Layer 3 VPN Concepts and Architecture JN0-664 Practice Questions (Page 1)

Questions 1–5

1. 1foundation · easy

   Which Layer 3 VPN topology is best suited for a hub-and-spoke model where all traffic between spoke sites must pass through a central site for security inspection?

   • AHub-and-spoke topology
   • BPoint-to-point topology
   • CFull-mesh topology
   • DExtranet topology
   Reveal Solution Discussion Select an answer first
2. 2foundation · easy

   What is the primary purpose of a route distinguisher (RD) in a Layer 3 VPN?

   • ATo make customer IPv4 prefixes unique across the provider's BGP table.
   • BTo control which routes are imported into a VRF.
   • CTo specify the MPLS label used for forwarding VPN traffic.
   • DTo identify the next-hop PE router for a VPN route.
   Reveal Solution Discussion Select an answer first
4. 3expert · hard

   A service provider is troubleshooting a Layer 3 VPN issue where a customer site cannot reach a remote site. The engineer checks the MP-BGP session between the two PE routers and confirms it is established. The VRF on the local PE has the route to the remote site's prefix, but the next hop is unreachable. What is the most likely cause?

   • AThe MPLS label advertised by the remote PE for the route is invalid
   • BThe route target on the remote PE's VRF does not match the local PE's import policy
   • CThe IGP route to the BGP next hop (the remote PE's loopback) is not present in the global routing table
   • DThe route distinguisher on the remote PE is not unique, causing the route to be rejected
   Reveal Solution Discussion Select an answer first
5. 4foundation · easy

   How does a VRF provide separate routing for each VPN on a PE router?

   • ABy using a different routing protocol for each VPN.
   • BBy using a different BGP session for each VPN.
   • CBy maintaining a separate routing and forwarding table for each VPN, with interfaces assigned to the VRF.
   • DBy using a different MPLS label for each VPN.
   Reveal Solution Discussion Select an answer first
6. 5expert · medium

   A service provider is implementing a Layer 3 VPN for a customer with multiple sites. The customer requires that all sites can communicate with each other, but the provider wants to minimize the number of route targets used. Which configuration approach achieves this with the fewest route targets?

   • AUse a route target per site pair, where each pair of sites has a unique route target
   • BUse two route targets, one for export and one for import, on all sites
   • CUse a unique route target for each site, where each site imports all other sites' route targets
   • DUse a single route target for all sites, where each site's VRF exports and imports that same route target
   Reveal Solution Discussion Select an answer first