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SEM Security Systems
a division of Southeast Mobility Inc
In order for your alarm system to notify the police that someone has broken into your home it must be able to communicate. In years passed that has been done over the premise telephone lines. Today there are other technologies available and as a matter of fact, phones lines are going to soon become of thing of the past for alarm communications. A lot of customers are doing away with their home phone lines and relying strictly on their cell phones. We'll look at those other technologies in a minute but first let me clarify something about how your alarm system communicates your alarm over your phone line.

The panel is connected to the phone line, the wire is run from the box on the outside of your building to the panel and then another set of wires goes back to the box and is connected to the wires that are coming into your home or business. When an alarm occurs, the panel picks up the phone line and makes a call just as you do when you make a call. I've had people argue with me that the monitoring center will know it immediately if someone cuts the phone line on their alarm system. In a word, NOT. If your system is on a bank, large jewelry store or other high risk application, you alarm system may be attached to a full time dedicated data line that is in constant communications with the monitoring computer. If that line gets cut then the computer knows that it has lost communications with the panel and it will create an alarm that the operator will dispatch the police on. 99.9% of the alarm panels that are in operation today are attached to a standard plain ole telephone service line (POTS line) which picks up the line, dials a ten digit number, and then communicates to the monitoring computer, if the phone line gets cut, it haint calling no one folks.

Now that I have that off my chest, let's go back and talk about how that phone line is hooked to the panel. The wire runs from the box outside, to the panel then back to the box outside where it is hooked up to the wires that are coming inside the home or business, why is it wired that way? Have you ever been on the phone and had someone in the other room pick up a phone and start dialing? What happened? You heard the dialing in your ear but their call didn't go through, so what would happen if you were talking on your phone at home late one night and someone kicked in the back door? By running the wiring from the box outside through the panel then to the rest of the home, it enables the panel to take control of the line when needed. If you are on that line, your call will be cut off, the panel will complete it's call and then turn the line back over to you. If your alarm goes off and you hear dialing over the phone line, then it is not wired correctly and you should report it to your alarm company.

So why are POTS lines going to become a thing of the past? In a word, technology. That same wire that use to bring only a dial tone into your home can now be used to deliver telephone, television, and internet communications. This is done by using digital communications. Even if you still have a POTS line, your analog call may be converted to digital further down the line. Once your call arrives at the switching office it may be converted to digital and sent down the line with a hundred other calls simultaneously. At the next switching office, calls that don't need to go any further are picked off, converted back to analog and delivered to your other party on their POTS line. The problem as it relates to your alarm panel is in the conversion process. Your panel communicates with the monitoring computer by sending it a series of tones. When those tones are converted from analog to digital and then back to analog, the tones are often not accurately reproduced which makes it impossible for the monitoring computer to understand the message. Sometimes the message is completely garbled and sometimes it is misinterpreted and the monitoring computer will indicate an alarm at the wrong residence or maybe the correct residence but indicate the wrong zone.

To make matters worse, the Federal Communications Commission (FCC) has given the go ahead to the phone companies to set sunset dates on POTS lines beginning 2014. What this means is that the phone company has the right to notify you that your POTS line will no longer be serviced and you will have to convert to digital communications or no longer have telephone service.

So, what do we do about all of this. We can't stop progress so we have to get on the band wagon and start allowing our alarms to communicate digitally. We have a couple of alternatives, an IP communicator or a cellular communicator.

The IP communicator is simply an interface device that is added to your alarm system that allows your panel to communicate over your internet directly to the monitoring computer, and it is quick. The typical alarm report over a POTS line takes about 12 to 18 seconds. That is from the time the alarm sounds until the operator has the information on the screen to process. With an IP communicator that time is reduced to 2 seconds. Our customers who have IP communicators regularly report that their phone is ringing before they can get their code punched in to turn the alarm off. What are the draw backs? Well, you are still communicating, in most cases, over a phone line or cable wire which is accessible outside the home and therefore is subject to be cut by the would be burglar. If your internet goes down, your panel can't communicate. This means that you will need to add a battery backup to your cable or dsl modem so that it will continue to function even if the ac power goes off.

The cellular communicator is another interface device that can be added to your alarm system that allows it to communicate to the monitoring computer via the cell phone network. It is self contained, battery backed up, and generally faster than a POTS line but not as quick as an IP communicator. Of course you will need cell phone coverage at your premise. Also, the unit is located inside the protected area making it difficult for a would be burglar reach it to disable it.

A few years from now these alternative forms of communications will become the rule rather than the "alternative", but for now the POTS line is the standard and therefore the alternatives come at an additional charge.