Telephony 101

Question 1

What is Telephony?

Answer 1

The science of converting sound into electrical signals then back to sound again using telephones.

Question 2

Describe original phone systems.

Answer 2

Began with (POTS) Plain Old Telephone Systems that connected to (CO) Central Office with a switch board operators.

As tech advanced, operators were replaced by switch boards and telephone numbers via rotary and then push pads.

Created (PSTN) Public Switch Telephone Network for long distance calling connecting the (CO)’s..

Question 3

What are “Key System” phone services?

Answer 3

Multiple Lines to a single phone

Hold

Transfer

Question 4

What are “Centrex” (Central Office Exchange) phone services?

Answer 4

Allowed for lease of a section at the Switchboard/CO for calling to several geographic locations as if they were in the same building.

Many features:
Handled at CO
Location Independent

Question 5

What is (PBX) Private Branch Exchange?

Answer 5

Advance features and call routing is handled at the business site. It gave advantages of PODS and Key Systems and allowed them to be controlled in house.

The only downside - It is limited geographically to only serve one location.

Question 6

What is (VOIP) Voice Over Internet Protocal?

Answer 6

internet based data and calling.

Caller > Switches & Routers > Internet > Central Office (CO) > Public Switches Telephone Networks (PSTN) > Receiver Caller

Question 7

What are the company origins?

Answer 7

Cellular South > C Spire Wireless > (Merge with Telepak Networks) > C Spire Business/VOIP services