Cisco Cisco IOS Software Release 12.2(14)SX
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Cisco IOS Release 12.2(14)S
MPLS VPN—Carrier Supporting Carrier—IPv4
BGP Label Distribution
BGP Label Distribution
This feature enables you to configure your carrier supporting carrier network to enable Border Gateway
Protocol (BGP) to transport routes and Multiprotocol Label Switching (MPLS) labels between the
backbone carrier provider edge (PE) routers and the customer carrier customer edge (CE) routers.
Previously you had to use Label Distribution Protocol (LDP) to carry the labels and an Internal Gateway
Protocol (IGP) to carry the routes between PE and CE routers to achieve the same goal.
Protocol (BGP) to transport routes and Multiprotocol Label Switching (MPLS) labels between the
backbone carrier provider edge (PE) routers and the customer carrier customer edge (CE) routers.
Previously you had to use Label Distribution Protocol (LDP) to carry the labels and an Internal Gateway
Protocol (IGP) to carry the routes between PE and CE routers to achieve the same goal.
The benefits of using BGP to distribute IPv4 routes and MPLS label routes are that:
•
BGP takes the place of an IGP and LDP in a VPN forwarding/routing instance (VRF) table. You can
use BGP to distribute routes and MPLS labels. Using a single protocol instead of two simplifies the
configuration and troubleshooting.
use BGP to distribute routes and MPLS labels. Using a single protocol instead of two simplifies the
configuration and troubleshooting.
•
BGP is the preferred routing protocol for connecting two ISPs, mainly because of its routing policies
and ability to scale. ISPs commonly use BGP between two providers. This feature enables those
ISPs to use BGP.
and ability to scale. ISPs commonly use BGP between two providers. This feature enables those
ISPs to use BGP.
This feature is an extension of the Carrier Supporting Carrier feature, introduced in Release 12.0(14)ST,
which was based on LDP.
which was based on LDP.
Feature Specifications for MPLS VPN—Carrier Supporting Carrier—IPv4 BGP Label Distribution
Feature History
Release
Modification
12.0(21)ST
This feature was introduced.
12.0(22)S
This feature was implemented on the Cisco 12000 series router (see
for the line cards supported) and integrated into Cisco IOS
Release 12.0(22)S.
Release 12.0(22)S.
12.0(23)S
Support was added for the Cisco 12000 Series Eight-Port OC-3c/STM-1c
ATM Line Card (8-Port OC-3 ATM) and the Cisco 12000 Series Three-Port
Gigabit Ethernet Line Card (3-Port GbE).
ATM Line Card (8-Port OC-3 ATM) and the Cisco 12000 Series Three-Port
Gigabit Ethernet Line Card (3-Port GbE).
12.2(13)T
This feature was integrated into Cisco IOS Release 12.2(13)T.
12.0(24)S
Support was added for the Cisco 12000 Series One-Port 10-Gigabit
Ethernet Line Card (1-Port 10-GbE) and the Cisco 12000 Series Modular
Gigabit Ethernet/ Fast Ethernet Line Card (Modular GbE/FE) and
implemented on Cisco IOS 12.0(24)S.
Ethernet Line Card (1-Port 10-GbE) and the Cisco 12000 Series Modular
Gigabit Ethernet/ Fast Ethernet Line Card (Modular GbE/FE) and
implemented on Cisco IOS 12.0(24)S.
12.2(14)S
This feature was integrated into Cisco IOS Release 12.2(14)S and
implemented on Cisco 7200 and Cisco 7500 series routers.
implemented on Cisco 7200 and Cisco 7500 series routers.