User–network interface

In telecommunications, a User Network Interface (UNI) is a demarcation point between the responsibility of the service provider and the responsibility of the subscriber. This is distinct from a Network to Network Interface (NNI) that defines a similar interface between provider networks.

The Metro Ethernet Forum's Metro Ethernet Network UNI specification defines a bidirectional Ethernet reference point for Ethernet service delivery.

The Optical Internetworking Forum defines a UNI software interface for user systems to request a network connection from an ASON/GMPLS control plane.

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