This application is for the communication infrastructure of the conventional railway system in an East Asian country. The purpose of the communication network is to transport voice communication across the network and to report alarms between stations. The drawing is a sample of the entire infrastructure focusing on a particular region within the country.
The system’s backbone is an optical STM-16 ring SNCP (Subnetwork Connection Protection) that is part of a larger, industrial strength SDH network. Sub-rings of STM-4 and STM-1 speeds were also implemented. The lower speeds roughly corresponded to the size of the city and the remoteness of the station.
Loop provided the total solution from STM-16 down to 64kbps for cross-connection. The NMS system also managed SDH + PDH connections, supporting end-to-end circuit creation and management. This reduced the required human resources in the management center and saved costs on end-to-end maintenance.