The Provider Bridging feature of VLAN Module in Intelligent Switching Solution ( ISS) enables a service provider to offer an equivalent of separate VLANs to a number of separate customers. Transparent communication between different customer networks at different locations through the provider networks is achieved through the Provider Bridges. In ISS, Layer 2 stacks act as Customer Bridges or Provider Bridges. An administrator chooses the type of bridge during the system initialization or when the system is running.The following are the different kinds of Provider Bridges:
Q-in-Q Bridge is a type of proprietary bridge in which transparent communication between the customer networks is possible by using the customer tags.
In the current version of ISS, only Customer Bridges are supported.
During system initialization, ISS takes the value of bridge mode from issnvram.txt. The administrator configures the type of bridge in issnvram.txt.