Rules for routing

The rules that you need to keep in mind when working with routes are:

• Virtual routes must end in the subareas where the session end points reside.
• Virtual route numbers must be defined the same in both directions but only at each end point. A virtual route definition does not need to be specified in every node in the path.
• Explicit routes do not have to flow in both directions, but must be the same in one direction from endpoint subarea to endpoint subarea.
• Explicit and virtual route rules apply in each network, not across SNI network boundaries.
• Transmission group numbers on the VR that you are using must be the same in both directions, but only between two nodes, not along the entire path.