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Määritelmät

Substantiivi

1. (telephony) Any equipment that establishes connections between telephones.
2. (telephony, chiefly historical) The rooms or building housing such equipment (a central office, as it was termed by the Bell System).
3. (telephony, historical) A local or locoregional network of such switched connections, of which a central office was the hub; the local company formed to create and maintain this network and its central office.
4. (telephony) The portion of a telephone number representing that network, among the other networks of the larger system: the central office code. In the North American Numbering Plan, this is the "555" portion of "+1-212-555-6789".