CCIE CCIE Service Provider 1

Question 1

In MPLS L3VPN, which protocol is used to distribute VPN labels and VPNv4 routes between PE routers?

Accepted Answer

MP-BGP

Answer

Multiprotocol BGP (MP-BGP) with the VPNv4 address family distributes customer routes and associated VPN labels between PE routers across the MPLS backbone.

Question 2

What is the purpose of a Route Distinguisher (RD) in MPLS L3VPN?

Accepted Answer

Making overlapping customer IP prefixes unique in the BGP table

Answer

An RD prepended to customer IPv4 prefixes creates unique VPNv4 routes, allowing BGP to differentiate between identical prefixes from different VPN customers.

Question 3

What mechanism in MPLS service provider networks controls which VPN routes are imported/exported between VRFs?

Accepted Answer

Route Target (RT) community

Answer

Route Targets are BGP extended communities used to control VPN route import and export between VRFs, determining which sites can communicate.

Question 4

In a service provider network, which IS-IS level is used for routing within a single area?

Accepted Answer

Level 1

Answer

IS-IS Level 1 routing handles intra-area routing within a single IS-IS area, analogous to OSPF intra-area routing.

Question 5

What is the function of RSVP-TE (Resource Reservation Protocol - Traffic Engineering) in MPLS networks?

Accepted Answer

Signaling LSPs with bandwidth reservations for traffic engineering

Answer

RSVP-TE signals explicitly-routed Label Switched Paths (LSPs) with bandwidth reservations, enabling traffic engineering in MPLS networks.

CCIE - Cisco Certified Internetwork Expert Practice Test

CCIE - Cisco Certified Internetwork Expert Practice Test

CCIE CCIE Service Provider 1