How Does a Security System Communicate?

Types of Communication Include:

  • Basic Phone Line Dialing
  • Cellular Communicator
  • IP Communicator

Phone Line Communicator

The most common and basic communications are signals sent to the central station via a telephone line at the site. The control panel picks up the phone, dials the phone number for the central station, and transmits codes that are interpreted by software and operators. Nearly all models have a built in dialer for phone line communications. This form is usually the least expensive and reliable as phone lines are quite stable. Several drawbacks do exist, however.

Phone lines can be cut outside the home by a clever burglar. Once the phone line is removed, the security system's monitoring is disabled. Although it still sounds the siren on an intrusion, it cannot transmit signals leading to a dispatch. Special housings and metal conduit can be installed at the outside phone connections to combat this or an additional form of communication can be installed.

An additional concern is the new wave of VOIP phone lines. Many of these services do not support fax machines or alarm panel communications. As a customer changing service from a standard phone line, you should contact you alarm service company and confirm support for the phone service you are interested in. Phone service offered through AT&T UVerse, Verizon FIOS, and most cable companies support most newer panels. Communications are often not possible through companies such as Vonnage and Magicjack. As a guildeline, if the service claims to support faxing, there is a good chance the alarm can communicate as well.

Cellular Communicators


A cellular communicator is a device that transmits signals from the security system to the central station using the cellular network. These are sometimes confused with a "wireless system" but this communicator is most often referred to as a cell backup. The cell unit is a separate component often installed near the control panel. Installed as a backup, the communications can use phone lines or cellular to ensure a signal is transmitted. Installed as a primary communicator, no phone line is required at the site. Most have their own battery backup and are immune to power failure and phone line cut.

Pricing is normally a little higher for a system that uses cellular communications. The unit itself has some initial cost and monitoring is usually around ten dollars extra per month. Often, the unit cost can be waived depending on the terms of the monitoring agreement.

IP Communicators

An IP communicator allows the control panel to transmit signals to the central station using the internet. A separate component is normally required to set this up, however, some new control panels are beginning to include IP communication capability.

Remote access is also available to control your system using the web or handheld devices, sush as an iPhone. Virtual access to the alarm may raise monthly monitoring, though, usually very little. Please Contact Us for current availability and pricing.