Which term describes the ‘Always a reference point between a subscriber network and a service provider’?

• A. SD-WAN UNI
• B. UNI
• C. PVC
• D. TVC

Answer: (B)

The concept here is the boundary point where the subscriber’s network meets the service provider’s network. That fixed reference point is the User-Network Interface, or UNI. It’s the official term for the connection where customer equipment (like a CPE or SD-WAN edge device) interfaces with the provider’s network, marking the handoff and the point at which responsibility for maintenance and service typically shifts.

In SD-WAN contexts you’ll hear about SD-WAN UNI to emphasize that the SD-WAN edge terminates at this boundary, but the fundamental idea remains UNI—the standard demarcation between subscriber and provider. The other terms describe specific types of circuits within the provider’s network (for example, PVC referring to a persistent virtual circuit in older ATM networks) and do not denote the universal boundary between customer and provider.