300-420 Question 190
Single answerA company is expanding its network to connect two geographically dispersed sites with a Layer 2 VPN solution. The sites need to appear as if they are on the same Layer 2 domain to support their existing VLAN-based applications. As the network designer, you need to choose the most appropriate Layer 2 VPN technology that offers flexibility and scalability. Which technology would you recommend?
- A
Ethernet over MPLS (EoMPLS)
- B
Virtual Private LAN Service (VPLS)
- C
Point-to-Point GRE Tunnels
- D
IPsec VPN with VLAN Tagging
Show answer and explanation
Correct answer: B
Explanation
Virtual Private LAN Service (VPLS) is the appropriate choice for this scenario because it is specifically designed to extend Layer 2 domains across geographically dispersed sites, offering multipoint-to-multipoint connectivity. This makes it ideal for supporting VLAN-based applications while providing flexibility and scalability.
- A. Incorrect.
Ethernet over MPLS (EoMPLS) is a suitable choice for point-to-point Layer 2 VPN connections, but it does not support multipoint-to-multipoint connectivity required for a flexible and scalable solution.
- B. Correct.
Virtual Private LAN Service (VPLS) is a Layer 2 VPN technology that provides multipoint-to-multipoint connectivity, making geographically dispersed sites appear as if they are on the same Layer 2 domain. This aligns with the company's requirements for flexibility and scalability.
- C. Incorrect.
Point-to-Point GRE Tunnels are primarily used for Layer 3 connectivity and do not provide Layer 2 VPN functionality needed to connect VLANs across the sites.
- D. Incorrect.
IPsec VPN with VLAN Tagging is a Layer 3 VPN solution and does not inherently support Layer 2 VPN requirements, such as making multiple sites appear on the same Layer 2 domain.