Telephone Network
The basic voice communication network is the largest and one of the oldest twentieth century communications networks.
Voice calls represent more than half of the amount spent on communications in corporations
How does it work:
- Your telephone is connected to the telephone company’s end office (also called central office or exchange office) where switching is performed
- Switching includes identifying and connecting independent
transmission circuits to form a continuous path from your telephone to the telephone you are calling
- telephone number is used as an address in order to search out the telephone you are calling.
Calls made within the same end office or interoffice trunks are local calls
Calls that use tandem trunks (lines between end office and tandem office or toll office) and tandem office are unit calls
calls which use toll trunks and toll office are long distance calls