The Central Office Terminal (COT) and Remote Terminal (RT) are desired elements of the FLC-A network. They are connected to each other using high-speed optical links. The COT is allocated at the Central Office and is providing connection of the network with PSTN, X.25 and other systems.  The RT is allocated on the customer premises and is used for connection of black phones, ISDN, leased lines, pay phones and other to the network.
The channel bank is the device that is used for multiplexing and demultiplexing into one channel. Both terminals are created of a common shelf and channel banks.

 

Common shelf functions are:

 

• system power supply;
• clock synchronisation;
• SDH multiplexing/demultiplexing;
• equipment management.

Channel bank is using different channel cards that are providing functions:

 

• black phone services;
• pay phone services;
• PABX connections;
• data services with speeds of 2.4-54 Kbps;
• data services with speeds of n multiple of 64 Kbps.

System itself can provide services for up to 2000 voice channels and speed of 155 Mbps (STM-1). This capacity allows to install single FLC system for most of the buildings, while large buildings might require multiple systems. Four optical cores are used for interconnection between RT and COT. Two cables are used for protection, while two other are used for one bidirectional connection.