3com WX3000 Manuel D’Utilisation

 

1-1 

 

z 

The term switch used throughout this chapter refers to a switching device in a generic sense or the 

switching engine of a unified switch in the WX3000 series. 

z 

The sample output information in this manual was created on the WX3024. The output information 

on your device may vary. 

 

Virtual private network (VPN) is a new technology that emerges with the expansion of the Internet. It can 

be used for establishing private networks over the public network. With VPN, you can specify to process 

packets on the client or the access end of the service provider in specific ways, establish dedicated 

tunnels for user traffic on public network devices, and thus improve data security.  

VLAN-VPN feature is a simple yet flexible Layer 2 tunneling technology. It tags private network packets 

with outer VLAN tags, thus enabling the packets to be transmitted through the service providers’ 

backbone networks with both inner and outer VLAN tags. In public networks, packets of this type are 

transmitted by their outer VLAN tags (that is, the VLAN tags of public networks), and the inner VLAN 

tags are treated as part of the payload.  

 describes the structure of the packets with single-layer VLAN tags. 

Figure 1-1 Structure of packets with single-layer VLAN tags 

Destination MAC address

0

31

Data

Source MAC address

15

VLAN Tag

 

 

 describes the structure of the packets with double-layer VLAN tags.