REALIZATION OF A PASSIVE BROAD-BAND-NETWORK TERMINATION-1 (B-NT1) FORTHE OPTICAL USER-NETWORK INTERFACE

A new passive Broadband Network Termination 1 (B-NT1) as an alternativ e to the active B-NT1 for B-ISDN is described which supervises the U-B interface between B-LT and B-NT1. For this purpose, the B-LT generate s an additional pseudo noise (PN-)signal which is reflected at the pas sive B-NT1 and analysed by a correlation method in the B-LT. The alarm flow between B-LT and the B-NT2 remains unchanged by introducing a ne w reflection alarm REFL in the B-LT which is based on the evaluation o f the correlation signal and describes the condition of the U-B interf ace. The passive B-NT1 concept offers a more economical alternative fo r the network operator to provide Operation and Maintenance (OAM) on t he T-B and U-B interface.