PLANET WGSW-52040 - Manual (Page 147)

2. Configure the port to support the tunnel
Command Explanation
Port mode
bpdu-tunnel {stp|gvrp|uldp|lacp|dot1x}
no bpdu-tunnel {stp|gvrp|uldp|lacp|dot1x}
Enable the port to support the tunnel,
the no command disables the
function.
18.3 Examples of bpdu-tunnel
Special lines are used in a service provider network to build user-specific Layer 2 networks. As
a result, a user network is broken down into parts located at different sides of the service
provider network. As shown in Figure, User A has two devices (CE 1 and CE 2) and both
devices belong to the same VLAN. User’s network is divided into network 1 and network 2,
which are connected by the service provider network. When Layer 2 protocol packets cannot
implement the passthrough across the service provider network, the user’s network cannot
process independent Layer 2 protocol calculation (for example, spanning tree calculation), so
they affect each other.
Figure 18-2: BPDU Tunnel application environment
With BPDU Tunnel, Layer 2 protocol packets from user’s networks can be passed through
over the service provider network in the following work flow:
1. After receiving a Layer 2 protocol packet from network 1 of user A, PE 1 in the service
provider network encapsulates the packet, replaces its destination MAC address with a
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