Unified MPLS Benefits and True Statements

BD.

Unified MPLS is a technology that extends the capabilities of MPLS (Multiprotocol Label Switching) to support inter-AS (Autonomous System) and inter-provider VPN (Virtual Private Network) services. It also enables the creation of seamless MPLS-based networks that span multiple domains, including different service providers, while maintaining scalability and simplicity.

A. Unified MPLS works on Cisco IOS XR Software only. This statement is incorrect. Unified MPLS is a technology that is not limited to any particular vendor or software. It is based on standardized protocols such as MPLS, LDP (Label Distribution Protocol), IGP (Interior Gateway Protocol), and BGP (Border Gateway Protocol) and can be implemented on any platform that supports them.

B. Unified MPLS extends MPLS across multidomain networks in a scalable manner. This statement is correct. Unified MPLS enables the creation of seamless MPLS-based networks that span multiple domains, including different service providers. It uses advanced techniques such as seamless MPLS (S-MPLS), which provides a way to extend MPLS labels across multiple administrative domains, and hierarchical VPLS (Virtual Private LAN Service), which allows service providers to offer VPLS services to their customers while maintaining scalability and simplicity.

C. New technologies or protocols are not used; only MPLS, LDP, IGP, and BGP are used. This statement is partially correct. Unified MPLS is based on standard protocols such as MPLS, LDP, IGP, and BGP, but it also incorporates advanced techniques such as S-MPLS and hierarchical VPLS to enable the creation of seamless MPLS-based networks that span multiple domains.

D. ABR loopback prefixes should always be redistributed from the core IGP into the aggregation IGP. This statement is not related to Unified MPLS and is incorrect in the context of the question.

E. The RRs are part of the control path only. This statement is partially correct. RRs (Route Reflectors) are used in the control plane of MPLS networks to reduce the number of BGP peering sessions required to distribute VPN routing information among the provider edge routers (PEs). In the context of Unified MPLS, RRs are used to distribute VPN routing information across multiple domains and providers, making them part of the control path.