User’s Manual of NS2503-24P/2C
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4.4.6.2 Q-in-Q Tunnel Setting
Business customers of service providers often have specific requirements for VLAN IDs and the number of VLANs to be
supported. The VLAN ranges required by different customers in the same service-provider network might overlap, and traffic of
customers through the infrastructure might be mixed. Assigning a unique range of VLAN IDs to each customer would restrict
customer configurations and could easily exceed the VLAN limit (4096) of the IEEE 802.1Q specification.
Using the QinQ feature, service providers can use a single VLAN to support customers who have multiple VLANs. Customer
VLAN IDs are preserved, and traffic from different customers is segregated within the service-provider network, even when they
appear to be in the same VLAN. Using QinQ expands VLAN space by using a VLAN-in-VLAN hierarchy and retagging the
tagged packets. A port configured to support QinQ is called a QinQ user-port. A port configured to support QinQ Uplink is called
a QinQ uplink-port.
Figure 4-4-11:
Q-in-Q Tunnel Setting Interface Screenshot
To configure QinQ Port
1.
Enable global QinQ function: select
QinQ
enable "
Enable
".
2. Fill
QinQ
Tpid.
3.
Enable port QinQ function: select QinQ checkbox for special port.
4.
Enable port QinQ Uplink function: select QinQ Uplink checkbox for special port.