MULTISERVER 500
98
DID
Direct Inward Dialing, a service offered by the
telephone company. It lets you dial an internal
extension without passing through the operator.
Billing does not start until the extension answers.
DISA
Direct Inward System Access, a service offered by a
PBX. It lets incoming calls to the PBX have dialing
access within the private network. May often be
protected by a dialed password. Billing starts at the
time when the PBX provides the dial tone.
DIT
Direct In Termination, a service offered by a PBX.
It lets incoming calls to the PBX be routed directly
to a selected telephone or group of telephones
without operator intervention. Billing does not
start until the telephone answers.
DSP
Digital Signal Processor, a microprocessor
incorporated in the Multiserver 500 and used for
voice compression and fax demodulation.
DTMF
Dual Tone Multifrequency, used for call addressing
in pushbutton telephones. Also known as
Multifrequency Push-Button (MFPB) in Europe.
Dynamic bandwidth allocation
See
DBA.
E&M
In industry usage, a signaling convention between
voice PBXs. As related to the Multiserver 500, an
interface module compatible with the tie-trunk side
of a voice PBX.
Extra gain
See
maximum output level
.
Fax, facsimile
Transmission of hardcopy images (written, typed, or
drawn material) through the voice/fax channel.
FX, foreign exchange service
A telephone service provided to a subscriber from a
central office which is located outside the
subscriber’s exchange area.
FXO, foreign exchange office
A voice/fax interface module that connects to the
station side of the local PBX or central office.
FXS, foreign exchange station
A voice/fax interface module that connects to the
telephone equipment at the subscriber’s foreign
exchange station.
Guaranteed rate
A Multiserver 500 configuration option (“rate” in
the configuration menus) that specifies the amount
of link bandwidth allocated to the synchronous data
channel when the voice/fax channel is in use.
Header
Pins on a circuit board onto which a jumper can be
installed for purposes of hardware configuration.
Hook
One of the Multiserver 500 options controlling
Dynamic Bandwidth Allocation (DBA). When
selected, it provides indication when the voice/fax
channel is in use.
Host
The central computer (or computer systems) that
provides primary data processing functions or data
base access.
Hz, Hertz
A measure of frequency or bandwidth equal to one
cycle per second.
Indicator lights
The light-emitting diodes (LEDs) on the front of
the Multiserver 500.
