BPDU Tunnel Configuration

Bridge protocol data units (BPDUs) are used to transmit information for the spanning tree calculation on user networks. The path along which BPDUs are transparently transmitted over a carrier network is known as a Layer 2 protocol tunnel or a BPDU tunnel.

Overview of BPDU Tunneling: A bridge protocol data unit (BPDU) tunnel is a path along which BPDUs are transparently transmitted over a carrier network.

Configuration Precautions for BPDU Tunnel

Configuring Interface-based BPDU Tunneling Function: When each interface of devices on a carrier network is connected to only one user network, you can configure interface-based bridge protocol data unit (BPDU) tunneling to transparently transmit BPDUs from different user networks over the carrier network.

Configuring VLAN-based BPDU Tunneling Function: If each user-side interface on a PE is connected to multiple CEs, BPDUs sent from user networks must carry VLAN tags to identify these user networks. To transparently transmit BPDUs from user networks over the carrier network, deploy VLAN-based BPDU tunneling.

Configuring QinQ-based BPDU Tunneling Function: If each user-side interface on a provider edge (PE) is connected to multiple customer edges (CEs), bridge protocol data units (BPDUs) sent from user networks must carry virtual local area network (VLAN) tags to identify these user networks. To transparently transmit BPDUs from user networks over the carrier network and save VLAN ID resources for the carrier network, deploy QinQ-based BPDU tunneling (QinQ is short for 802.1Q in 802.1Q).

Configuration Examples for BPDU Tunneling: This section provides BPDU tunneling configuration examples.