300-420 Question 193
Single answerAn enterprise organization is planning to implement MPLS Layer 3 VPN to connect its branch offices to the central data center. The IT team has identified the need for route isolation between different branches while ensuring that all branches can access shared services hosted in the data center. Which approach should the organization take to achieve this requirement?
- A
Configure unique VRFs for each branch and use route targets to import/export shared services routes.
- B
Use a single shared VRF for all branches and the data center to simplify routing.
- C
Implement MPLS Layer 2 VPN instead of Layer 3 VPN to achieve route isolation.
- D
Configure static routes on all PE routers to interconnect branch offices and the data center.
Show answer and explanation
Correct answer: A
Explanation
MPLS Layer 3 VPN uses Virtual Routing and Forwarding (VRF) instances to isolate routing information between different customers or sites. By assigning unique VRFs to each branch and using route targets, the organization can control route import/export policies to ensure isolation while selectively connecting shared services hosted in the data center. This approach is scalable and aligns with MPLS Layer 3 VPN best practices.
- A. Correct.
Configuring unique VRFs for each branch ensures route isolation, and using route targets to import/export shared services routes provides selective connectivity to the data center. This is the correct approach for meeting the requirements.
- B. Incorrect.
Using a single shared VRF would not provide the necessary route isolation between branches, violating the requirement.
- C. Incorrect.
MPLS Layer 2 VPN does not inherently provide the Layer 3 route isolation or granularity required for branch-to-data center connectivity in this scenario.
- D. Incorrect.
Static routes are not scalable or efficient for managing dynamic, multi-branch environments, especially in MPLS Layer 3 VPN designs.