Black Box 5000 manual 260, PTT, Post, Telephone, and Telegraph

Multiserver 5000

point-to-point— A communications circuit or transmission path connecting two points. In the Multiserver unit that connection can be force- connected (dedicated point-to-point) or switched (switched point-to-point).

port — A physical connector on the back of the Multiserver unit. It can be configured as a link, or as a user channel. Also, an interface capable of attaching to a device for communications with another device.

protocol — The means used to control the orderly exchange of information between stations of a data link or on a data communications network or system.

PTT, Post, Telephone, and Telegraph

Authority — A government agency that functions as the communications common carrier and administrator in many areas of the world.

pulse dialing — Method used for call addressing in rotary telephones by short pulses of on- hook/off-hook. Also known as decadic pulsing in Europe.

QAM, quadrature amplitude modulation — A modulation technique that combines phase and amplitude modulation to increase the number of bits per baud.

RAM, random access memory — A storage device into which data can be entered (written) and read; usually (but not always) a volatile semiconductor memory.

Rapid Relay technology — Four technologies (data compression, speech compression, Fast-Packet multiplexing, and automatic fax demodulation) combined and used in Multiserver products.

RD, received data — An RS-232 data signal received by the DTE from a DCE.

receive inhibit — A configuration option that prevents the voice/fax channel from receiving calls.

remote analog loopback — An analog loopback that forms the loop at the line (analog output) side of the remote modem.

remote channel loopback — A channel loopback that forms the loop at the input (channel side) of the remote multiplexor.

remote composite loopback — A link loopback that forms the loop at the output (composite side) of the remote multiplexor.

remote digital loopback — A digital loopback that forms the loop at the input side of the remote modem.

reorder — In a switching mode, the response to most unsuccessful call attempts.

repeated ring — A configuration option for a KTS- strapped voice/fax channel. When repeated ring is configured, the local voice/fax channel rings the attached telephone set in response to a remote PBX ringing signal.

ringdown — Causes the local telephone to ring when the remote telephone is lifted off-hook, and vice versa.

RI, ring indicator — An RS-232 interface signal, sent from the modem to the DTE, that indicates that an incoming call is present.

RJ-type connector — A modular connector that complies with certain telco standards.

ROM, read-only memory — A nonvolatile semiconductor storage device manufactured with predefined contents.

RS-232— An EIA-recommended standard that is the most common for connecting serial data- processing devices. RS-232 specifies the electrical characteristics of the signals in cables that connect a DTE to a DCE. An RS-232 standard is functionally identical to CCITT V.24/V.28.

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