Instruction manual

Glossary
CO
132 Strata DK General Description 6/00
CO Central Office—The facility which houses switching equipment that provides telephone
service (CO lines, E & M Tie lines, DID lines, Centrex lines, etc.) for the immediate
geographical area.
CODECs Coder/Decoder—Semiconductors that allow the system to process analog-to-digital and
digital-to-analog conversions.
CSU Channel Service Unit. Required between the DK PRI interface and the PRI line provider
interface in most locations of the U.S.
CNIS Calling Number Identification Services—Caller ID for ISDN. CNIS is calling party information
for outgoing and incoming calls sent to the ISDN network.
DADM Digital Add-on-Module—Optional device that connects to 2000-series digital telephones to
provide the telephones with 20 flexible feature buttons that can be assigned individually for
Direct Station Selection, System and Personal Speed Dial, and CO line access.
D-channel Used in ISDN. This channel transmit call control information (out-of-band signaling) for B-
channels. The D-channel is a logical, not physical channel.
DDCB Digital Door Phone/Lock Control Unit—A peripheral hardware unit compatible with
designated digital telephone circuits that supports optional door phones (MDFBs) and
provides door lock control.
DDSS Digital Direct Station Selection Console—A device that helps facilitate the processing of a
heavy load of incoming calls. The DDSS connects only to designated digital telephone
circuits, and is associated with a digital telephone.
DH Distributed Hunt.
DID Line Direct Inward Dialing line—Allows external callers to dial directly to an internal number.
DIL Direct In Line—Refers to two-way, standard CO trunk lines that are assigned to a particular
extension or hunt group.
DISA Direct Inward System Access—Enables an outside party to access the Strata DK system
internal stations or outgoing CO lines without having to go through an operator or automated
attendant. An optional security code may be set to prevent unauthorized access to outgoing
CO lines for through system calling.
DKT Digital Key Telephone.
[DN] Directory Number.
DNIS Dialed Number Identification Service—Telephone number of called party is sent to the Strata
DK over incoming DID or Tie lines. This feature is provided by some long distance telephone
companies.
DSS Direct Station Selection—Enables a telephone user (as well as a DSS console and ADM
user) to call another station with the touch of a flexible feature button.
DTMF Dual-tone Multi-frequency—Push-button tone dialing.
DVSU A subassembly that equips a digital telephone with the capability to receive Speaker Off-hook
Call Announce (OCA) calls. DVSU is not required to receive Handset OCA (HS-OCA).
EKT Electronic Key Telephone.
ESF Extended Super Frame.
FIFO First-In, First-Out.
HDCB Electronic Door Phone/Lock Control Unit—A peripheral hardware unit compatible with
designated electronic telephone circuits that supports optional door phones (MDFBs) and
provides door lock control.
Term Definition