Ambiguous VLAN Support for IP sessions over ISG
Last Updated: November 29, 2012
The Ambiguous VLAN Support for IP Sessions over ISG feature allows network service providers to define a range or ranges of inner VLANs and create queue-in-queue (QinQ) VLANs on demand. This is done by specifying a range for the inner VLAN tag in the IEEE 802.1Q-in-Q while maintaining a single outer VLAN tag for each subinterface. This module explains the Ambiguous VLAN Support for IP Sessions over ISG feature and how to configure it.
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Restrictions for Ambiguous VLAN Support for IP Sessions over ISG
Ambiguous VLANs are currently supported only for Inteliigent Services Gateway (ISG) sessions.
IP sessions and PPP sessions are not supported on the same ambiguous subinterfaces. Hence, different ranges need to be specified for the outer VLAN tags for both IP sessions and PPP sessions.
Only a limited feature set will be applied to each queue-in-queue (QinQ) pair as no subinterfaces are created for each QinQ pair. The available features include those applicable to the ISG session and those applicable to the ambiguous VLAN interface.
This feature is restricted to Layer 2 unclassified MAC and DHCP-initiated ISG sessions.
IPv6 sessions are not supported.
Information About Configuring Ambiguous VLAN Support for IP Sessions over ISG
Benefits of Ambiguous VLAN Support for IP Sessions over ISG
Ambiguous VLAN implementation for IP sessions in Intelligent Services Gateway (ISG) has the following benefits:
The service provider only needs to know the end-user VLAN ranges instead of the individual end-user VLAN IDs.
The ambiguous VLAN feature allows the configuration of multiple VLANs under one subinterface which leads to better Interface Descriptor Block (IDB) utilization.
Where to Go Next
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