Radio common carrier (RCC) – A communications carrier that provides radio paging and mobile telephone services to the public.
Random access memory (RAM) – Portion of a computer storage which can be accessed non-sequentially and is considered the working memory.
Raster – Scanning pattern used in generating, recording or reproducing television, facsimile or graphics images on a screen.
Rate center – Specific geographic location used by LECs to determine interchange mileage for rate determination purposes. [The rate center for an exchange is generally a centrally located point within the exchange area.]
Rate mileage – Airline distance from one subscriber’s rate center to all other LEC rate centers.
Rate periods – Division of a day into categories for charges: day, evening, night/weekend.
Re-homing - A network change which involves moving customer services from one switching center to another and establishing the necessary trunking facilities to do so.
Read only memory (ROM) – Portion of computer memory which is programmed electrically by the manufacturer, is unchangeable and is unaffected by a power loss.
Real-time ANI – Delivery of automatic number identification (either the full phone number of the calling party or the NPA & NXX) simultaneously with the call. [ANI is used by telephone companies for routing and billing.]
Record – A single, logically associated information group.
Redundancy – (1) Duplicate standby equipment or facilities that are activated to insure continuous service or minimize the effect of equipment malfunctions. (2) A repetition of information. (3) Insertion of information which is not new (example: the use of check bits and check characters in data communication).
Regeneration – Process of receiving distorted signal pulses and from them recreating new pulses at the correct repetition rate, pulse amplitude and pulse width.
Regional Bell Operating Company (RBOC) – The seven holding companies into which the 22 Bell System local telephone companies were assigned at divestiture: Pacific Telesis, U.S. West, Southwestern Bell Corp., Ameritech, BellSouth, Bell Atlantic, NY NEX.
Remote access – (1) PABX feature that allows a user at a remote location to access PABX features by telephone (for example, WATS lines); individual authorization codes are usually required. (2) Ability of transmission points to gain access to a computer which is at a different location.
Repeater – (1) A device which serves as an interface between circuits, receiving signals from one circuit and transmitting them to the other. (2) A one- or two-way device which amplifies an input signal for retransmission. (3) A device that amplifies, reshapes, retimes or performs a combination of these functions on an input pulse for re-transmission.
Repeating coil – Separates one section of a telephone circuit from another, with no direct current link between the sections. [Telephone industry's term for a voice frequency transformer.]
Resale carrier – Company which leases circuits or services from a major carrier and resells them to individual users.
Restoration – Re-establishment of services, usually following the breakdown of a system, on a priority basis.
Retard coil – A coil having a large inductance which slows sudden changes of the current flow; a choke.
Reverse channel - A simultaneous data path in the reverse direction over a half-duplex facility; used for positive/negative acknowledgements of previously received data blocks.
Red video signal – A video transmission in which the red (R) green (G) and blue (B) picture components are present as individual signals. [Synchronization information may be included with the G signal or may be separate.]
Ring – To activate a called subscriber’s telephone bell.
Ringback – Signal used by the operator at the receiving end of an established connection to recall an operator at originating end. Synonym: Audible Ringing Tone.
Ringdown – A circuit or a method of signaling where the incoming signal is actuated by alternating current over the circuit.
Rotary dial – A mechanism having a 10-hole finger wheel which when wound and released causes pulsing contacts to interrupt the line current and operate the central office selecting equipment in accordance with the digit dialed.
Rotary hunt - Method in which incoming calls seek out an idle circuit in a prearranged multi-circuit group and find the next open line to establish a through circuit.
Route advance – Feature of Sprint 800 Service which automatically assigns an alternate communications path when the primary path is busy; calls are routed to DDD lines.
Route optimization – Method for automatic selection of the least costly facility for transmission of a call. Synonym: Least Cost Routing.