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Chapter 4: Web-Based Management
GE-DS-82 and 82-PoE Ethernet Managed Switch User Manual 77
The Managed Switch supports multiple VLAN tags and can therefore be used in MAN
applications as a provider bridge, aggregating traffic from numerous independent
customer LANs into the MAN (Metro Access Network) space. One of the purposes of
the provider bridge is to recognize and use VLAN tags so that the VLANs in the MAN
space can be used independent of the customers' VLANs. This is accomplished by
adding a VLAN tag with a MAN-related VID for frames entering the MAN. When
leaving the MAN, the tag is stripped and the original VLAN tag with the customer-
related VID is again available.
This provides a tunneling mechanism to connect remote costumer VLANs through a
common MAN space without interfering with the VLAN tags. All tags use EtherType
0x8100 or 0x88A8, where 0x8100 is used for customer tags and 0x88A8 are used for
service provider tags.
In cases where a given service VLAN only has two member ports on the switch, the
learning can be disabled for the particular VLAN and can therefore rely on flooding as
the forwarding mechanism between the two ports. This way, the MAC table
requirements are reduced.
Q-in-Q Port Setting
The QinQ VLAN \ QinQ Port Setting screen in Figure 54 appears.
Figure 54: Q-in-Q Port Setting interface