Telephone Network

Telephone Network is used to provide voice communication. Telephone Network uses Circuit Switching. Originally, the entire network was referred to as a plain old telephone system (POTS) which uses analog signals. With the advancement of technology, i.e. in the computer era, there comes a feature to carry data in addition to voice. Today’s network is both analogous and digital.

Major Components of Telephone Network: There are three major components of the telephone network:

1.      Local loops

2.      Trunks

3.      Switching Offices

There are various levels of switching offices such as end offices, tandem offices, and regional offices. The entire telephone network is as shown in the following figure:

A telephone system

Local Loops: Local Loops are the twisted pair cables that are used to connect a subscriber telephone to the nearest end office or local central office. For voice purposes, its bandwidth is 4000 Hz. It is very interesting to examine the telephone number that is associated with each local loop. The office is defined by the first three digits and the local loop number is defined by the next four digits defines.

Trunks: It is a type of transmission medium used to handle the communication between offices. Through multiplexing, trunks can handle hundreds or thousands of connections. Mainly transmission is performed through optical fibers or satellite links.

Switching Offices: As there is a permanent physical link between any two subscribers. To avoid this, the telephone company uses switches that are located in switching offices. A switch is able to connect various loops or trunks and allows a connection between different subscribes.

Switching offices

Advantages of Telephone Network:

·         It is a circuit-switched network.

·         There is no transmission delay as any receiver can be selected.

·         It is cheap in price because it is a widely spread network.

Disadvantages of Telephone Network:

·          It requires a large time for connection.

·         It has a low transmission speed.

Applications of Telephone Network:

·         It helps to connect people.

·         It is used by business organizations to advertise their products.

·         It is also used around the world for recreational purposes.