The PSTN can be defined as ________ and facilities involved in connecting a calling telephone to the called telephone regardless of where it might be.

In PSTN, connection takes place in many levels that involve an array of systems and _________.

It consists of basic circuits that power the telephones and provides all the basic functions such as ringing, dial tone and dialing supervision

ON-HOOK means __________

_________ is needed for long loop scale transmission

________ the ringer when picked up for use by a subscriber

Functions that monitor local loop conditions and other services.

functions that converts Analog to Digital, and vice versa

for simultaneous two-way conversation on a single pair of wires.

To check the status and quality of subscriber lines

It contains all the equipment that operates the telephone

Connects COs without direct connection to CPEs

Symbols used to describe COs

Symbols used to describe transmission cable

Symbols used to describe subscriber

Symbols used to describe PBX

This represents ________

________is a direct link between two telephone exchanges or switchboards that are a considerable distance apart

PBX and subscribers

local loop and the switch

End office and core switches connection

Control of calling

It is responsible for connecting a telephone handset to the telephone system

Basic structure of a local calling area