TeleCom Glossary

0-9ABCDEFGHIJKLMNOPQRSTUVWXYZ
Glossary: D
DACS See Digital Access Cross-Connect System.
Data communications equipment (DCE) The interfacing equipment sometimes required to couple the data terminal equipment (DTE) into a transmission circuit or channel. Also couples a transmission circuit or channel to the DTE. Also known as Data Circuit-Terminating Equipment.
Data Exchange Interface (DXI and DXI/SNI) "(DXI) An SMDS interface between the customer and the network used at low speeds
Data port The point of access to a computer that uses trunks or lines for sending or receiving data.
Data service unit (DSU) "A device that transmits digital data on transmission facilities. Typically
Data terminal equipment (DTE) Equipment consisting of digital end instruments. Converts user information into data signals for transmission. Also reconverts received data signals into user information.
DATP table "The system configuration chart for the 3210 and 3216 Access Control Shelves in the MTAU
DATS Digital-Analog Test System
DATS maintenance "The process of setting up
DAU DSL Analyzer Unit
DBM Database Manager
dBm (decibels above one milliwatt) A logarithmic measure of the electrical power referred to one milliwatt.
dBm0 Decibel level relative to TLP
dBrn Decibels above reference noise
dBrn (decibels above reference noise) "The noise power relative to one picowatt
dBrnC "The power
DBS Database Screen Editor
DCD Data Carrier Detect
DCTE Data Circuit-Terminating Equipment
DCN Data Communications Network
DCP Detached Control Processor
DCS See Digital Cross-connect System.
DCS Concentrator "A device used to collect the test access digroups (TADs) of many digital cross-connect systems (DCSs). Once the TADs have been collected in one location
DDD Direct Distance Dialing
DDF Digital Distribution Frame
DDM Digital Data Multiplexer
DDS See Digital Data Service.
DDS Test Unit (DTU) The Hekimian 6302 test set that provides bidirectional DS1 and DS0A/DS0B interfaces. T1 and subrate access and testing require these interfaces.
Decibel (dB) The unit for measuring the relative power of a sound or strength of an electrical signal on a logarithmic scale.
Degraded minute A minute is considered degraded if it has all SES removed and has more than 93 CRC-6 violations or 93 frame bit errors.
Demodulation The process of restoring a signal to its original form at the receiving end of a transmission system.
DHCP Dynamic Host Configuration Protocol
Dialback number "The phone number associated with the automatic error reporting function of a DTAU
Dialog "An operational routine that uses commands to automate system functions; for example
Digital channel A transmission channel that carries signals in digital form.
Digital cross-connect system (DCS) "A sophisticated digital switch. It can switch an entire T1 line
Digital Data Services (DDS) "A 56- or 64-kbps digital channel that provides private line
Digital loop carrier (DLC) A digital transmission system designed for subscriber loop plant. Multiplexes a plurality of circuits onto very few wires or onto a single fiber pair.
Digital Remote Test Unit (DRTU) "The Hekimian 6700 test system that provides complete monitoring and testing capabilities for digital circuits (DDS
Digital serving area (DSA) "The combined geographical serving areas of a set of DDS serving offices. The appropriate tariff(s) specifies this area. The DDS office serving areas that make up a DSA are not necessarily continuous. Also
Digital signal A signal that has a limited number of discrete states before transmission.
Digital Signal at Level 1 See DS1
Digital Signal at Level 3 See DS3
Digital system cross-connect (DSX) "An internal interface that acts as a central point for cross-connecting
Digital Test Access System (DTAS) Hekimian's family of digital access and test equipment.
Digital Test Access Unit (DTAU) A subset of digital access and test equipment included in Hekimian's DTAS product line. This equipment provides split and hitless monitor access to T1 lines for maintenance and testing.
Digital Test Access Unit Plus (DTAU+) A subset of digital access and test equipment included in Hekimian's DTAS product line. This equipment provides hitless access to T1 lines in both the monitor and split modes.
Digroup (digital group) A basic group of PCM channels assembled by time division multiplexing (TDM). Usually derived from 1.544-Mbps PCM-multiplex equipment.
Distributed Sniffer System (R) A network of analyzers remotely controlled from a number of hosts and/or workstations.
DLCI Data Link Connection Identifier
DMI Data Mode Idle
DMS Digital Multiplex System
DMT Discrete Multitone (modulation)
DN Directory Number or Distribution Network
DNS Domain Name System
DNS Server A computer that translates a host into a network address so the table of names and addresses does not have be stored in each host.
DNT Do Not Test
DO Drop Out
DPMU Hekimian's 3249 Digital Performance Monitoring Unit
DPT Distributed Physical Test
DPU See DS1 Performance Unit.
DS0 Digital signal at the 0 level. A BPNRZ signal at the 64-kbps rate.
DS0-DP Digital Signal at 0-level Data Port channel unit. A plug-in circuit pack that recovers a DS0 signal for further connections. Its input and output signals are at 64 kbps.
DS0A "A DS0 signal that carries data for only one customer. For subrates
DS0B "A DS0 signal that is the same as a DS0A signal when carrying 56-kbps customer data. However
DS1 Digital Signal at Level 1
DS1 (Digital Signal at Level 1) "A digital transmission format in which 24 voice channels are multiplexed into one 1.544 Mbps (USA) T1 digital channel or
DS1 framing errors Frame synchronization bit errors detected by the Model 6302 DTU in either terminal framing (Ft) or signaling framing (Fs) bits.
DS1 Performance Unit (DPU) The Hekimian 6301 test set that provides complete in-service monitoring. This test set also provides out-of-service testing of DS1 signals.
DS1 Signal Access Unit (DSAU) "A plug-in circuit pack used in DDS hub offices. This unit provides full duplex access to a DS1 signal
DS3 (Digital Signal at Level 3) A digital transmission format in which 28 DS1 signals are carried on a T3 facility at a rate of 44.736 Mbps or on an E3 (CEPT) facility at a rate of 34.368 Mbps.
DS3 Frame A group of bits sent serially over a communications channel (or facility). A DS3 frame consists of 56 blocks of data; each block contains 84 bits of information prefixed by one overhead (framing) bit. The overhead bit has a variety of uses.
DS3 Idle Signal A framed signal with a …1100…payload pattern transmitted when the terminal (or network element) equipment is inactive. Frequently used as the DS3 keep-alive signal for network test resources.
DS3 Test Unit The Hekimian 6305 test set that provides complete monitoring and testing capabilities for in-service and out-of-service DS3 circuits.
DSE Data Switching Exchange
DSLAM Digital Subscriber Line Access Multiplexer
DSP Display System Protocol or Digital Signal Processor
DST Data Station Termination
DTCI Digital Trunk Carrier Interface
DTMF See Dual-tone Multifrequency.
DTR Data Terminal Ready
Dual-tone multifrequency (DTMF) "Signaling that uses a simultaneous combination of a lower and higher group of frequencies to represent each digit or character. The lower tones are 697
Duplex A facility which permits transmission in both directions simultaneously. Also called full-duplex.
Duty cycle "The percent of a single pulse period (for a ""1"") during which the voltage is nonzero. The ratio between actual pulse width and the total available time slot."
DX signaling "A long-range
 

 

Outside Plant
Pole Climbing Pole Climbing
Pole Top Rescue /1st Aid/CPR Cert Pole Top Rescue /1st Aid/CPR Cert
OSHA Confined Space OSHA Confined Space
OSP Bonds & Grounds OSP Bonds & Grounds
Telephone I & R Telephone I & R
Noise Mitigation Noise Mitigation
Copper Splicing Copper Splicing
OSP Tester, Fault Loc... OSP Tester, Fault Loc...
DSL - IMT DSL - IMT
T1 & T3 T1 & T3
T1 Spans & HDSL T1 Spans & HDSL
Adv. OSP/DSL Field Adv. OSP/DSL Field
Special Circuits Special Circuits
OSP Fault - I&R OSP Fault - I&R
IPTV Intallers IPTV Intallers
Fiber Optics -ER Fiber Optics -ER
CO Bonds & Grounds CO Bonds & Grounds
Utility Locating Utility Locating
Fiber Optics-Industry Apps Fiber Optics-Industry Apps
xDSL xDSL
IPTV for Telecos IPTV for Telecos
Cat 5-6-7 Cert Cat 5-6-7 Cert
MetroE Field-Tech MetroE Field-Tech
Air Pressure Air Pressure
Air Dryer Air Dryer
Click Here For More Courses
Central Office
CO Bonds & Grounds CO Bonds & Grounds
CO Power CO Power
CO IMTR CO IMTR
SONET/SDH SONET/SDH
ISDN ISDN
Frame Relay Frame Relay
SS7 SS7
DDS DDS
Internetworking ATM Internetworking ATM
DWDM/Routing DWDM/Routing
DMS10 DMS10
DMS100 DMS100
MetroE Field-Tech MetroE Field-Tech
T1 & T3 T1 & T3
T1T3 for CATV T1T3 for CATV
Special Circuits Special Circuits
CS 1500 Centrex CS 1500 Centrex
VoIP/Data-Voice VoIP/Data-Voice
BGP BGP
Nortel/Norstar CallPilot Nortel/Norstar CallPilot
Nortel BCM50 Nortel BCM50
Metro Eternet Metro Eternet
Digital TV Crossover Digital TV Crossover
Click Here For More Courses
Fiber Optics
Und. Fiber Und. Fiber
Fiber ISP/OSP Combo Fiber ISP/OSP Combo
Hands-On FTTH Hands-On FTTH
Fiber Management Fiber Management
Fiber WAN/Storage Fiber WAN/Storage
Fiber Adv. Testing Fiber Adv. Testing
Fiber Optics Adv. Splicing Fiber Optics Adv. Splicing
Fiber Optic - ISP/LANs Fiber Optic - ISP/LANs
Fiber Optics -ER Fiber Optics -ER
Adv Fiber Optics Adv Fiber Optics
FTTH-NGN FTTH-NGN
Fiber Optics-Industry Apps Fiber Optics-Industry Apps
Click Here For More Courses
IT/Networking
Internetworking Essentials Internetworking Essentials
Adv. Internetworking Adv. Internetworking
Network+ Network+
A+ Cert A+ Cert
Gigabit Networks Gigabit Networks
SONET/SDH SONET/SDH
CCNA BootCamp CCNA BootCamp
TCP/IP TCP/IP
SNMP SNMP
Bridges, Routers & Switches Bridges, Routers & Switches
Network Management Network Management
Advanced Networking Advanced Networking
Cisco Simplified Cisco Simplified
Metro Eternet Metro Eternet
FTTH-NGN FTTH-NGN
IP-CAST IP-CAST
CS 1500 Centrex CS 1500 Centrex
Digital TV Crossover Digital TV Crossover
LTE-In Depth LTE-In Depth
LTE Core LTE Core
LTE Air Interface LTE Air Interface
LTE and 4G LTE and 4G
LTE Charging Mgmt and Apps LTE Charging Mgmt and Apps
Mobile Detection Mobile Detection
Carrier Wireless Carrier Wireless
VoIP/Data-Voice VoIP/Data-Voice
VMware View VMware View
Click Here For More Courses
Energy / Power / Safety
OSHA Confined Space OSHA Confined Space
Ladder Safety and Fall Protect Ladder Safety and Fall Protect
Mine Safety Mine Safety
Voltage Cable Splicing Voltage Cable Splicing
Elec Transformer Elec Transformer
Power Quality Power Quality
Substation Testing Substation Testing
Elec Testing Elec Testing
Click Here For More Courses
Certification Courses
CCNT - Cert CCNT - Cert
CTP Prep CTP Prep
Network+ Network+
A+ Cert A+ Cert
CCNA BootCamp CCNA BootCamp
MCSA-Core-1 MCSA-Core-1
Fiber ISP/OSP Combo Fiber ISP/OSP Combo
Click Here For More Courses
Additional Courses
TeleCom Mgmt TeleCom Mgmt
TeleCom Tech TeleCom Tech
Emerging Tech Emerging Tech
Understanding IPTV Understanding IPTV
IPTV for Telecos IPTV for Telecos
IPTV Tech IPTV Tech
TelCom Network Testing TelCom Network Testing
TeleCom 1 TeleCom 1
TeleCom 2 TeleCom 2
Nortel CS1000 Nortel CS1000
NARS/BARS NARS/BARS
Nortel/Norstar CallPilot Nortel/Norstar CallPilot
Metro Eternet Metro Eternet
CallPilot User/Sys Admin CallPilot User/Sys Admin
CallPilot Basic Admin CallPilot Basic Admin
CS1000 End User CS1000 End User
CS1000 & TM CS1000 & TM
Nortel/Norstar MICS Nortel/Norstar MICS
Nortel CallPilot Nortel CallPilot
IPTV Intallers IPTV Intallers
Fiber Optics-Industry Apps Fiber Optics-Industry Apps
CS 1500 Centrex CS 1500 Centrex
Digital TV Crossover Digital TV Crossover
LTE-In Depth LTE-In Depth
LTE Core LTE Core
LTE Air Interface LTE Air Interface
LTE and 4G LTE and 4G
LTE Charging Mgmt and Apps LTE Charging Mgmt and Apps
Mobile Detection Mobile Detection
VMware View VMware View
Click Here For More Courses
 

BTS Offfers BICSI CECs
BTS offers BICSI CECs for most of our courses. You can find out more information about our BICSI CECs by clicking here.

Copyright Information
Product names mentioned herein may be trademarks/servicemarks or registered trademarks/servicemarks of their respective companies and are hereby acknowledged. All product names that are known to be trademarks or service marks have been appropriately capitalized. Use of the name BTS, inc./the url: www.btstraining.com is for identification purposes only, and should not be regarded as affecting the validity of any trademark or service mark, or as suggesting any affiliation between BTS, Inc. and the trademark/servicemark proprietor.