D-Link DES-3028 Product Manual - Page 110

QinQ DES-3028 DES-3028P DES-3028G DES-3052 DES-3052P Layer 2 Fast Ethernet Managed Switch This function allows the user to enable or disable the QinQ function. QinQ is designed for service providers to carry traffic from multiple users across a network. QinQ is used to maintain customer specific VLAN and Layer 2 protocol configurations even when the same VLAN ID is being used by different customers. This is achieved by inserting SPVLAN tags into the customer's frames when they enter the service provider's network, and then removing the tags when the frames leave the network. Customers of a service provider may have different or specific requirements regarding their internal VLAN IDs and the number of VLANs that can be supported. Therefore customers in the same service provider network may have VLAN ranges that overlap, which might cause traffic to become mixed up. So assigning a unique range of VLAN IDs to each customer might cause restrictions on some of their configurations requiring intense processing of VLAN mapping tables which may exceed the VLAN mapping limit. QinQ uses a single service provider VLAN (SPVLAN) for customers who have multiple VLANs. Customer's VLAN IDs are segregated within the service provider's network even when they use the same customer specific VLAN ID. QinQ expands the VLAN space available while preserving the customer's original tagged packets and adding SPVLAN tags to each new frame. To view this window click L2 Features > QinQ. Figure 7- 10. QinQ Global State Settings window The following fields can be set: Parameter Description QinQ Global State Use the pull down menu to Enable or Disable the QinQ Global State. From Port...To Port A consecutive group of ports that are part of the VLAN configuration starting with the selected port. 96