H3C Technologies H3C S3100 Series Switches - Manual (Page 263)

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z
The rapid transition feature can be enabled on only root ports or alternate ports.
z
If you configure the rapid transition feature on a designated port, the feature does not take effect on
the port.
Configuring VLAN-VPN Tunnel
Currently, only S3100-SI series Ethernet Switches support the VLAN-VPN tunnel feature.
Introduction
The VLAN-VPN Tunnel function enables STP packets to be transparently transmitted between
geographically dispersed customer networks through specified VLAN VPNs in service provider
networks, through which spanning trees can be generated across these customer networks and are
independent of those of the service provider network.
As shown in Figure 1-9 , the upper part is the service provider network, and the lower part comprises the
customer networks. The service provider network comprises packet input/output devices, and the
customer network has networks A and B. On the service provider network, configure the arriving STP
packets at the input device to have MAC addresses in a special format, and reconvert them back to their
original formats at the output device. This is how transparent transmission is implemented over the
service provider network.
Figure 1-9 VLAN-VPN tunnel network hierarchy
Network
Network A Network B
Customer networks
Service provider network
Packet input/output
device
Packet input/output
device