[asterisk-users] alarm POTS lines

Sat Dec 4 09:55:35 CST 2010

jon pounder wrote:
> On 12/04/2010 03:01 AM, Tammy A Wisdom wrote:
>    
>> You all do know that this is something you could be sued for since this is 'life safety equipment' ?  I've heard from multiple sources that if it isn't against the nfpa that it will be very soon
>> Ask yourself if you want to be subject to a lawsuit if someones house is robbed, someone dies, house/business burns down and the alarm panel is unable to communicate?  Ask your insurance rep if they will cover you doing this type of voip stuff and they'll most likely tell you not too. Bottom line is this is NOT a smart thing to put on voip.
>> Tammy
>>
>> Tammy A Wisdom
>> Summit Open Source Development Group
>>
>>      
> nfpa only applies where nfpa is actually a requirement, ANYTHING anyone
> does that is not required (residential fire and burglar alarm) is better
> than the alternative of nothing at all. Calling yourself a ulc certified
> monitoring center or something like that is a no no if you don't meet
> those requirements, but selling a service as what it is, is perfectly
> fine, if you are not guaranteeing something you can't provide you are in
> the clear.
>
>    
You want to bet your business and liability insurance on that position?

Anyone considering this direction had better run it by their business 
insurance risk management department, and a good lawyer versed in laws 
involved in the state(s) involved.
> All that aside things are moving to direct tcp/ip communication, using
> voip to talk to antiquated monitoring equipment is just an interim fix
> as the consumer end technology is moving faster than the central station
> technology. The argument voip is unreliable compared to pots really is
> not true if everything is setup properly. tcp/ip and anything that lives
> on top of that protocol like voip etc., has much more flexible routing
> and failover than any pots circuit could ever hope to have, and can use
> multiple independant paths for communication, and the connection can be
> held open like a dvacs circuit for continuous monitoring without all the
> overhead of individual copper pairs and multiplexers at the monitoring
> center.  Its hard for the manufacturers of this equipment to stomach
> though that a pc with a network card is actually more functional than a
> multimillion dollar piece of hardware they used to sell, so change is
> slow coming.
>
>    
VOIP is NOT yet as reliable as a POTS circuit. The degree of 
unreliability depends on the providers involved, but network managers 
have yet to put into place It certainly is getting somewhat better, and 
one can skew the statistics with the volume of data involved, but when 
life safety issues are involved, it isn't there yet. Even Mobile ( radio 
) backup is considered secondary for reporting, and then not for 
fire/sprinkler systems.

the safest circuit for monitoring, though seldom available anymore, is 
the supervised loop to the monitoring station.
A PC with it's inherent frailty is way down the list in terms of reliability

John Novack
>
>
>    
>> -----Original Message-----
>> From: Ryan Wagoner<rswagoner at gmail.com>
>> Sender: asterisk-users-bounces at lists.digium.com
>> Date: Sat, 4 Dec 2010 00:03:25
>> To: Asterisk Users Mailing List - Non-Commercial Discussion<asterisk-users at lists.digium.com>
>> Reply-To: Asterisk Users Mailing List - Non-Commercial Discussion
>> 	<asterisk-users at lists.digium.com>
>> Subject: Re: [asterisk-users] alarm POTS lines
>>
>> On Thu, Dec 2, 2010 at 11:58 AM, Jeff LaCoursiere<jeff at sunfone.com>   wrote:
>>
>>      
>>> Hi,
>>>
>>> I've brought this up in the past and there was a good discussion - am
>>> wondering if there have been any new developments.
>>>
>>> Our dialtone service, like I am sure is true for most ITSPs, touts the
>>> ability to drop your POTs lines for significant savings.  For businesses
>>> we have a low-cost Atom based PBX and a "fax relay" setup locally with
>>> hylafax/iaxmodem to solve that issue, and it is working very well.  We
>>> don't however, have a solution for their alarm lines.
>>>
>>> The problem is of course that modem calls over VoIP are flaky at best.
>>> Even though these alarm calls are low baud rate, when we test with the
>>> alarm company we only pass about 30% of the time (ulaw from customer site
>>> to our central switch, then out a T1).  To be fair there is no QoS on
>>> their Internet links yet, and that certainly plays a role.
>>>
>>> But it seems to me that there should be a solution much like our "fax
>>> relay", where we literally accept the fax call over the local LAN, produce
>>> a PDF file, transfer it to the central switch which then dials it back out
>>> over a T1.  In that case the only "modem over VoIP" is on their local LAN,
>>> which has performed well for us.
>>>
>>> I would love to see a DSP "modem" that could answer an asterisk channel,
>>> send the data stream over TCP to some remote asterisk, which could then
>>> "relay" the stream by making an outbound DSP modem call on a PSTN trunk.
>>> Has anyone attempted anything like this?
>>>
>>> As an aside, since the recent thread on Seagate Dockstar installs, I have
>>> several running.  This would be the perfect platform for the "relay" on
>>> the customer end, being so ridiculously cheap (I bought three for $30
>>> each, plus 3 $10 4G USB sticks).
>>>
>>> So hoping this will spark some comments on the concept in general, and
>>> really hoping someone has actually tackled something similar.  It could
>>> open up a nice niche for even residential customers with expensive POTS
>>> lines dedicated to alarm systems.
>>>
>>> Cheers,
>>>
>>>
>>> --
>>>
>>> Jeff LaCoursiere
>>> SunFone
>>> jeff at sunfone.com
>>>
>>>
>>>        
>> Alarm panel communication, at least with Ademco, is done only with
>> DTMF. When I tested the Asterisk AlarmReceiver application I found
>> that the DTMF tones were so short they weren't always recognized by my
>> ATA in RFC 2833 mode. Changing it to inband DTMF worked better, but
>> then I was having issues with the AlarmReceiver application.  Have a
>> look at the below link, which touches on alarm panel communicates.
>>
>> http://www.voip-info.org/wiki/view/Asterisk+cmd+AlarmReceiver
>>
>> Since the communication is done with short DTMF it only takes a few
>> seconds once the remote end answers to relay the message. This is not
>> the same as modem communication when sending a fax.
>>
>> At least for alarm communication the solution would be an ATA that can
>> correctly recognize and translate the DTMF to RFC 2833. Then it is up
>> to the remote end to correctly translate this back to DTMF to send
>> over the T1. The below link explains the different DTMF modes
>> supported by Asterisk.
>>
>> http://www.voip-info.org/wiki/view/Asterisk+sip+dtmfmode
>>
>> Ryan
>>
>>
>>      
>
>    

-- 

Dog is my Co-pilot