Can PPPoE tunnels be added to a bridge?

• A. Yes
• B. No
• C. Only in certain scenarios
• D. Not supported

Answer: (A)

The move is to treat PPPoE traffic like any other Ethernet frames within a Layer 2 domain. A bridge in RouterOS is essentially a small switch that forwards frames between its member ports. PPPoE is encapsulated over Ethernet (PPPoE discovery and session frames are normal Ethernet frames with specific Ethertypes). Because of that, a PPPoE tunnel interface can be added to a bridge and participate in the same forwarding as the other bridge ports. In other words, the PPPoE frames can travel across the bridge to reach the PPPoE server and for the server to see the proper session traffic.

This works because the bridge doesn’t care what the frame carries as long as it’s Ethernet; it simply forwards it to the appropriate ports in the same broadcast domain. When configuring, you’d typically ensure the PPPoE interface is part of the bridge so its frames are treated like any other bridged traffic, while keeping PPPoE negotiations on that interface. There aren’t fundamental restrictions preventing this; it’s a normal part of how bridging and PPPoE operate together.