Andere Kunden interessierten sich auch für
![The Telephone Cases]( "The Telephone Cases")
The Telephone Cases22,99 €![Uniform System of Accounts for Telephone Companies, as Prescribed by the Interstate Commerce Commission, in Accordance With Section 20 of the Act to R]( "Uniform System of Accounts for Telephone Companies, as Prescribed by the Interstate Commerce Commission, in Accordance With Section 20 of the Act to R")
Uniform System of Accounts for Telephone Companies, as Prescribed by the Interstate Commerce Commission, in Accordance With Section 20 of the Act to R32,99 €![Introduction to Telephones and Telephone Systems Third Edition]( "Introduction to Telephones and Telephone Systems Third Edition")
Introduction to Telephones and Telephone Systems Third Edition94,99 €![The History of the Telephone]( "The History of the Telephone")
The History of the Telephone15,99 €![Design of Telephone System of Biscast]( "Design of Telephone System of Biscast")
Design of Telephone System of Biscast36,99 €![Telephone Activated Remote Access Switch]( "Telephone Activated Remote Access Switch")
Telephone Activated Remote Access Switch36,99 €![An Analysis of Computer and Telephone Usage in the New York City Metropolitan Area]( "An Analysis of Computer and Telephone Usage in the New York City Metropolitan Area")
An Analysis of Computer and Telephone Usage in the New York City Metropolitan Area17,99 €
High Quality Content by WIKIPEDIA articles! A telephone numbering plan is a system of allocating and routing telephone numbers in a telephone network. A closed numbering plan, such as found in North America, features fixed length area codes and local numbers. An open numbering plan features variance in length of area code or local number, or both. The term dial plan should not be confused with numbering plan. In early telephone systems, connections were made in the central office by telephone operators using patch cords to connect one party to another. If a person wanted to make a phone call, he or she would pick up a phone and wind a crank on the side. The crank was a small generator that would light a lamp at the central office. An operator would see the light and insert their patch cord into a socket and assist the customer with the call connection. The operator would use patch cords to connect the caller to the person being called. If the party being called was in another exchange, the operator would use a patch cord to connect to another exchange where an operator elsewhere would finish the connection. As technology advanced, electro-mechanical switches were introduced and calls were made using "rotary dials".