NNI

NNI is expanded two ways:

1. network-to-network interface

   An NNI is a standard interface between two ATM devices or two frame relay devices.

   An NNI is also a port that resides on a PE bridge or a transit bridge, and connects to a service provider network.

2. network node interface

   NNI is the interface between two ATM network devices that operate under different administrative domains, such as a vendor ATM switch and an ATM switch from another vendor.