15 remote-as 100
 neighbor 10.15.15.15 update-source Loopback0
 neighbor 10.16.16.16 remote-as 100
 neighbor 10.16.16.16 update-source Loopback0
 !        
 address-family ipv4 vrf vpn1
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.15.15.15 activate
 neighbor 10.15.15.15 route-reflector-client
 neighbor 10.15.15.15 send-community extended
 neighbor 10.16.16.16 activate
 neighbor 10.16.16.16 route-reflector-client
 neighbor 10.16.16.16 send-community extended
 bgp scan-time import 5
 exit-address-family

CSC-PE1 (75K-37-3) Configuration

ip cef distributed
!         
ip vrf vpn1
 rd 100:1 
 route-target export 100:1
 route-target import 100:1
!         
interface Loopback0
 ip address 10.15.15.15 255.255.255.255
 no ip directed-broadcast
!         
interface Loopback1
 ip vrf forwarding vpn1
 ip address 10.18.18.18 255.255.255.255
 no ip directed-broadcast
!         
interface Ethernet0/0/1
 ip vrf forwarding vpn1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip route-cache distributed
 mpls label protocol ldp
 mpls ip
!         
interface ATM1/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM1/1/0.1 mpls
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 6 32 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!         
interface ATM3/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM3/1/0.1 mpls
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
router ospf 100
 auto-cost reference-bandwidth 10000
 network 10.0.0.0 0.255.255.255 area 100
 network 10.1.0.0 0.255.255.255 area 100
 network 10.2.0.0 0.255.255.255 area 100
 network 10.3.0.0 0.255.255.255 area 100
 network 10.4.0.0 0.255.255.255 area 100
!         
router ospf 1 vrf vpn1
 redistribute bgp 100 metric-type 1 subnets
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
!         
router bgp 100
 no bgp default ipv4-unicast
 bgp log-neighbor-changes
 neighbor 10.13.13.13 remote-as 100
 neighbor 10.13.13.13 update-source Loopback0
 neighbor 10.14.14.14 remote-as 100
 neighbor 10.14.14.14 update-source Loopback0
 !        
 address-family ipv4
 redistribute static
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.13.13.13 activate
 neighbor 10.13.13.13 send-community extended
 neighbor 10.14.14.14 activate
 neighbor 10.14.14.14 send-community extended
 exit-address-family
 !        
 address-family ipv4 vrf vpn1
 redistribute ospf 1 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

CSC-PE2 (75K-38-3) Configuration

ip cef distributed
!         
ip vrf vpn1
 rd 100:1 
 route-target export 100:1
 route-target import 100:1
!         
interface Loopback0
 ip address 10.16.16.16 255.255.255.255
 no ip directed-broadcast
!         
interface Loopback1
 ip vrf forwarding vpn1
 ip address 10.20.20.20 255.255.255.255
 no ip directed-broadcast
!         
interface ATM0/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM0/1/0.1 mpls
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
interface ATM2/1/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM2/1/0.1 mpls
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls atm vpi 2-5
 mpls ip
!         
interface ATM3/0/0
 no ip address
 no ip directed-broadcast
 no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM3/0/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 6 32 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!         
interface ATM3/1/0
 no ip address
 no ip directed-broadcast
no ip route-cache distributed
 atm clock INTERNAL
 atm sonet stm-1
 no atm enable-ilmi-trap
 no atm ilmi-keepalive
!         
interface ATM3/1/0.1 point-to-point
 ip vrf forwarding vpn1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 101 6 33 aal5snap
 no atm enable-ilmi-trap
 mpls label protocol ldp
 mpls ip
!         
router ospf 100
 auto-cost reference-bandwidth 10000
 network 10.0.0.0 0.255.255.255 area 100
 network 10.0.0.0 0.255.255.255 area 100
 network 10.0.0.0 0.255.255.255 area 100
 network 10.0.0.0 0.255.255.255 area 100
 network 10.0.0.0 0.255.255.255 area 100
!         
router ospf 1 vrf vpn1
 redistribute bgp 100 metric-type 1 subnets
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
!         
router bgp 100
 no bgp default ipv4-unicast
 bgp log-neighbor-changes
 neighbor 10.13.13.13 remote-as 100
 neighbor 10.13.13.13 update-source Loopback0
 neighbor 10.14.14.14 remote-as 100
 neighbor 10.14.14.14 update-source Loopback0
 !        
 address-family ipv4
 redistribute static
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.13.13.13 activate
 neighbor 10.13.13.13 send-community extended
 neighbor 10.14.14.14 activate
 neighbor 10.14.14.14 send-community extended
 exit-address-family
 !        
 address-family ipv4 vrf vpn1
 redistribute ospf 1 match internal external 1 external 2
 no auto-summary
 no synchronization
 exit-address-family

Customer Carrier Site 1 Configuration

PE1 (72K-36-8) Configuration
CSC-CE1 (72K-36-9) Configuration
PE2 (72K-36-7) Configuration
Route Reflector 3 (36K-38-4) Configuration
CE1 (36K-36-1) Configuration

PE1 (72K-36-8) Configuration

ip cef
!
ip vrf vpn2
 rd 200:1 
 route-target export 200:1
 route-target import 200:1
no mpls ip propagate-ttl
!         
interface Loopback0
 ip address 10.25.25.25 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
 mpls label protocol ldp
 mpls ip
!         
interface Ethernet3/0
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
!         
interface Ethernet3/1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
 mpls label protocol ldp
 mpls ip
!         
interface Ethernet3/2
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
!         
router bgp 200
 neighbor 10.22.22.22 remote-as 200
 neighbor 10.22.22.22 update-source Loopback0
 neighbor 10.23.23.23 remote-as 200
 neighbor 10.23.23.23 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 redistribute connected
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.22.22.22 activate
 neighbor 10.22.22.22 send-community extended
 neighbor 10.23.23.23 activate
 neighbor 10.23.23.23 send-community extended
 exit-address-family

CSC-CE1 (72K-36-9) Configuration

ip cef
no ip domain-lookup
!         
interface Loopback0
 ip address 10.11.11.11 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM1/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 6 32 aal5snap
mpls label protocol ldp
mpls ip
!         
interface ATM2/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM2/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 50 aal5snap
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/0
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/1
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101

PE2 (72K-36-7) Configuration

ip cef
!
ip vrf vpn2
 rd 200:1 
 route-target export 200:1
 route-target import 200:1
no mpls ip propagate-ttl
!         
interface Loopback0
 ip address 10.24.24.24 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface Ethernet3/0
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/1
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
!         
interface Ethernet3/2
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/3
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
!         
router bgp 200
 neighbor 10.22.22.22 remote-as 200
 neighbor 10.22.22.22 update-source Loopback0
 neighbor 10.23.23.23 remote-as 200
 neighbor 10.23.23.23 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.22.22.22 activate
 neighbor 10.22.22.22 send-community extended
 neighbor 10.23.23.23 activate
 neighbor 10.23.23.23 send-community extended
 exit-address-family

Route Reflector 3 (36K-38-4) Configuration

ip cef    
!         
interface Loopback0
 ip address 10.23.23.23 255.255.255.255
!         
interface Ethernet1/1
 ip address 10.0.0.1 255.0.0.0
 mpls label protocol ldp
 mpls ip
!         
interface Ethernet1/2
 ip address 10.0.0.1 255.0.0.0
 mpls label protocol ldp
 mpls ip
!         
interface ATM3/0
 no ip address
 no ip mroute-cache
 atm clock INTERNAL
 no atm scrambling cell-payload
 no atm ilmi-keepalive
!         
interface ATM3/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 atm pvc 100 0 55 aal5snap
 mpls label protocol ldp
 mpls ip
!         
router ospf 1
 log-adjacency-changes
 network 10.0.0.0 0.255.255.255 area 101
 network 10.1.0.0 0.255.255.255 area 101
 network 10.2.0.0 0.255.255.255 area 101
 network 10.3.0.0 0.255.255.255 area 101
!         
router bgp 200
 no synchronization
 no bgp default ipv4-unicast
 bgp cluster-id 2
 redistribute static
 neighbor 10.21.21.21 remote-as 200
 neighbor 10.21.21.21 update-source Loopback0
 neighbor 10.24.24.24 remote-as 200
 neighbor 10.24.24.24 update-source Loopback0
 neighbor 10.25.25.25 remote-as 200
 neighbor 10.25.25.25 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.21.21.21 activate
 neighbor 10.21.21.21 route-reflector-client
 neighbor 10.21.21.21 send-community extended
 neighbor 10.24.24.24 activate
 neighbor 10.24.24.24 route-reflector-client
 neighbor 10.24.24.24 send-community extended
 neighbor 10.25.25.25 activate
 neighbor 10.25.25.25 route-reflector-client
 neighbor 10.25.25.25 send-community extended
 exit-address-family

CE1 (36K-36-1) Configuration

ip cef
!         
interface Loopback0
 ip address 10.28.28.28 255.255.255.255
 no ip directed-broadcast
!         
interface Ethernet0/1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!         
interface Ethernet0/2
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!         
router bgp 300
 network 10.0.0.0
 network 10.0.0.0
 network 10.0.0.0
 neighbor 10.0.0.1 remote-as 200
 neighbor 10.0.0.1 remote-as 200

Customer Carrier Site 2 Configuration

CSC-CE3 (72K-36-6) Configuration
PE3 (72K-36-4) Configuration
CSC-CE4 (72K-36-5) Configuration
Route Reflector 4 (36K-38-5) Configuration
CE2 (36K-36-2) Configuration
CE3 (36K-36-3) Configuration

CSC-CE3 (72K-36-6) Configuration

ip cef
!         
interface Loopback0
 ip address 10.12.12.12 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface ATM1/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM1/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 6 32 aal5snap
mpls label protocol ldp
 mpls ip
!         
interface POS2/0
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 encapsulation ppp
mpls label protocol ldp
mpls ip
!         
interface ATM5/0
 no ip address
 no ip directed-broadcast
 no ip mroute-cache
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM5/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 40 aal5snap
 mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.1.0.0 0.255.255.255 area 101
 network 10.2.0.0 0.255.255.255 area 101
 network 10.3.0.0 0.255.255.255 area 101

PE3 (72K-36-4) Configuration

ip cef
!         
ip vrf vpn2
 rd 200:1 
 route-target export 200:1
 route-target import 200:1
!         
! 
interface Loopback0
 ip address 10.21.21.21 255.255.255.255
 no ip directed-broadcast
!         
interface Ethernet3/0
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
!         
interface Ethernet3/1
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
!         
interface Ethernet3/2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
mpls label protocol ldp
mpls ip
!         
interface ATM5/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM5/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 40 aal5snap
mpls label protocol ldp
mpls ip
!         
interface ATM6/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM6/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 20 aal5snap
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.1.0.0 0.255.255.255 area 101
 network 10.2.0.0 0.255.255.255 area 101
 network 10.3.0.0 0.255.255.255 area 101
!         
router bgp 200
 neighbor 10.22.22.22 remote-as 200
 neighbor 10.22.22.22 update-source Loopback0
 neighbor 10.23.23.23 remote-as 200
 neighbor 10.23.23.23 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 redistribute connected
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.22.22.22 activate
 neighbor 10.22.22.22 send-community extended
 neighbor 10.23.23.23 activate
 neighbor 10.23.23.23 send-community extended
 exit-address-family

CSC-CE4 (72K-36-5) Configuration

ip cef
!         
interface Loopback0
 ip address 10.10.10.10 255.255.255.255
 no ip directed-broadcast
!         
interface POS4/0
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 encapsulation ppp
mpls label protocol ldp
mpls ip
 clock source internal
!         
interface ATM5/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM5/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 0 20 aal5snap
mpls label protocol ldp
mpls ip
!         
interface ATM6/0
 no ip address
 no ip directed-broadcast
 atm clock INTERNAL
 no atm ilmi-keepalive
!         
interface ATM6/0.1 point-to-point
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 atm pvc 100 6 33 aal5snap
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.1.0.0 0.255.255.255 area 101
 network 10.2.0.0 0.255.255.255 area 101
 network 10.3.0.0 0.255.255.255 area 101

Route Reflector 4 (36K-38-5) Configuration

ip cef
!         
interface Loopback0
 ip address 10.22.22.22 255.255.255.255
!         
interface Ethernet0/1
 ip address 10.0.0.2 255.0.0.0
 mpls label protocol ldp
 mpls ip
!         
interface ATM2/0
 no ip address
 no ip mroute-cache
 atm clock INTERNAL
 no atm scrambling cell-payload
 no atm ilmi-keepalive
!         
interface ATM2/0.1 point-to-point
 ip address 10.0.0.1 255.0.0.0
 atm pvc 100 0 55 aal5snap
 mpls label protocol ldp
 mpls ip
!         
router ospf 1
 log-adjacency-changes
 network 10.0.0.0 0.255.255.255 area 101
 network 10.1.0.0 0.255.255.255 area 101
 network 10.2.0.0 0.255.255.255 area 101
!         
router bgp 200
 no synchronization
 no bgp default ipv4-unicast
 bgp cluster-id 2
 redistribute static
 neighbor 10.21.21.21 remote-as 200
 neighbor 10.21.21.21 update-source Loopback0
 neighbor 10.24.24.24 remote-as 200
 neighbor 10.24.24.24 update-source Loopback0
 neighbor 10.25.25.25 remote-as 200
 neighbor 10.25.25.25 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.21.21.21 activate
 neighbor 10.21.21.21 route-reflector-client
 neighbor 10.21.21.21 send-community extended
 neighbor 10.24.24.24 activate
 neighbor 10.24.24.24 route-reflector-client
 neighbor 10.24.24.24 send-community extended
 neighbor 10.25.25.25 activate
 neighbor 10.25.25.25 route-reflector-client
 neighbor 10.25.25.25 send-community extended
 exit-address-family

CE2 (36K-36-2) Configuration

ip cef
!
interface Loopback0
 ip address 10.26.26.26 255.255.255.255
 no ip directed-broadcast
!         
interface Ethernet0/1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!         
interface Ethernet0/2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
!         
router ospf 300
 redistribute bgp 300
 network 10.0.0.0 0.255.255.255 area 300
 network 10.0.0.0 0.255.255.255 area 300
!         
router bgp 300
 network 10.0.0.0
 network 10.1.0.0
 network 10.2.0.0
 neighbor 10.0.0.1 remote-as 200

CE3 (36K-36-3) Configuration

ip cef
!         
interface Loopback0
 ip address 10.27.27.27 255.255.255.255
 no ip directed-broadcast
!         
interface Ethernet1/1
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!         
interface Ethernet1/2
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
!         
router ospf 300
 redistribute bgp 300
 network 10.0.0.0 0.255.255.255 area 300
 network 10.0.0.0 0.255.255.255 area 300
!         
router bgp 300
 network 10.0.0.0
 network 10.1.0.0
 network 10.2.0.0
 neighbor 10.0.0.1 remote-as 200

MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example

The figure below shows a carrier supporting carrier network configuration where the customer carrier has VPNs at the network edge.

Figure 9

Carrier Supporting Carrier Network

Backbone Carrier Configuration
Customer Carrier Site 1 Configuration
Customer Carrier Site 2 Configuration

CSC-PE1 (72K-36-9) Configuration

ip cef 
! 
ip vrf vpn1 
rd 100:0 
route-target export 100:0 
route-target import 100:0 
mpls label protocol ldp 
! 
! 
interface Loopback0 
ip address 10.14.14.14 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface Loopback100 
ip vrf forwarding vpn1 
ip address 10.22.22.22 255.255.255.255 
no ip directed-broadcast 
! 
interface ATM1/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM1/0.1 point-to-point 
ip address 10.1.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/0.2 point-to-point 
ip address 10.2.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/0.3 point-to-point 
ip address 10.3.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM2/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM2/0.1 point-to-point 
ip vrf forwarding vpn1 
ip address 10.15.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM2/0.2 point-to-point 
ip vrf forwarding vpn1 
ip address 10.16.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM2/0.3 point-to-point 
ip vrf forwarding vpn1 
ip address 10.17.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 100 
log-adjacency-changes 
redistribute connected subnets 
passive-interface ATM2/0.1 
passive-interface ATM2/0.2 
passive-interface ATM2/0.3 
passive-interface Loopback100 
network 10.14.14.14 0.0.0.0 area 100 
network 10.1.0.0 0.0.255.255 area 100 
network 10.2.0.0 0.0.255.255 area 100 
network 10.3.0.0 0.0.255.255 area 100 
! 
router ospf 200 vrf vpn1 
log-adjacency-changes 
redistribute connected subnets 
redistribute bgp 100 metric-type 1 subnets 
network 10.22.22.22 0.0.0.0 area 200 
network 10.15.0.0 0.0.255.255 area 200 
network 10.16.0.0 0.0.255.255 area 200 
network 10.17.0.0 0.0.255.255 area 200 
! 
router bgp 100 
bgp log-neighbor-changes 
timers bgp 10 30 
neighbor 10.11.11.11 remote-as 100 
neighbor 10.11.11.11 update-source Loopback0 
! 
address-family ipv4 
neighbor 10.11.11.11 activate 
neighbor 10.11.11.11 send-community extended 
no synchronization 
exit-address-family 
! 
address-family vpnv4 
neighbor 10.11.11.11 activate 
neighbor 10.11.11.11 send-community extended 
exit-address-family 
! 
address-family ipv4 vrf vpn1 
redistribute ospf 200 match internal external 1 external 2 
no auto-summary 
no synchronization 
exit-address-family

P1 (75K-37-3) Configuration

ip cef distributed 
! 
mpls label protocol ldp 
! 
interface Loopback0 
ip address 10.12.12.12 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface ATM1/1/0 
no ip address 
no ip directed-broadcast 
ip route-cache distributed 
atm clock INTERNAL 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM1/1/0.1 point-to-point 
ip address 10.7.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 103 0 53 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/1/0.2 point-to-point 
ip address 10.8.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 104 0 54 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/1/0.3 point-to-point 
ip address 10.9.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 105 0 55 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM3/0/0 
no ip address 
no ip directed-broadcast 
ip route-cache distributed 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM3/0/0.1 point-to-point 
ip address 10.1.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
mpls accounting experimental input 
tag-switching ip 
! 
interface ATM3/0/0.2 point-to-point 
ip address 10.2.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM3/0/0.3 point-to-point 
ip address 10.3.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 100 
log-adjacency-changes 
redistribute connected subnets 
network 10.12.12.12 0.0.0.0 area 100 
network 10.1.0.0 0.0.255.255 area 100 
network 10.2.0.0 0.0.255.255 area 100 
network 10.3.0.0 0.0.255.255 area 100 
network 10.7.0.0 0.0.255.255 area 100 
network 10.8.0.0 0.0.255.255 area 100 
network 10.9.0.0 0.0.255.255 area 100

P2 (75K-38-3) Configuration

ip cef distributed 
! 
mpls label protocol ldp 
! 
interface Loopback0 
ip address 10.13.13.13 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface ATM0/1/0 
no ip address 
no ip directed-broadcast 
ip route-cache distributed 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM0/1/0.1 point-to-point 
ip address 10.7.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 103 0 53 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM0/1/0.2 point-to-point 
ip address 10.8.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 104 0 54 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM0/1/0.3 point-to-point 
ip address 10.9.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 105 0 55 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM3/1/0 
no ip address 
no ip directed-broadcast 
ip route-cache distributed 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM3/1/0.1 point-to-point 
ip address 10.4.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM3/1/0.2 point-to-point 
ip address 10.5.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM3/1/0.3 point-to-point 
ip address 10.6.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 100 
log-adjacency-changes 
redistribute connected subnets 
network 10.13.13.13 0.0.0.0 area 100 
network 10.4.0.0 0.0.255.255 area 100 
network 10.5.0.0 0.0.255.255 area 100 
network 10.6.0.0 0.0.255.255 area 100 
network 10.7.0.0 0.0.255.255 area 100 
network 10.8.0.0 0.0.255.255 area 100 
network 10.9.0.0 0.0.255.255 area 100 
!

CSC-PE2 (72K-36-5) Configuration

ip cef 
! 
ip vrf vpn1 
rd 100:0 
route-target export 100:0 
route-target import 100:0 
mpls label protocol ldp 
! 
interface Loopback0 
ip address 10.11.11.11 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface Loopback100 
ip vrf forwarding vpn1 
ip address 10.23.23.23 255.255.255.255 
no ip directed-broadcast 
! 
interface ATM5/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM5/0.1 point-to-point 
ip vrf forwarding vpn1 
ip address 10.18.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.2 point-to-point 
ip vrf forwarding vpn1 
ip address 10.19.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.3 point-to-point 
ip vrf forwarding vpn1 
ip address 10.20.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM6/0.1 point-to-point 
ip address 10.4.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0.2 point-to-point 
ip address 10.5.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0.3 point-to-point 
ip address 10.6.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 100 
log-adjacency-changes 
redistribute connected subnets 
passive-interface ATM5/0.1 
passive-interface ATM5/0.2 
passive-interface ATM5/0.3 
passive-interface Loopback100 
network 10.11.11.11 0.0.0.0 area 100 
network 10.4.0.0 0.0.255.255 area 100 
network 10.5.0.0 0.0.255.255 area 100 
network 10.6.0.0 0.0.255.255 area 100 
! 
router ospf 200 vrf vpn1 
log-adjacency-changes 
redistribute connected subnets 
redistribute bgp 100 metric-type 1 subnets 
network 10.23.23.23 0.0.0.0 area 200 
network 10.18.0.0 0.0.255.255 area 200 
network 10.19.0.0 0.0.255.255 area 200 
network 10.20.0.0 0.0.255.255 area 200 
! 
router bgp 100 
bgp log-neighbor-changes 
timers bgp 10 30 
neighbor 10.14.14.14 remote-as 100 
neighbor 10.14.14.14 update-source Loopback0 
! 
address-family ipv4 
neighbor 10.14.14.14 activate 
neighbor 10.14.14.14 send-community extended 
no synchronization 
exit-address-family 
! 
address-family vpnv4 
neighbor 10.14.14.14 activate 
neighbor 10.14.14.14 send-community extended 
exit-address-family 
! 
address-family ipv4 vrf vpn1 
redistribute ospf 200 match internal external 1 external 2 
no auto-summary 
no synchronization 
exit-address-family

Customer Carrier Site 1 Configuration

CSC-CE1 (72K-36-8) Configuration
PE2 (72K-36-7) Configuration
CE1 (36K-36-1) Configuration

CSC-CE1 (72K-36-8) Configuration

ip cef 
! 
mpls label protocol ldp 
!
interface Loopback0 
ip address 10.15.15.15 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface ATM1/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM1/0.1 point-to-point 
ip address 10.15.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/0.2 point-to-point 
ip address 10.16.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM1/0.3 point-to-point 
ip address 10.17.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface Ethernet3/1 
ip address 10.10.0.2 255.255.0.0 
no ip directed-broadcast 
no ip mroute-cache 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 200 
log-adjacency-changes 
redistribute connected subnets 
network 10.15.15.15 0.0.0.0 area 200 
network 10.10.0.0 0.0.255.255 area 200 
network 10.15.0.0 0.0.255.255 area 200 
network 10.16.0.0 0.0.255.255 area 200 
network 10.17.0.0 0.0.255.255 area 200

PE2 (72K-36-7) Configuration

ip cef
!
ip vrf vpn2
 rd 200:1 
 route-target export 200:1
 route-target import 200:1
no mpls ip propagate-ttl
!         
interface Loopback0
 ip address 10.24.24.24 255.255.255.255
 no ip directed-broadcast
 no ip route-cache
 no ip mroute-cache
!         
interface Ethernet3/0
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/1
 ip vrf forwarding vpn2
 ip address 10.0.0.1 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
!         
interface Ethernet3/2
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
interface Ethernet3/3
 ip address 10.0.0.2 255.0.0.0
 no ip directed-broadcast
 no ip mroute-cache
mpls label protocol ldp
mpls ip
!         
router ospf 1
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
 network 10.0.0.0 0.255.255.255 area 101
!         
router bgp 200
 neighbor 10.22.22.22 remote-as 200
 neighbor 10.22.22.22 update-source Loopback0
 neighbor 10.23.23.23 remote-as 200
 neighbor 10.23.23.23 update-source Loopback0
 !        
 address-family ipv4 vrf vpn2
 neighbor 10.0.0.2 remote-as 300
 neighbor 10.0.0.2 activate
 neighbor 10.0.0.2 as-override
 no auto-summary
 no synchronization
 exit-address-family
 !        
 address-family vpnv4
 neighbor 10.22.22.22 activate
 neighbor 10.22.22.22 send-community extended
 neighbor 10.23.23.23 activate
 neighbor 10.23.23.23 send-community extended
 exit-address-family

CE1 (36K-36-1) Configuration

ip cef 
! 
interface Loopback0 
ip address 10.19.19.19 255.255.255.255 
no ip directed-broadcast 
! 
interface Ethernet0/2 
ip address 30.35.0.1 255.255.0.0 
no ip directed-broadcast 
! 
router ospf 300 
log-adjacency-changes 
redistribute connected subnets 
redistribute bgp 300 subnets 
passive-interface Ethernet0/2 
network 10.19.19.19 0.0.0.0 area 300 
! 
router bgp 300 
no synchronization 
bgp log-neighbor-changes 
timers bgp 10 30 
redistribute connected 
redistribute ospf 300 match internal external 1 external 2 
neighbor 10.35.0.2 remote-as 200 
neighbor 10.35.0.2 advertisement-interval 5 
no auto-summary

Customer Carrier Site 2 Configuration

CSC-CE2 (72K-36-4) Configuration
PE2 (72K-36-6) Configuration
CE2 (36K-38-4) Configuration
CE3 (36K-38-5) Configuration

CSC-CE2 (72K-36-4) Configuration

ip cef 
! 
mpls label protocol ldp 
! 
interface Loopback0 
ip address 10.17.17.17 255.255.255.255 
no ip directed-broadcast 
! 
interface ATM5/0 
no ip address 
no ip directed-broadcast 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM5/0.1 point-to-point 
ip address 10.11.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.2 point-to-point 
ip address 10.12.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.3 point-to-point 
ip address 10.13.0.2 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0 
no ip address 
no ip directed-broadcast 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM6/0.1 point-to-point 
ip address 10.18.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0.2 point-to-point 
ip address 10.19.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM6/0.3 point-to-point 
ip address 10.20.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 200 
log-adjacency-changes 
redistribute connected subnets 
network 10.17.17.17 0.0.0.0 area 200 
network 10.11.0.0 0.0.255.255 area 200 
network 10.12.0.0 0.0.255.255 area 200 
network 10.13.0.0 0.0.255.255 area 200 
network 10.18.0.0 0.0.255.255 area 200 
network 10.19.0.0 0.0.255.255 area 200 
network 10.20.0.0 0.0.255.255 area 200

PE2 (72K-36-6) Configuration

ip cef 
! 
ip vrf customersite 
rd 200:1 
route-target export 200:1 
route-target import 200:1 
mpls label protocol ldp 
! 
interface Loopback0 
ip address 10.18.18.18 255.255.255.255 
no ip directed-broadcast 
no ip route-cache 
no ip mroute-cache 
! 
interface Ethernet3/0 
ip vrf forwarding customersite 
ip address 10.29.0.2 255.255.0.0 
no ip directed-broadcast 
! 
interface Ethernet3/1 
ip vrf forwarding customersite 
ip address 10.30.0.2 255.255.0.0 
no ip directed-broadcast 
! 
interface ATM5/0 
no ip address 
no ip directed-broadcast 
no ip mroute-cache 
atm clock INTERNAL 
atm sonet stm-1 
no atm enable-ilmi-trap 
no atm ilmi-keepalive 
! 
interface ATM5/0.1 point-to-point 
ip address 10.11.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 100 0 50 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.2 point-to-point 
ip address 10.12.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 101 0 51 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
interface ATM5/0.3 point-to-point 
ip address 10.13.0.1 255.255.0.0 
no ip directed-broadcast 
atm pvc 102 0 52 aal5snap 
no atm enable-ilmi-trap 
mpls label protocol ldp 
tag-switching ip 
! 
router ospf 200 
log-adjacency-changes 
redistribute connected subnets 
passive-interface Ethernet3/0 
passive-interface Ethernet3/1 
network 10.18.18.18 0.0.0.0 area 200 
network 10.11.0.0 0.0.255.255 area 200 
network 10.12.0.0 0.0.255.255 area 200 
network 10.13.0.0 0.0.255.255 area 200 
! 
router bgp 200 
no bgp default ipv4-unicast 
bgp log-neighbor-changes 
timers bgp 10 30 
neighbor 10.16.16.16 remote-as 200 
neighbor 10.16.16.16 update-source Loopback0 
! 
address-family ipv4 
neighbor 10.16.16.16 activate 
neighbor 10.16.16.16 send-community extended 
no synchronization 
exit-address-family 
! 
address-family vpnv4 
neighbor 10.16.16.16 activate 
neighbor 10.16.16.16 send-community extended 
exit-address-family 
! 
address-family ipv4 vrf customersite 
neighbor 10.29.0.1 remote-as 300 
neighbor 10.29.0.1 activate 
neighbor 10.29.0.1 as-override 
neighbor 10.29.0.1 advertisement-interval 5 
neighbor 10.30.0.1 remote-as 300 
neighbor 10.30.0.1 activate 
neighbor 10.30.0.1 as-override 
neighbor 10.30.0.1 advertisement-interval 5 
no auto-summary 
no synchronization 
exit-address-family

CE2 (36K-38-4) Configuration

ip cef 
! 
interface Loopback0 
ip address 10.21.21.21 255.255.255.255 
! 
interface Ethernet1/3 
ip address 10.29.0.1 255.255.0.0 
! 
interface Ethernet5/0 
ip address 10.14.0.1 255.255.0.0 
! 
router ospf 300 
log-adjacency-changes 
redistribute connected subnets 
redistribute bgp 300 subnets 
passive-interface Ethernet1/3 
network 10.21.21.21 0.0.0.0 area 300 
network 10.14.0.0 0.0.255.255 area 300 
! 
router bgp 300 
no synchronization 
timers bgp 10 30 
redistribute connected 
redistribute ospf 300 match internal external 1 external 2 
neighbor 10.29.0.2 remote-as 200 
neighbor 10.29.0.2 advertisement-interval 5 
no auto-summary

CE3 (36K-38-5) Configuration

ip cef 
! 
interface Loopback0 
ip address 10.20.20.20 255.255.255.255 
no ip directed-broadcast 
! 
interface Ethernet0/2 
ip address 10.30.0.1 255.255.0.0 
no ip directed-broadcast 
! 
interface Ethernet0/3 
ip address 10.14.0.2 255.255.0.0 
no ip directed-broadcast 
! 
router ospf 300 
log-adjacency-changes 
redistribute connected subnets 
redistribute bgp 300 subnets 
passive-interface Ethernet0/2 
network 10.20.20.20 0.0.0.0 area 300 
network 10.14.0.0 0.0.255.255 area 300 
! 
router bgp 300 
no synchronization 
bgp log-neighbor-changes 
timers bgp 10 30 
redistribute connected 
redistribute ospf 300 match internal external 1 external 2 
neighbor 10.30.0.2 remote-as 200 
neighbor 10.30.0.2 advertisement-interval 5 
no auto-summary

Additional References

The following sections provide references related to MPLS VPNs.

Related Topic	Document Title
MPLS	MPLS Product Literature

Standards

Standard	Title
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.	--

MIBs

MIB	MIBs Link
No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified 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

MIB

MIBs Link

No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified 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 2547	BGP/MPLS VPNs

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/techsupport

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/techsupport

Feature Information for MPLS VPN CSC with LDP and IGP

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

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

Table 4

Feature Information for MPLS VPN CSC with LDP and IGP

Feature Name	Releases	Feature Configuration Information
MPLS VPN Carrier Supporting Carrier	12.0(14)ST 12.0(16)ST 12.2(8)T 12.0(21)ST 12.0(22)S 12.0(23)S	This feature enables you to set up and create an MPLS VPN CSC network that uses LDP to transport MPLS labels and an IGP to transport routes. In 12.0(14)ST, this feature was introduced. In 12.0(16)ST, this feature was integrated. In 12.2(8)T, this feature was integrated. In 12.0(21)ST, this feature was integrated. In 12.0(22)S, this feature was integrated. In 12.0(23)S, this feature was integrated. This feature uses no new or modified commands.

Feature Name

Releases

Feature Configuration Information

MPLS VPN Carrier Supporting Carrier

12.0(14)ST

12.0(16)ST

12.2(8)T

12.0(21)ST

12.0(22)S

12.0(23)S

This feature enables you to set up and create an MPLS VPN CSC network that uses LDP to transport MPLS labels and an IGP to transport routes.

In 12.0(14)ST, this feature was introduced.

In 12.0(16)ST, this feature was integrated.

In 12.2(8)T, this feature was integrated.

In 12.0(21)ST, this feature was integrated.

In 12.0(22)S, this feature was integrated.

In 12.0(23)S, this feature was integrated.

This feature uses no new or modified commands.

Glossary

ASBR -- Autonomous System Boundary router. A router that connects one autonomous system to another.

autonomous system --A collection of networks under a common administration sharing a common routing strategy.

BGP --Border Gateway Protocol. An interdomain routing protocol that exchanges network reachability information with other BGP systems (which may be within the same autonomous system or between multiple autonomous systems).

CE router--customer edge router. A router that is part of a customer network and that interfaces to a provider edge (PE) router. CE routers do not recognize associated MPLS VPNs.

CSC --Carrier Supporting Carrier. A hierarchical VPN model that allows small service providers, or customer carriers, to interconnect their IP or MPLS networks over an MPLS backbone. This eliminates the need for customer carriers to build and maintain their own MPLS backbone.

eBGP --external Border Gateway Protocol. A BGP between routers located within different autonomous systems. When two routers, located in different autonomous systems, are more than one hop away from one another, the eBGP session between the two routers is considered a multihop BGP.

edge router--A router that is at the edge of the network. It defines the boundary of the MPLS network. It receives and transmits packets. Also referred to as edge label switch router and label edge router.

iBGP --internal Border Gateway Protocol. A BGP between routers within the same autonomous system.

IGP --Interior Gateway Protocol. Internet protocol used to exchange routing information within a single autonomous system. Examples of common Internet IGP protocols include IGRP, OSPF, IS-IS, and RIP.

IP --Internet Protocol. Network layer protocol in the TCP/IP stack offering a connectionless internetwork service. IP provides features for addressing, type-of-service specification, fragmentation and reassembly, and security. Defined in RFC 791.

LDP --Label Distribution Protocol. A standard protocol between MPLS-enabled routers to negotiate the labels (addresses) used to forward packets.

LFIB --Label Forwarding Information Base. Data structure used in MPLS to hold information about incoming and outgoing labels and associated Forwarding Equivalence Class (FEC) packets.

MP-BGP --Multiprotocol BGP.

MPLS --Multiprotocol Label Switching. The name of the IETF working group responsible for label switching, and the name of the label switching approach it has standardized.

NLRI --Network Layer Reachability Information. The BGP sends routing update messages containing NLRI to describe a route and how to get there. In this context, an NLRI is a prefix. A BGP update message carries one or more NLRI prefixes and the attributes of a route for the NLRI prefixes; the route attributes include a BGP next hop gateway address and extended community values.

NSF --Nonstop forwarding enables routers to continuously forward IP packets following a Route Processor takeover or switchover to another Route Processor. NSF maintains and updates Layer 3 routing and forwarding information in the backup Route Processor to ensure that IP packets and routing protocol information are forwarded continuously during the switchover and route convergence process.

PE router--provider edge router. A router that is part of a service provider's network. It is connected to a customer edge (CE) router. All MPLS VPN processing occurs in the PE router.

QoS --quality of service. Measure of performance for a transmission system that indicates its transmission quality and service availability.

RD --route distinguisher. An 8-byte value that is concatenated with an IPv4 prefix to create a unique VPN-IPv4 prefix.

RT --route target. Extended community attribute used to identify the VRF routing table into which a prefix is imported.

SLA --Service Level Agreement given to VPN subscribers.

VPN --Virtual Private Network. A secure MPLS-based network that shares resources on one or more physical networks (typically implemented by one or more service providers). A VPN contains geographically dispersed sites that can communicate securely over a shared backbone network.

VRF --VPN routing and forwarding instance. Routing information that defines a VPN site that is attached to a PE router. A VRF consists of an IP routing table, a derived forwarding table, a set of interfaces that use the forwarding table, and a set of rules and routing protocols that determine what goes into the forwarding table.

Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)

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.

Bias-Free Language

Results

Chapter: MPLS VPN Carrier Supporting Carrier Using LDP and an IGP

MPLS VPN Carrier Supporting Carrier Using LDP and an IGP

Finding Feature Information

Prerequisites for MPLS VPN CSC with LDP and IGP

Restrictions for MPLS VPN CSC with LDP and IGP

Information About MPLS VPN CSC with LDP and IGP

MPLS VPN CSC Introduction

Benefits of Implementing MPLS VPN CSC

Benefits to the Backbone Carrier

Benefits to the Customer Carriers

Configuration Options for MPLS VPN CSC with LDP and IGP

Customer Carrier Is an ISP

Customer Carrier Is a BGP MPLS VPN Service Provider

How to Configure MPLS VPN CSC with LDP and IGP

Configuring the Backbone Carrier Core

Prerequisites

Verifying IP Connectivity and LDP Configuration in the CSC Core

Troubleshooting Tips

Configuring VRFs for CSC-PE Routers

Troubleshooting Tips

Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier

Troubleshooting Tips

Configuring the CSC-PE and CSC-CE Routers

Prerequisites

Configuring LDP on the CSC-PE and CSC-CE Routers

Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers

Verifying the Carrier Supporting Carrier Configuration

Configuration Examples for MPLS VPN CSC with LDP and IGP

MPLS VPN CSC Network with a Customer Who Is an ISP Example

CSC-CE1 Configuration

CSC-PE1 Configuration

CSC-PE2 Configuration

CSC-CE2 Configuration

MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider Example

CE1 Configuration

PE1 Configuration

CSC-CE1 Configuration

CSC-PE1 Configuration

CSC-PE2 Configuration

CSC-CE2 Configuration

PE2 Configuration

CE2 Configuration

MPLS VPN CSC Network That Contains Route Reflectors Example

Backbone Carrier Configuration

Route Reflector 1 (72K-37-1) Configuration

Route Reflector 2 (72K-38-1) Configuration

CSC-PE1 (75K-37-3) Configuration

CSC-PE2 (75K-38-3) Configuration

Customer Carrier Site 1 Configuration

PE1 (72K-36-8) Configuration

CSC-CE1 (72K-36-9) Configuration

PE2 (72K-36-7) Configuration

Route Reflector 3 (36K-38-4) Configuration

CE1 (36K-36-1) Configuration

Customer Carrier Site 2 Configuration

CSC-CE3 (72K-36-6) Configuration

PE3 (72K-36-4) Configuration

CSC-CE4 (72K-36-5) Configuration

Route Reflector 4 (36K-38-5) Configuration

CE2 (36K-36-2) Configuration

CE3 (36K-36-3) Configuration

MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example

Backbone Carrier Configuration

CSC-PE1 (72K-36-9) Configuration

P1 (75K-37-3) Configuration

P2 (75K-38-3) Configuration

CSC-PE2 (72K-36-5) Configuration

Customer Carrier Site 1 Configuration

CSC-CE1 (72K-36-8) Configuration

PE2 (72K-36-7) Configuration

CE1 (36K-36-1) Configuration

Customer Carrier Site 2 Configuration

CSC-CE2 (72K-36-4) Configuration

PE2 (72K-36-6) Configuration

CE2 (36K-38-4) Configuration

CE3 (36K-38-5) Configuration

Additional References