R3303-HP HSR6800 Routers Layer 2 - LAN Switching Configuration Guide

Figure 28 BPDU tunneling implementation

The upper section of Figure 28 represents the service provider network (ISP network). The lower section,

including User A network 1 and User A network 2, represents the customer networks. Enabling BPDU

tunneling on edge devices (PE 1 and PE 2) in the service provider network allows BPDUs of User A

network 1 and User A network 2 to be transparently transmitted through the service provider network.

This ensures consistent spanning tree calculation throughout User A network, without affecting the

spanning tree calculation of the service provider network.

Assume that a BPDU is sent from User A network 1 to User A network 2:

1. At the ingress of the service provider network, PE 1 changes the destination MAC address of the

BPDU from 0x0180-C200-0000 to a special multicast MAC address, 0x010F-E200-0003 (the

default multicast MAC address), for example. In the service provider network, the modified BPDU

is forwarded as a data packet in the VLAN assigned to User A.

2. At the egress of the service provider network, PE 2 recognizes the BPDU with the destination MAC

address 0x010F-E200-0003, restores its original destination MAC address 0x0180-C200-0000,

and then sends the BPDU to CE 2.

Through configuration, make sure the VLAN tags carried in BPDUs are neither changed nor removed

during the transparent transmission in the service provider network. Otherwise, the devices in the service

provider network will fail to transparently transmit the customer network BPDUs correctly.

Configuration prerequisites

Before configuring BPDU tunneling for a protocol, perform the following tasks:

• Enable the protocol in the customer network.

• Assign the port on which you want to enable BPDU tunneling on the PE device and the connected

port on the CE device to the same VLAN.

• Configure ports that connect network devices in the service provider network as trunk ports that

allow packets of any VLAN to pass through.

Enabling BPDU tunneling

Configuration guidelines

• You can enable BPDU tunneling for different protocols in different views. Settings made in Layer 2

Ethernet interface view or Layer 2 aggregate interface view take effect only on the current port.

Settings made in port group view take effect on all ports in the port group.