Black Box 5000 manual 259

ms, millisecond — One-thousandth of a second.

multiplexor — A device that divides a composite signal among several channels.

mux — Short for multiplexor.

mux link — A Multiserver-to-feeder-mux composite link.

NAK, negative acknowledgment — A control character which indicates that the previous transmission block was received in error.

node — Any Multiserver or feeder mux in the Multiserver network. Each node has a unique name (ID) and number.

node reset — Resets the unit to either the current configuration (warm start) or to the factory defaults (cold start).

nonvolatile — A term used to describe a data storage device (memory) that retains its contents when power is lost.

null character — A character (usually all bits set to Mark) used to allow time for a printer’s mechanical actions to take place so that the printer will be ready to print the next data character. Sometimes called idle character.

NULL password — A password configured for no password. A password can be deleted by configuring a NULL password.

number of rings — An OPX-strapped switching- configuration option. On outgoing calls, specifies number of ringbacks before the second dial tone.

off-hook— A line condition caused when a telephone handset is removed from its cradle, if the line is active.

on-hook— A line condition that exists when a telephone handset is resting in its cradle, if the line is active.

Glossary

OPX, off-premises extension — In industry usage, an off-premise telephone extension. As related to the Multiserver voice/fax module, a strapping option for compatibility with the station side of a voice PBX.

pad character — A character inserted to fill a blank time slot in a synchronous transmission or to fulfill a character-count requirement in a transmission of fixed block length. Leading pad characters help establish synchronization, and trailing pad characters prevent the dropping of the RLSD/RTS signal too soon after the end of a frame.

parity, parity bit — A bit added to a character to ensure that the total number of ones in a grouping of bits is either always even for even parity, or odd for odd parity. This permits detection of signal errors.

Part 15, FCC — A part of the FCC body of rules that defines the restrictions to the level of electromagnetic emissions for an electronic device.

Part 68, FCC — A part of the FCC body of rules that defines the technical requirements that an electronic device must meet before it can be connected to the telephone network.

PBX, private branch exchange — A privately owned phone system installed within the premises of an organization. It allows communication among users within the organization, as well as between those users and the outside world. It differs from a key telephone system in that the user must dial an access number, such as 9, to get an outside line.

PDN, public data network — A network established and operated by a PTT, common carrier, or private operating company for the specific purpose of providing data-communication services to the public.

PLARC, private line automatic ringdown

circuit — A typical voice application where KTS is configured at both ends. When one handset is lifted, the other one rings.

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