Re: AlarmNet reliability how can it go down with no notice?

[Nomen Nescio <nobody@xxxxxxxxx>]

>I made an assumption that my radio sent some kind of watch dog signal
>to the central station every 10 minutes so they can make sure the
>network is functioning. This is not the case, apparently. My call
>center stays completely unaware when AlarmNet has any failure. This
>has me very worried. I can no longer depend on the network at all.
>
>Can anyone explain how AlarmNet works? There is no explination on
>their website. The alarm companies don't seem to want to share with me
>any technical details about how AlarmNet works. My position is that
>the proper thing to do is to have each node on the network send a
>short packet of data like [STX]station ID,Ready[ETX] every 10 minutes.
>The load on the network would be minimal. We're talking less than 100
>bytes of data multiplied by 50K or so radio sets: less than 50 megs of
>data in 10 minutes. That works out to a loafing 10Kpbs throughput. The
>call center would then know in ten minutes that my radio was no longer
>communicating with the call center. The call center could then take
>steps to find out why and notify me that something is wrong with my
>system. Therefore, even though radio networks are not 100% reliable,
>at least I can be 100% confidant that when my alarm system is armed, I
>will know quickly when or if there is a problem.

First of all, there are different types of Alarmnet service.  You probably
have Alarmnet-C or Alarmnet-GSM service; more on these in a moment. There
is also Alarmnet-M service, which can be programmed to detect a loss of
radio communication within six minutes, and which you will pay dearly for.
And, in some large cities, there is Alarmnet-A service.  Alarmnet-I is an
Internet reporting system, not a radio system, that can also detect a loss
of communication within minutes.

Alarmnet had a problem:  it wanted to sell radio alarm service nationwide,
without having to build and maintain its own nationwide radio network.  The
solution was to use the control channels of the cellular telephone network,
which of course they have to pay for.  This gives a big radio network at
little cost, one that is maintained by someone else.  Through an
arrangement with the cellular companies, alarm signals are sent back to
Alarmnet in New York, which then sends them on to the appropriate central
station by various means.

These Alarmnet-C and -GSM radios are designed to be reasonably affordable,
and to impose a minimum amount of overhead on the cellular providers'
networks.  The monthly fee also reflects the low network traffic.  Alarmnet
is supposed to be releasing a version of the GSM radios soon that will do
frequent polling, however I expect Alarmnet's monthly fee for that service
will probably be more than you are paying for your monitoring today.   Your
central station will also charge a higher monthly fee for having to deal
with the occasional temporary loss of radio communications -- often just
long enough to be annoying, and perhaps, to call you.

The Alarmnet-C service is based on analog cell technology, which will be
going away soon.  The  GSM radios are what Alarmnet is promoting most
heavily at the moment.

Alarmnet already offers a combination Internet communicator and GSM radio
called the 7845-iGSM.  This does not provide the five minute supervision of
the true Internet communicators, but it does provide alarm reporting by
Internet, GSM radio, and SMS radio if the other two fail.  It's something
to discuss with your alarm service provider, as it's more secure than what
you have now.

- badenov