Q-In-Q; Global Settings; Figure 28: L2 Switching > Q-In-Q > Global Settings; Table 25: Q-In-Q Global Settings - Allied Telesis IS230-10GP Web User Manual

Q-in-Q

Q-in-Q is commonly referred as VLAN stacking in which VLANs are nested
by adding two tags to each frame instead of one. Network service provider
and users both can use VLANs and makes it possible to have more than
the 4094 separate VLANs allowed by 802.1Q.
There are three ways in which a machine can be connected to a network
carrying double-tagged 802.1ad traffic:
via a untagged port, where both inner and outer VLANs are handled by

the switch or switches (so the attached machine sees ordinary
Ethernet frames);
via a single-tagged (tunnel) port, where the outer VLAN only is handled

by the switch (so the attached machine sees single-tagged 802.1Q
VLAN frames); or
via a double-tagged (trunk) port, where both inner and outer VLANs

are handled by the attached machine (which sees double-tagged
802.1ad VLAN frames).

Global Settings

The Global Settings page allows you to set the outer VLAN Ethertype
setting.
To access this page, click L2 Switching > Q-in-Q > Global Settings.
The following table describes the items in Figure 28.
Item
Outer VLAN Ether-
type
Apply
The QinQ Global Information settings in the ensuing table are
informational only: Outer VLAN Ethertype.
Figure 28. L2 Switching > Q-in-Q > Global Settings
Table 25. Q-in-Q Global Settings
Description
Enter the outer VLAN handled by the switch giving the attached
machine a single-tagged 802.1Q VLAN frame.
Click Apply to save the values and update the screen.
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