Some companies have to wrestle with the decision of whether to use a private or a public-switched network. This decision is not an easy one because oftentimes the numbers do not play out well. The return on their investment just will not be there.
As a result, these organizations use a mix of services based on both private and public networks. The high-end usage services, heavy volumes between two or more major company locations, will be connected via private facilities; the lower volume locations will utilize the switched network. This usually works out better financially for the organization, because the costs can be fully justified on a location-by-location basis. Pressure to install private line facilities comes from the integration of voice, data, video, graphics, and facsimile transmissions. Only by combining these services across common circuitry will many organizations realize a true savings.
This introduction is meant to teach you about the functions and technology of a Central Office.
Analog to Digital Bandwidth
The Telephone Network
A Topology of Connection
Network Hierarchy (pre 1984)
Network Hierarchy (post 1984)
North American Numbering Plan
The Subscriber Extension
Local Access and Transport Areas
Wiring Connections: Hooking Things Up
Types of Communication
Lines Vs. Trunks
Foreign Exchange Signal