MPLS Layer 3 VPNs Configuration Guide, Cisco IOS XE Release 2

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Book Title

MPLS Layer 3 VPNs Configuration Guide, Cisco IOS XE Release 2

Chapter Title

Multi VRF Selection Using Policy-Based Routing

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Updated:
November 30, 2011

Chapter: Multi VRF Selection Using Policy-Based Routing

Multi-VRF Selection Using Policy-Based Routing

Last Updated: December 15, 2011

The Multi-VRF Selection Using Policy-Based Routing (PBR) feature allows a specified interface on a provider edge (PE) router to route packets to Virtual Private Networks (VPNs) based on packet length or match criteria defined in an IP access list.

You can enable VPN routing and forwarding (VRF) selection by policy routing packets through a route map, through the global routing table, or to a specified VRF.

You can enable policy-routing packets for VRF instances by using route map commands with set commands.

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 Multi-VRF Selection Using Policy-Based Routing

  • The router must support policy-based routing (PBR) in order for you to configure this feature.
  • A VRF must be defined before you configure this feature. An error message is displayed on the console if no VRF exists.

Restrictions for Multi-VRF Selection Using Policy-Based Routing

  • All commands that aid in routing also support hardware switching, except for the set ip next-hop verify availability command because Cisco Discovery Protocol information is not available in the line cards.
  • Protocol Independent Multicast (PIM) and multicast packets do not support PBR and cannot be configured for a source IP address that is a match criterion for this feature.
  • The set vrf and set ip global next-hop commands can be configured with the set default interface, set interface , set ip default next-hop, and set ip next-hop commands. But the set vrf and set ip global next-hop commands take precedence over the set default interface, set interface , set ip default next-hop, and set ip next-hop commands. No error message is displayed if you attempt to configure the set vrf command with any of these three set commands.
  • The Multi-VRF Selection Using Policy-Based Routing (PBR) feature cannot be configured with IP prefix lists.
  • The set global and set vrf commands cannot be simultaneously applied to a route map.
  • The Multi-VRF Selection Using Policy-Based Routing (PBR) feature supports VRF-lite; that is, only IP routing protocols run on the router. Multiprotocol Label Switching (MPLS) and VPN cannot be configured.

Information About Multi-VRF Selection Using Policy-Based Routing

Policy Routing of VPN Traffic Based on Match Criteria

The Multi-VRF Selection Using Policy-Based Routing feature is an extension of the VRF Selection Based on Source IP Address feature. The PBR implementation of the VRF selection feature allows you to policy route VPN traffic based on match criteria. Match criteria are defined in an IP access list and/or are based on packet length. The following match criteria are supported in Ciscosoftware:

  • IP access lists--Define match criteria based on IP addresses, IP address ranges, and other IP packet access list filtering options. Named, numbered, standard, and extended access lists are supported. All IP access list configuration options in Cisco software can be used to define match criteria.
  • Packet lengths--Define match criteria based on the length of a packet, in bytes. The packet length filter is defined in a route map with the match length route-map configuration command.

Policy routing is defined in the route map. The route map is applied to the incoming interface with the ip policy route-map interface configuration command. An IP access list is applied to the route map with the match ip address route-map configuration command. Packet length match criteria are applied to the route map with the match length route-map configuration command. The set action is defined with the set vrf route-map configuration command. The match criteria are evaluated, and the appropriate VRF is selected by the set command. This combination allows you to define match criteria for incoming VPN traffic and policy route VPN packets out to the appropriate VRF.

Policy-Based Routing set Commands

Policy-routing Packets for VRF Instances

To enable policy-routing packets for VRF instances, you can use route map commands with the following set commands. They are listed in the order in which the router uses them during the routing of packets.

  • set TOS--Sets the Type of Service (TOS) bits in the header of an IP packet.
  • set DF--Sets the Don't Fragment (DF) bit in the header of an IP packet.
  • set vrf--Routes packets through the specified interface. The interface can belong to the global routing table or to any other VRF instance.
  • set global--Routes packets through the global routing table. This command is useful for routing ingress packets belonging to a specific VRF through the global routing table.
  • set ip vrf next-hop--Indicates where to output packets that pass a match criteria of a route map for policy routing when the next hop must be under a specified VRF.
  • set ip global next-hop--Indicates where to forward packets that pass a match criterion of a route map for policy routing and for which the Cisco IOS XE software uses the global routing table.
  • set interface--When packets enter a VRF, routes the packets out of the egress interface under the same VRF according to the set interface policy, provided that the Layer 2 rewrite information is available.
  • set ip default vrf--Provides inherit-VRF and inter-VRF routing. With inherit-VRF routing, packets arriving at a VRF interface are routed by the same outgoing VRF interface. With inter-VRF routing, packets arriving at a VRF interface are routed via any other outgoing VRF interface.
  • set ip default global--Provides VRF to global routing.
  • set default interface--Indicates where to output packets that pass a match criterion of a route map for policy routing and have no explicit route to the destination. The interface can belong to any VRF.
  • set ip global next-hop--Routes packets through the global routing table, where the next hop lookup will be in the global routing table.
  • set ip default next-hop--Indicates where to output packets that pass a match criterion of a route map for policy routing and for which the Cisco IOS XE software has no explicit route to a destination.
  • set ip precedence--Sets the IP precedence bit in the header of an IP packet.

Change of Normal Routing and Forwarding Behavior

When you configure PBR, you can use the following four set commands to change normal routing and forwarding behavior. Configuring any of these set commands overrides the routing behavior of packets entering the interface if the packets do not belong to a VRF. The packets are routed from the egress interface across the global routing table.

  • set default interface--Indicates where to output packets that pass a match criterion of a route map for policy routing and have no explicit route to the destination.
  • set interface--When packets enter a VRF, routes the packets out of the egress interface under the same VRF according to the set interface policy, provided that the Layer 2 rewrite information is available.

Note
The interface must be a peer-to-peer (P2P) interface.
  • set ip default next-hop--Indicates where to output packets that pass a match criterion of a route map for policy routing and for which the Cisco IOS XE software has no explicit route to a destination.
  • set ip next-hop--Indicates where to output packets that pass a match criterion of a route map for policy routing.

Support of Inherit-VRF Inter-VRF and VRF-to-Global Routing

The Multi-VRF Selection Using Policy-Based Routing (PBR) feature supports inherit-VRF and inter-VRF. With inherit-VRF routing, packets arriving at a VRF interface are routed by the same outgoing VRF interface. With inter-VRF routing, packets arriving at a VRF interface are routed via any other outgoing VRF interface.

VRF-to-global routing causes packets that enter any VRF interface to be routed via the global routing table. When a packet arrives on a VRF interface, the destination lookup normally is done only in the corresponding VRF table. If a packet arrives on a global interface, the destination lookup is done in the global routing table.

The Multi-VRF Selection Using Policy-Based Routing (PBR) feature modifies the following set commands to support inherit-VRF, inter-VRF, and VRF-to-global routing. The commands are listed in the order in which the router uses them during the routing of packets.

  • set global--Routes packets through the global routing table. This command is useful for routing ingress packets belonging to a specific VRF through the global routing table.
  • set ip global next-hop--Indicates where to forward packets that pass a match criterion of a route map for policy routing and for which the Cisco software uses the global routing table.
  • set ip vrf next-hop--Causes the router to look up the next hop in the VRF table. If a packet arrives on an interface that belongs to a VRF and the packet needs to be routed via a different VRF, you can use the set ip vrf next-hop command.
  • set ip default vrf--Provides inherit-VRF and inter-VRF routing. With inherit-VRF routing, packets arriving at a VRF interface are routed by the same outgoing VRF interface. With inter-VRF routing, packets arriving at a VRF interface are routed via any other outgoing VRF interface.
  • set interface--When packets enter a VRF, routes the packets out of the egress interface under the same VRF, according to the set interface policy, provided that the Layer 2 rewrite information is available.
  • set default interface--Indicates where to output packets that pass a match criterion of a route map for policy routing and have no explicit route to the destination. The interface can belong to any VRF.
  • set ip next-hop--Routes packets through the global routing table in an IP-to-IP routing and forwarding environment.
  • set vrf--Selects the appropriate VRF after a successful match occurs in the route map. VRS-aware PSV allows only inter-VRF (or VRF-to-VRF) switching.

How to Configure Multi-VRF Selection Using Policy-Based Routing

Defining the Match Criteria for Multi-VRF Selection Using PBR

Define the match criteria for multi-VRF selection using PBR so that you can selectively route the packets instead of using their default routing and forwarding.

The match criteria for multi-VRF selection using PBR are defined in an access list. Standard, named, and extended access lists are supported.

You can define the match criteria based on the packet length by configuring the match length route-map configuration command. This configuration option is defined entirely within a route map.

The following sections explain how to configure PBR route selection:

Configuring Multi-VRF Selection Using PBR with a Standard Access List

Before You Begin

The tasks in the following sections assume that the VRF and associated IP address are already defined.


SUMMARY STEPS

1.    enable

2.    configure terminal

3.    access-list access-list-number {deny | permit} [source source-wildcard] [log]


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
access-list access-list-number {deny | permit} [source source-wildcard] [log]


Example:

Router(config)# access-list 40 permit source 10.1.1.0/24 0.0.0.255

 

Creates an access list and defines the match criteria for the route map.

  • Match criteria can be defined based on IP addresses, IP address ranges, and other IP packet access list filtering options. Named, numbered, standard, and extended access lists are supported. You can use all IP access list configuration options to define match criteria.
  • The example creates a standard access list numbered 40. This filter permits traffic from any host with an IP address in the 10.1.1.0/24 subnet.
 

Configuring Multi-VRF Selection Using PBR with a Named Extended Access List

To configure Multi-VRF Selection using PBR with a named extended access list, complete the following steps.

Before You Begin

The tasks in the following sections assume that the VRF and associated IP address are already defined.


SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip access-list {standard | extended} [access-list-name | access-list-number]

4.    [sequence-number] {permit | deny} protocol source source-wildcard destination destination-wildcard [option option-value] [precedence precedence] [tostos] [ttl operator-vaue] [log] [time-range time-range-name] [fragments]


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 access-list {standard | extended} [access-list-name | access-list-number]


Example:

Router(config)# ip access-list extended NAMEDACL

 

Specifies the IP access list type and enters the corresponding access list configuration mode.

  • You can specify a standard, extended, or named access list.
 
Step 4
[sequence-number] {permit | deny} protocol source source-wildcard destination destination-wildcard [option option-value] [precedence precedence] [tostos] [ttl operator-vaue] [log] [time-range time-range-name] [fragments]


Example:

Router(config-ext-nacl)# permit ip any any option any-options

 

Defines the criteria for which the access list will permit or deny packets.

  • Match criteria can be defined based on IP addresses, IP address ranges, and other IP packet access list filtering options. Named, numbered, standard, and extended access lists are supported. You can use all IP access list configuration options to define match criteria.
  • The example creates a named access list that permits any configured IP option.
 

Configuring Multi-VRF Selection in a Route Map

Incoming packets are filtered through the match criteria that are defined in the route map. After a successful match occurs, the set vrf command configuration determines the VRF through which the outbound VPN packets will be policy routed.

Before You Begin

You must define the VRF before you configure the route map; otherwise an error message appears on the console.

A receive entry must be added to the VRF selection table with the ip vrf receive command. If a match and set operation occurs in the route map but there is no receive entry in the local VRF table, the packet will be dropped if the packet destination is local.


SUMMARY STEPS

1.    enable

2.    configure terminal

3.    route-map map-tag [permit | deny] [sequence-number]

4.   Do one of the following:

  • set ip vrf vrf-name next-hop ip-address [...ip-address]
  • or
  • set ip next-hop recursive vrf ip-address [...ip-address]
  • or
  • set ip global next-hop ip-address [...ip-address]

5.   Do one of the following:

  • match ip address {acl-number [acl-name | acl-number]}
  • or
  • match length minimum-lengthmaximum-length

6.    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
route-map map-tag [permit | deny] [sequence-number]


Example:

Router(config)# route-map map1 permit 10

 

Defines the conditions for redistributing routes from one routing protocol into another, or enables policy routing.

  • Enters route-map configuration mode.
 
Step 4
Do one of the following:
  • set ip vrf vrf-name next-hop ip-address [...ip-address]
  • or
  • set ip next-hop recursive vrf ip-address [...ip-address]
  • or
  • set ip global next-hop ip-address [...ip-address]


Example:

Router(config-route-map)# set ip vrf myvrf next-hop 10.0.0.0



Example:

Router(config-route-map)# set ip next-hop recursive vrf 10.0.0.0



Example:

Router(config-route-map)# set ip global next-hop 10.0.0.0

 

Indicates where to forward packets that pass a match criterion of a route map for policy routing when the next hop must be under a specified VRF.

or

Indicates which destination or next hop will be used for packets that pass the match criterion configured in the route map.

or

Indicates where to forward packets that pass a match criterion of a route map for policy routing and for which the software uses the global routing table.

 
Step 5
Do one of the following:
  • match ip address {acl-number [acl-name | acl-number]}
  • or
  • match length minimum-lengthmaximum-length


Example:

Router(config-route-map)# match ip address 1 or



Example:

Router(config-route-map)# match length 3 200

 

Distributes any routes that have a destination network number address that is permitted by a standard or extended access list, and performs policy routing on matched packets. IP access lists are supported.

  • The example configures the route map to use standard access list 1 to define match criteria.

or

Specifies the Layer 3 packet length in the IP header as a match criterion in a class map.

  • The example configures the route map to match packets that are 3 to 200 bytes in length.
 
Step 6
end


Example:

Router(config-route-map)# end

 

Exits route-map configuration mode and returns to privileged EXEC mode.

 

Configuring Multi-VRF Selection Using PBR and IP VRF Receive on the Interface

The route map is attached to the incoming interface with the ip policy route-map interface configuration command.

The source IP address must be added to the VRF selection table. VRF selection is a one-way (unidirectional) feature. It is applied to the incoming interface. If a match and set operation occurs in the route map but there is no receive entry in the local VRF table, the packet is dropped if the packet destination is local.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface type number [name-tag]

4.    ip policy route-map map-tag

5.    ip vrf receive vrf-name

6.    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
interface type number [name-tag]


Example:

Router(config)# interface FastEthernet 0/1/0

 

Configures an interface and enters interface configuration mode.

 
Step 4
ip policy route-map map-tag


Example:

Router(config-if)# ip policy route-map map1

 

Identifies a route map to use for policy routing on an interface.

  • The configuration example attaches the route map named map1 to the interface.
 
Step 5
ip vrf receive vrf-name


Example:

Router(config-if)# ip vrf receive VRF-1

 

Adds the IP addresses that are associated with an interface into the VRF table.

  • This command must be configured for each VRF that will be used for VRF selection.
 
Step 6
end


Example:

Router(config-if)# end

 

Exits interface configuration mode and returns to privileged EXEC mode.

 

Verifying the Configuration of Multi-VRF Selection Using PBR

To verify the configuration of the Multi-VRF Selection Using Policy-Based Routing (PBR) feature, perform the following steps. You can enter the commands in any order.

SUMMARY STEPS

1.    show ip access-list [access-list-number | access-list-name]

2.    show route-map [map-name]

3.    show ip policy


DETAILED STEPS
Step 1   show ip access-list [access-list-number | access-list-name]

To verify the configuration of match criteria for PBR multi-VRF selection, use the show ip access-list command. The following show ip access-list command output displays three subnet ranges defined as match criteria in three standard access lists:



Example: 
Router# show ip access-list
 
Standard IP access list 40
 10 permit 10.1.0.0, wildcard bits 0.0.255.255
Standard IP access list 50
 10 permit 10.2.0.0, wildcard bits 0.0.255.255
Standard IP access list 60
 10 permit 10.3.0.0, wildcard bits 0.0.255.255
Step 2   show route-map [map-name]

Use this command to verify match and set commands within the route map:



Example: 
Router# show route-map

To verify the route-map configuration, use the show route-map command. The output displays the match criteria and set action for each route-map sequence. The output also displays the number of packets and bytes that have been policy routed per each route-map sequence.



Example: 
Router# show route-map map1 
route-map map1, permit, sequence 10
Match clauses:
Set clauses:
 ip next-hop vrf myvrf 10.5.5.5  10.6.6.6  10.7.7.7
 ip next-hop global 10.8.8.8  10.9.9.9
Policy routing matches: 0 packets, 0 bytes
Router# show route-map map2 
route-map map2, permit, sequence 10
Match clauses:
Set clauses:
 vrf myvrf 
Policy routing matches: 0 packets, 0 bytes
Router# show route-map map3 
route-map map3, permit, sequence 10
Match clauses:
Set clauses:
 global
Policy routing matches: 0 packets, 0 bytes

The following show route-map command displays output from the set ip vrf next-hop command:



Example: 
Router(config)# route-map test
 
Router(config-route-map)# set ip vrf myvrf next-hop 
Router(config-route-map)# set ip vrf myvrf next-hop 192.168.3.2
Router(config-route-map)# match ip address 255 101
Router(config-route-map)# end
Router# show route-map
 
route-map test, permit, sequence 10
 Match clauses:
  ip address (access-lists): 101
 Set clauses:
  ip vrf myvrf next-hop 192.168.3.2
 Policy routing matches: 0 packets, 0 bytes

The following show route-map command displays output from the set ip global command:



Example: 
Router(config)# route-map test
Router(config-route-map)# match ip address 255 101
Router(config-route-map)# set ip global next-hop 192.168.4.2 
Router(config-route-map)# end
Router# show route-map
 
*May 25 13:45:55.551: %SYS-5-CONFIG_I: Configured from console by consoleout-map
route-map test, permit, sequence 10
 Match clauses:
  ip address (access-lists): 101
 Set clauses:
  ip global next-hop 192.168.4.2
 Policy routing matches: 0 packets, 0 bytes
Step 3   show ip policy

To verify the PBR multi-VRF selection policy, use the show ip policy command:



Example: 
Router# show ip policy

The following show ip policy command output displays the interface and associated route map that is configured for policy routing:



Example: 
Router# show ip policy 
Interface                Route map
FastEthernet0/1/0        PBR-VRF-Selection

Configuration Examples for Multi-VRF Selection Using Policy-Based Routing

Defining the Match Criteria for Multi-VRF Selection Using PBR Example

In the following example, three standard access lists are created to define match criteria for three different subnetworks. Any packets received on FastEthernet interface 0/1/0 will be policy routed through the PBR-VRF-Selection route map to the VRF that is matched in the same route-map sequence. If the source IP address of the packet is part of the 10.1.0.0/24 subnet, VRF1 will be used for routing and forwarding. 

access-list 40 permit source 10.1.0.0 0.0.255.255
access-list 50 permit source 10.2.0.0 0.0.255.255
access-list 60 permit source 10.3.0.0 0.0.255.255
route-map PBR-VRF-Selection permit 10
 match ip address 40
 set vrf VRF1
 !
route-map PBR-VRF-Selection permit 20
 match ip address 50
 set vrf VRF2
 !
route-map PBR-VRF-Selection permit 30
 match ip address 60
 set vrf VRF3
 !
interface FastEthernet 0/1/0
 ip address 192.168.1.6 255.255.255.252
 ip vrf forwarding VRF4 
 ip policy route-map PBR-VRF-Selection
 ip vrf receive VRF1
 ip vrf receive VRF2
 ip vrf receive VRF3

Configuring Multi-VRF Selection in a Route Map Example

The following example shows a set ip vrf next-hop command that applies policy-based routing to the VRF interface named myvrf and specifies that the IP address of the next hop is 10.0.0.2: 

Router(config)# route-map map1 permit
Router(config)# set vrf myvrf
Router(config-route-map)# set ip vrf myvrf next-hop 10.0.0.2
Router(config-route-map)# match ip address 101
Router(config-route-map)# end

The following example shows a set ip global command that specifies that the router should use the next hop address 10.0.0.1 in the global routing table: 

Router(config-route-map)# set ip global next-hop 10.0.0.1

Additional References

Related Documents

Related Topic

Document Title

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

Cisco IOS Multiprotocol Label Switching Command Reference

IP access list commands

Cisco IOS Security Command Reference

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

RFCs

RFC

Title

No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.

--

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

Feature Information for Multi-VRF Selection Using Policy-Based Routing

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

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

Table 1 Feature Information for Multi-VRF Selection Using Policy-Based Routing

Feature Name

Releases

Feature Information

Multi-VRF Selection Using Policy-Based Routing (PBR)

Cisco IOS XE Release 2.2

The Multi-VRF Selection Using Policy-Based Routing (PBR) feature allows a specified interface on a provider edge (PE) router to route packets to VPNs based on packet length or match criteria defined in an IP access list. This feature and the VRF Selection Based on Source IP Address feature can be configured together on the same interface.

In Cisco IOS XE Release 2.2, this feature was introduced on the Cisco ASR 1000 Series Aggregation Services Routers.

The following commands were modified: set ip global, set ip vrf next-hop, and set vrf.

Glossary

CE router--customer edge router. A router that is part of a customer network and that interfaces to a provider edge (PE) router.

Inherit-VRF routing--Packets arriving at a VRF interface are routed by the same outgoing VRF interface.

Inter-VRF routing--Packets arriving at a VRF interface are routed via any other outgoing VRF interface.

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.

PBR --policy-based routing. PBR allows a user to manually configure how received packets should be routed.

PE router--provider edge router. A router that is part of a service provider's network and that is connected to a CE router. It exchanges routing information with CE devices by using static routing or a routing protocol such as BGP, RIPv1, or RIPv2.

VPN --Virtual Private Network. A collection of sites sharing a common routing table. A VPN provides a secure way for customers to share bandwidth over an ISP backbone network.

VRF --A VPN routing and forwarding instance. 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.

VRF-lite --A feature that enables a service provider to support two or more VPNs, where IP addresses can be overlapped among the VPNs.

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.

© 2011 Cisco Systems, Inc. All rights reserved.

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