When EVPN serves as the control plane to carry L3VPN or L2VPN services, which of the following types of tunnels can be combined with the data forwarding plane? (Multiple choice)

Question

Options

• ASR-MPLS
• BQinQ
• CSRv6
• DVXLAN

• A
  81% (21)
• B
  19% (5)

Explanation

EVPN (Ethernet VPN) is a BGP-based control plane that is deliberately decoupled from the data forwarding plane, making it technology-agnostic - it can signal MAC/IP reachability and VPN membership regardless of how packets are physically encapsulated and forwarded across the network. SR-MPLS (A), SRv6 (C), and VXLAN (D) are all recognized data plane tunnel technologies that EVPN can pair with: SR-MPLS and SRv6 are Segment Routing variants used widely in service provider cores, while VXLAN is the dominant choice in data center fabrics - all three can receive EVPN-signaled forwarding state and encapsulate L2/L3 traffic accordingly.

QinQ (B) is incorrect because it is a Layer 2 VLAN-stacking mechanism (IEEE 802.1ad), not a tunnel technology in this context. QinQ operates at the access/aggregation layer to extend customer VLANs over a provider network, but it does not provide the IP-based or label-based encapsulation that EVPN needs to carry VPN services across a routed underlay.

Memory tip: Think "tunnel = packet-in-packet across a routed network." SR-MPLS, SRv6, and VXLAN all wrap original traffic inside a new header to traverse an IP/MPLS core - EVPN just programs what goes where. QinQ only stacks VLAN tags and has no routed tunnel capability, so it doesn't fit the EVPN data-plane role. If it can cross a routed underlay as a proper encapsulation, it qualifies; if it's just VLAN tagging, it doesn't.

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