APPENDIX 5
Glossary of Terms
ADSL
Asynchronous Digital Subscriber Line
A ‘wideband’ digital communication service from a network provider to a
subscriber that carries a high volume of digital data, most commonly for
internet access. Sometimes called ‘Broadband’. An ADSL service is often
provided with a simultaneous analogue PSTN service on a Hybrid line.
Alarm Abort
A facility to reduce false alarms requiring police response. Specified by ACPO
(The Association of Chief Police Officers) in UK. An Alarm Abort situation
occurs when the alarm system is set, and an alarm occurs, and then it is
reset by the alarm system being unset by a key or valid user code, all within
90 seconds.
This false alarm is often caused by the user of an alarm system failing to set
the system correctly. The Alarm Abort signal identifies this situation to the
ARC thus avoiding an unnecessary police visit to the site.
Analogue PSTN
Analogue Public Switched Telephone Network.
The analogue national telephone system. Often just called the PSTN. Serv-
ice is available to customers on twisted-pair wires that carries a DC supply
provided from the network telephone exchange.
ARC
Alarm Receiving Centre
A 24 hour manned centre (often privately owned & operated) capable of
receiving & logging calls of alarm and forwarding them to security authorities
and other relevant services. Often called a Central Station.
Broadband
See ADSL
Call Minder
A call answering service offered by some telecom Service Providers. When
an incomming call to the subscriber’s telephone is not answered, then the
Service Provider can record it and forward it to the subscriber at a later time.
Central Station
See ARC
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