Service Provider. And these packets will be transmitted with double-tag across the public
networks.
The VLAN-VPN function provides you with the following benefits:
1.
Provides simple Layer 2 VPN solutions for small-sized LANs or intranets.
2.
Saves public network VLAN ID resource.
3.
You can have VLAN IDs of your own, which is independent of public network VLAN IDs.
4.
When the network of the Internet Service Provider is upgraded, the user’s network with a
relative independence can still work normally without changing the current configurations.
In addition, the switch supports the feature to adjust the TPID Values of VLAN VPN Packets.
TPID (Tag Protocol Identifier) is a field of the VLAN tag. IEEE 802.1Q specifies the value of TPID
to be 0x8100. This switch adopts the default value of TPID (0x8100) defined by the protocol.
Other manufacturers use other TPID values (such as 0x9100 or 0x9200) in the outer tags of
VLAN-VPN packets. To be compatible with devices coming from other manufacturers, this
switch can adjust the TPID values of VLAN-VPN packets globally. You can configure TPID
values by yourself. When a port receives a packet, this port will replace the TPID value in the
outer VLAN tag of this packet with the user-defined value and then send the packet again. Thus,
the VLAN-VPN packets sent to the public network can be recognized by devices of other
manufacturers.
The position of the TPID field in an Ethernet packet is the same as the position of the protocol
type field in the packet without VLAN Tag. Thus, to avoid confusion happening when the switch
forwards or receives a packet, you must not configure the following protocol type values listed
in the following table as the TPID value.
Protocol type
Value
ARP
0x0806
IP
0x0800
MPLS
0x8847/0x8848
IPX
0x8137
IS-IS
0x8000
LACP
0x8809
802.1X
0x888E
Table 7-3 Values of Ethernet frame protocol type in common use
This VLAN VPN function is implemented on the
VPN Config
,
VLAN Mapping
and
Port Enable
pages.
7.7.1
VLAN-VPN Config
On this page, you can configure the VLAN-VPN feature.
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