300-420 Question 159
Single answerA service provider is designing a Layer 2 VPN solution for a large enterprise customer that requires secure and scalable connectivity between multiple branch locations. The solution must provide end-to-end transparency for VLAN tags and ensure MAC address table isolation between customers. Which Layer 2 VPN technology should the service provider implement?
- A
Point-to-Point Protocol (PPP)
- B
Virtual Private LAN Service (VPLS)
- C
EoMPLS (Ethernet over MPLS)
- D
GRE Tunneling
Show answer and explanation
Correct answer: C
Explanation
EoMPLS (Ethernet over MPLS) is the best solution for this scenario because it is specifically designed to provide point-to-point Layer 2 VPN connectivity with VLAN tag transparency and MAC address table isolation. This makes it ideal for enterprise customers requiring secure and scalable Ethernet connectivity between branch locations. Other options either belong to different protocol layers or do not meet the requirements for Layer 2 VPN functionality.
- A. Incorrect.
Point-to-Point Protocol (PPP) is not a Layer 2 VPN technology for Ethernet traffic. It is used for point-to-point communication over serial links and does not support VLAN transparency or MAC isolation.
- B. Incorrect.
Virtual Private LAN Service (VPLS) is a Layer 2 VPN technology designed for multi-point Ethernet services. However, it is more complex to implement and may not be the best fit for scenarios focusing on point-to-point connectivity with VLAN transparency.
- C. Correct.
EoMPLS (Ethernet over MPLS) is the correct choice. It provides point-to-point Layer 2 VPN services, maintains VLAN tag transparency, and isolates MAC address tables between customers. It is widely used for simple and scalable Layer 2 VPN solutions.
- D. Incorrect.
GRE Tunneling is a Layer 3 tunneling protocol and does not offer the Layer 2 features like VLAN transparency or MAC address table isolation required in this scenario.