network interface device (MEF) (NID)

The Network Interface Device (NID) is a network termination device defined by the Metro Ethernet Forum ( MEF), IEEE Working Group802.1 and the International Telecommunication Union( ITU) to support Operation, Administration, and Maintenance( OAM) for Ethernet services.

Such a network terminating device provides the defined transition between the last mile of the operator network and the customer network. It is crucial for the transition of Ethernet services in the access network and ensures the agreed quality characteristics for the customer.

The network terminating device is always located in the data path and must therefore operate extremely reliably; it must not generate any significant delay or jitter and must not impair the transmission quality. It should monitor the data stream, have filter functions and be able to prove the allocated bandwidths for monitoring the service level agreements( SLA).