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Alarm Systems and Telephone Transmission

The history of the security alarm industry is really quite interesting, starting with stand-alone alarm systems that when activated sounded an alarm to signal that something was wrong. These original security alarms were made up of bells or ringers when activated sounded the call for help. A security alarm is a system designed to detect intrusion – unauthorized entry – into a building or other area. Security alarms are used in residential, commercial, industrial, and military properties for protection against burglary (theft) or property damage, as well as personal protection against intruders. Business security alarms were first put into use back in the 1800’s to denote unauthorized entry, intrusion or to warn that a fire was taking place signaling for help, security, police or after-hours night watchmen. As technology developed so did the security alarm warning system and with the invention of the telephone, alarms were now capable of  being transmitting over what has become known as a POTS line (plain old telephone) service. POTS lines were very reliable because they did not run on electricity but instead a telephone company central office with a low-voltage battery generating enough current for the phones to operate even when the electric wires were cut or out. POTS technology was actually an analog telephone line and was part of the PSTN (Public Switched Telephone Network).  POTS used circuit-switched technology and it’s served the alarm industry well for many years as the security warning device alarm systems were then designed to communicate over the analog lines. The initial technology developed upon which POTS is built may not be the fastest at transmitting alarm data from an alarm panel to a UL-Listed monitoring station, but it has been undoubtedly the most fault-tolerant means of signal transport in existence, in technical terms.

Why was POTS Technology So Successful?

The reason for POTS’ technology success and its excellent track record is the fact that telephone companies have a sustainable source of backup power that includes a large bank of batteries and, sometimes, a gas-fired generator to recharge them when power begins to wane during extended blackout periods. This is why a traditional telephone company line or what we call an analog phone line, continues to work, providing a dial tone and communication well into a power outage of almost any duration in length. Public Utility Commissions (PUC) had varying regulations on a state by state basis requiring telephone companies to maintain power in the event the public electric utility failed. This ensured that telecommunications services were available at all times as a public safety requirement. As technology advanced so did the structure of telephone systems and their conversion from analog equipment into digital equipment. Additionally, this technological advancement that has taken place, this digital conversion has allowed telephone lines to communicate more than just voice but data as well. Circuit-switched based (analog) equipment has been in service for decades, but there is less and less demand for circuit-switched analog services as home and business owners opt for digital lines, cellular, cable and other means of broadband communications that use packet-switched technology (VoIP).  This new telephone company technology is more efficient and has a greater ROI (Return on Investment).  Because of the advent of this new technology, carriers are giving less and less attention to the upkeep of their current operating POTS networks.

AT&T, Verizon and other former Bell operating companies has long since been associated with telephones (since the early 1900’s). To some it came as a bit of a surprise when the giant telecoms petitioned the FCC in 2009 for permission to phase out their analog landline service by the year 2020. These communication giants understood that the cost of maintenance to keep these antiquated systems alive was too high and their networks and future systems being implemented were digital and cellular platforms.  It came as no surprise when the FCC agreed.

Since 2010, AT&T, Verizon and the other Telcom’s have been replacing their traditional copper wire-based service with fiber optic technology.

VOIP is short for Voice over Internet Protocol sometimes called Digital service. Voice over Internet Protocol is a category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls by sending voice data in packets using IP rather than by traditional circuit transmissions of the PSTN.

VOIP (Voice Over Internet Protocol) service is not a reliable communications path for alarm systems, the alarm control panels are designed to utilize POTS lines and will not operate properly on VOIP. Most VOIP interfaces and modems do not have battery backup so if the power is out so are your communications.

ESI as Your First Choice for Security Alarm Systems

ESI, Emergency Systems, Inc. has been resolving these problems for over 20 years by utilizing a cellular type of alarm communicator to send alarm information to our monitoring center.   We now offer IP coupled with cellular which provides a fast, reliable and economical communications path and is offered at a lower cost than the analog phone lines. ESI is a commercial, industrial and high-end residential security company with almost 40 years of continuous service to North Central and North Florida. If you would like to find out more about ESI’s superior Cellular / IP alarm communications. Give us a call (904) 388-3975 or visit our website at for a complete list of our services and credentials. Our highly trained and experienced security technicians will be glad to give you a no-obligation estimate of how to increase your security shield and partner with one of the industries security leaders. ESI.