Your Security System and Digital Phone or Voice over Internet Protocol (VoIP)

Your security system communicates to the central station by a digital communicator. The protocol for the communicator
was designed in the 1960s. The basic operation is to electronically create a phone off hook,dial a number and communicate to
a digital receiver at the central station. This protocol was designed when the only phone service provider was AT&T.

It was designed to use the existing technology of the times. The original communications rate was 20 Baud . A distinct tone was given
for each pulse,and multiple pulses were given for each digit. If you listened to a typical transmission of a burglar alarm you would
hear pulsed tones and pauses. An example: six tones, a pause, four tones, a pause, three tones a pause and three tones(account 643 alarm
code 3). This transmission would be repeated. The receiver would decide if the two transmissions matched. If so then it sent a hang up signal,
and the alarm information was printed on a tape for operator action.

Since the original design several reporting formats have been created, the speed has increased to 1200 baud. Computers have
replaced the printer and considerably more information is sent. The basic premise is still the same. A number is dialed, a receiver
answers and the alarm communicator sends audible information in the form of tones or digital pulses. The format is designed for analogue
phone systems.

Digital communication is not designed for Time Warner Digital Phone or any of the various VoIP telephone providers.



A number of 3C customers have switched from the traditional telephone provider to Digital Phone and VoIP.
The structured wiring centers (Home Director and OnQ) installed in homes since 1998 for telephone and cable within the
home make this conversion very easy (click here for detailed instructions).
We insist you test the alarm system and the central station reporting as soon as you convert your phone service.
If the test result is your alarm system reliably reports to the central station, we do not guarantee it will continue to do so.

Is the modem secure from cable disconnection?
Neither Digital Phone nor VoIP providers promise continuous reliability.
Both of these systems require continuous electrical service in your home to operate properly.
Is the modem connected to a Uninterruptible Power Supply (UPS)?
Conventional telephone service does not require connection to household electrical sources.
Both of these systems convert standard, analogue, voice information into digital packet information.
It must be properly decoded with the correct tones and pauses for alarm reporting to be interpreted by the
central station receiver.

Check with your provider to see if they will guarantee this decoding.
Since we install smoke detectors in almost every security system, reliable alarm reporting is potentially a life safety issue.
Of course digital communication is not the only available form of alarm reporting. Alarm signals can also be sent to the central
station by radio, cell phone network (celemetry), and broadband. Most of the systems installed by 3C Systems since 1994 can have
celemetry reporting added. Radio and broadband reporting require system upgrades.
Please call or email for more information.

Jim Hurdis
919.469.5021 President - 3C Systems, Ltd.
hurdis@3csystems.com


Other Alarm Reporting Options

Celemetry Reporting
Broadband Reporting