Even experts need occasional help with telecom terms. We have combined glossaries from several sources to simplify finding the definitions you need.
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2B1Q (Two Binary, One Quaternary)
See Two Binary, One Quaternary.
Two-wire loops support loop-start, ground-start, loop reverse-battery or customer-provided inband signaling. 2-wire Digital loops are a Verizon Wholesale Unbundled Loop service and provide a digital 2-wire enhanced channel. Learn more.
Four-wire loops support duplex signaling in addition to all of the same capabilities as 2-wire loops. 4-wire Digital loops are a Verizon Wholesale Unbundled Loop service and provide a digital 4-wire enhanced channel. Learn more.
A digital central office switching system made by Lucent, typically used to serve local subscribers.
500 Access Service
Telephone service using a non-geographic area code that allows the customer to define a sequence of telephone numbers for forwarding calls to him.
See 500 Access Service.
The fastest modem speed supported by a dial up modem.
The standard speed for a DDS private line digital service.
800 Database Access Service
A Verizon Wholesale service offering that identifies and routes toll free 800-type long distance calls originating from end users to the appropriate 800 service provider. Learn more.
800 Number Portability
Allows an end user to retain a given 800 telephone number when changing to another long distance carrier.
Also known as 'WATS' service (Wide Area Telecommunications Service), uses 800 or 888 as prefix and provides toll free service to the user dialing the number.
A universal telephone number that gives the public direct access to the Public Safety Answering Point for emergency calls. Basic 911 service collects 9-1-1 calls from one or more local exchange switches that serve a geographic area, and sends each call to the appropriate designated authority. Also known as E-911 service. Learn more.