Bpdu Tunnel Configuration - Huawei Quidway S5600 Series Operation Manual

Operation Manual – VLAN VPN
Quidway S5600 Series Ethernet Switches-Release 1510
Before the device in the operator's network forwards the packet to the destination
user network, the device restores the original protocol-specific MAC address. This
ensures the data portion of the packet is consistent with that before the packet
enters the tunnel. So, a tunnel here acts as a local link for user devices. It enables
Layer 2 protocol packets to travel across a logical LAN.
Receiving/sending Receiving/sending
device device
Figure 2-1 BPDU Tunnel network hierarchy
Figure 2-2 and Figure 2-3 show the structure of a BPDU packet before and after it enter
a BPDU tunnel.
Destination MAC address Destination MAC address
(Protocol-speci f ic MAC) (Protocol-speci f ic MAC)
Figure 2-2 The structure of a BPDU packet before it enters a BPDU tunnel
Destination MAC address Destination MAC address
(Recognizable by user) (Recognizable by user)
Figure 2-3 The structure of a BPDU packet after it enters a BPDU tunnel

2.2 BPDU Tunnel Configuration

You can establish BPDU tunnels between S5600 series Ethernet switches for the
packets of the following protocols:
ALCP (link aggregation control protocol)
NDP (neighbor discovery protocol)
Proprietary protocols, including CDP and VTP
Operator's network Operator's network
Network A Network A Network A Network A
Source MAC Source MAC
address address
Source MAC Source MAC
address address
Huawei Technologies Proprietary
Chapter 2 BPDU Tunnel Configuration
Network Network Network Network
User's network User's network
BPDU Data BPDU Data FCS FCS
BPDU Data BPDU Data FCS FCS
2-2
Receiving/sending Receiving/sending
device device
Network B Network B Network B Network B