To our customers regarding various phone services and Alarm Monitoring

There are many mixed messages regarding Verizon FiOS and Optimum voice services and how they work with alarm monitoring. We at GSI have taken the time to research what both companies have stated in writing and you can read it for yourself below:

Verizon – FiOS

(From:, fine print at bottom of screen in FiOS section)

Verizon will install a battery back-up unit inside your garage or home. A 3-pronged grounded power outlet should be available nearby for the battery back-up unit. You are responsible for periodically replacing the backup battery. A battery unit will supply back-up power for standard voice service (but not Voice Over IP services), including E-911, for up to 8 hours. Backup battery does not supply power for Internet, VOIP, or video services. Not all Alarms (switch or private line), are compatible with fiber. A customer wanting a response activated alarm system should check with their specific alarm company for guidelines. It may be necessary to maintain/install a separate copper line into the home to support alarm service.

Cablevision – Optimum Voice

(From: Optimum Reference Guide)
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Customers who use Optimum Voice as a connection between their home security system and central station monitoring are responsible for testing their system with their alarm company at the time of installation and on an ongoing basis, and also must notify their alarm company of any change in their telephone number.

Cablevision does not support the use of any Optimum Voice service as a connection for emergency medical alert systems, high-security monitoring systems (UL 681 or similar) or fire alarm systems (UL 864 or similar). Customers must maintain alternate phone connection for such connections. We will provide a wire connection so that Optimum Voice services are available for use with your existing security system. Customer must follow-up with their alarm company to confirm that they have your correct and current phone number and to perform any periodic operational tests that your central station-monitoring provider might recommend. In the event of an outage, your Optimum Voice service will not be available to contact your central station-monitoring provider.

Based on the above, you can see that they have taken the stance that the customer must check with their alarm company for standard monitoring. Verizon says that they will install a battery backup that will support the voice service portion only for up to 8 hours. (Just for the record FiOS voice is NOT VoIP, it looks like and behaves like a POTS line but it is not powered from the Central Office as a traditional copper phone line). Cablevision actually goes further to say that they DO NOT support “emergency medical alert systems, high-security monitoring systems (UL 681 or similar) or fire alarm systems (UL 864 or similar)”.

Putting aside what we all know about code compliance and what is allowed by NFPA or any other standard, the service providers themselves are telling you not to use their service for critical monitoring applications. They are also deferring back to the alarm companies to determine if their service is acceptable for non-critical, or standard monitoring services.