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The Cisco IOS XR address-family ipv4 labeled-unicast and the Cisco IOS/IOS XE neighbor send-label commands are used in which MPLS implementation?
A. Cisco MPLS TE
B. CSC using MP-BGP for label exchange
C. back-to-back VRF
D. AToM
E. VPLS
Correct Answer: B
Explanation/Reference:
Explanation:
Explanation:
http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/fscscleb.pdf
The MPLS VPN–Carrier Supporting Carrier–IPv4 BGP Label Distribution feature lets you 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 using multiple paths. 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:
. BGP takes the place of an IGP and LDP in a Virtual Private Network (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. . BGP is the preferred routing protocol for connecting two Internet service providers (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.
