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[blu] (OT) Fwd: My take on E911 and VoIP



On Fri, 27 May 2005, Tom Horne <hornetd at mindspring.com> wrote:

> Now we get into this debate and some of the VOIP providers want to 
> blame us for not staffing administrative telephone numbers around the 
> clock thus giving them an inexpensive way out of the charges being 
> leveled against them. Those of you who are familiar with the 
> technology are even more aware than we are of the qualitative 
> difference between 911 service and any ten digit telephone number but 
> most of the public are not aware of those differences. Add to this the 
> fact that the VOIP providers are scared to death that they will be 
> required to provide 911 service at the first exchange rather than at 
> their offices hundreds or thousands of miles away and you have us 
> drawing and sharpening our public relations knives quite ready to leap 
> down the throat of anyone who tries to shift the blame for the recent 
> communications failures onto us.


Ben Jackson wrote:

> Errrr... I am pretty sure that every PSAP (Public Service 
> AnsweringPoint - 911 center, Fire/Police station, State Police, 
> anyplace that is capable of handling E911 calls) has some form of 10 
> digit number that routes to the E911 system. I've heard of clueful 
> people that have been programming their VoIP phones' various 
> 'emergency buttons' with said numbers. While it would have been smart 
> for VoIP companies to have these numbers, they are kind of secret 
> (Why? $DEITY knows. Probably the same reason LECs keep payphone 
> numbers secret) and most people don't know about it. (Heck, I didn't 
> either until this whole mess started).
>
> Now, the problem with VoIP is that there is NO 'first exchange' in the 
> sense that people are used to. When I dial out on my Asterisk box, it 
> zips out of my router, through the vast expanse of the Internet and 
> then gets onto the PSTN somwhere in Michigan. If 911 was done on the 
> 'first exchange' I'd probably get a sherriff's dispatch center 
> somewhere in Michigan. Even if they could help, the response time 
> would be horrendous. ;)
>
> The recent communications failures are equally to blame on the 
> consumer and the ILEC. The consumer is at fault for not reading the 
> fine print, and the ILEC is at fault for not having some kind of 
> "basic E911" service for every wirepair out there. I highly doubt how 
> ANYONE could blame public safety in this mess, and the VoIP providers 
> have done a very nice CYA job on their contracts.
>
> ~Ben

Ben
I'm not clear what you mean by "every PSAP (Public Service Answering 
Point - 911 center, Fire/Police station, State Police, anyplace that is 
capable of handling E911 calls) has some form of 10 digit number that 
routes to the E911 system."  I don't have exhaustive experience but the 
two PSAPs I have worked in did not in fact have a ten digit number that 
provided Automatic Location Information (ALI) or either of it's 
predecessors, Automatic Number Identification (ANI), or line seizure and 
ring back.  Please note that ANI is a totally different animal than 
caller ID and delivering ANI information over a POTS line is just not 
possible. They can only deliver CLID (Calling party IDentification), 
which is not provided when the calling subscriber has a "Non-listed" 
number.  One example of that difference is that unlike caller ID the 
caller has no control over whether the recipient gets the number and I 
mean none.  If the billing registers have the number then the PSAP will 
have it.  Those of you who have  worked in telephone provision know that 
one of the hard and fast rules of public utilities is no billing equals 
no service.  My position is that if the VOIP carriers need E911 
integration then all of the cost of providing it should fall on them and 
only them.  The LECs already have a system that works.  It's called 
911.  Here's the catch: VoIP providers want to provide _ANI_ info over 
the _CLID_ path, and say that it's "just as good" as E911. Of course, 
this ignores the fact that PSAPs are custom built and designed to work 
with their associated tandems, and that the E911 Name and Address 
database is totally separate from the regular phone company "Caller ID 
With Name" database.

As to why the ten digit administrative numbers of the PSAPs, that 
actually terminate on an appearance on a call takers console, are 
unlisted and confidential; the entire operation of a PSAP is predicated 
on the calls coming in on 911 with ALI.  The system of ranking the calls 
for dispatch is based on a triage process that assigns a priority to 
each call based on pre-identified criteria.  In order for that ranking 
to be assigned the caller must first talk to a PSAP call taker.  The 
order in which the various appearances on that call takers console are 
answered is 911, Public street emergency telephone call boxes (in the 
very few places were they are used),  Medical alarm ring down lines,  
Automatic fire alarm ring down lines,  hold up alarm ring down lines,  
emergency response facility ring down or Centrex lines, Published ten 
digit non emergency numbers if any,  and unlisted ten digit POTS 
administrative lines.  Ring down lines from alarm services that handle 
multiple types of calls that have not been provided with the equipment 
to indicate which type of call that alarm bureau is trying to relay are 
answered on the lowest call rank that tie line is used to relay.  UL 
listed class A alarm receiving stations use multiple tie lines or 
priority indicating tie lines.  UL listed class B alarm receiving 
stations use non-indicating lines.

 From my earliest days in the fire and rescue service I learned that the 
quickest way to reach the dispatcher was by radio, the second quickest 
was by telegraph (when it was still available from the street fire alarm 
boxes), and the third quickest was by calling 911.  A call taker can 
ignore the unlisted ten digit administrative line with impunity as long 
as there are any of those other appearances active.  A call for an 
obstructed airway is ranked number one.  A seizure in progress with a 
duration of less than several minutes might be a three, a report of 
structure fire in an occupied multiple dwelling during the hours of 
darkness might be a four, and so forth.  A caller who has not spoken to 
the call taker because their call is coming in on the wrong appearance 
is effectively last.

Now on the issue of VOIP having no first exchange we're probably just 
using the terms differently.  With a CATV carrier the first exchange for 
their telephone service offering is their signal control office for that 
portion of the system.  For a DSL line it is the Central Office 
telephone exchange that the land line that carries the DSL comes from.  
For Dial up service it is were the server's modems are located.  In 
other words for each of these land line technologies it is the location 
were the signal is taken from the last mile medium and inserted onto the 
ISPs equipment.  For the wireless user the first exchange is the 
location that receives her/his radio signal.  To keep the discussion 
simple we will ignore Controlled Environment Vaults and similar 
structures.  That first physical structure were the last mile medium is 
collocated with POTS lines is the place were connection to 911 dedicated 
pathways would occur in the POTS world.  No State Public Service 
Commission or equivalent state agency would ever permit the LECs to 
route 911 calls through their network on the same basis as other calls 
to the telephone central office closest to the PSAP in order to save 
money.  The LECs have provisioned dedicated E911-only trunks that go to 
a Tandem which serves the PSAP. The trunks are in all cases reserved for 
E911.   In most states the pathways are redundant so that cutting a 
cable will not cut off 911 service to an exchange.

Your answer of requiring LECs to have dial tone on every single pair 
would impose a huge financial burden on their subscribers and/or stock 
holders.  Why should they be required to do that when the systems that 
they have in place now work very well.  I have Covad DSL with Earthlink 
as my ISP.  If you clip onto my DSL pair with a non data guard butt set 
you will down my DSL service just as you would any other DSL line.  What 
you wouldn't get with any telephone instrument that you attached 
directly to that pair is any form of dial tone.  Their just isn't any 
connection between that pair and the POTS switching equipment.  That 
pair terminates at Covad's modem equipment.  My DSL service is not piggy 
backed onto a POTS line in order to avoid finger pointing between Covad 
and the LEC.  The LEC sells Covad a clean dry pair.  It is Covad's Modem 
equipment that places the carrier onto that pair and there is no 
telephone number associated with it.  Are you saying that every pair in 
every cable should have dial tone on it?  Would you force the LECs to 
put dial tone on meter loops or dedicated alarm signal lines.  What 
about other leased pairs for say intra company teletypewriter or 
computer network service.  The LECs provide access to the POTS switching 
equipment to paying customers who subscribe to there voice telephone 
service.  They are under no obligation to provide it to anyone else.  In 
my thirty three years of fire and rescue work I have taken many calls 
with a location of down stairs from, across the hall from, next door to 
and so forth.  This is because those homes had no voice telephone 
service.  In most cases the homes had wire pairs to the premise they 
just didn't have telephone service.  What they chose not to pay for they 
didn't get.

Lastly what you highly doubt did occur in some instances when VOIP 
operators vilified local PSAP staff for not answering published non 
emergency numbers promptly in an attempt to shift the blame away from 
their systems.  In both Florida and Michigan the State Fire Chiefs 
Association pulled out the public relations knives and proceeded to 
start cutting up the VOIP folks in the press for deceptive advertisement 
and attempting to operate bargain basement phone service at the expense 
of public safety.  The fight was over very quickly  when the VOIP staffs 
who made the initial accusations of misfeasance against PSAP staffs 
quickly realized they were being cut wide and deep by the press and 
withdrew from the fray to change strategies and do damage control.  Some 
of that damage control was raising the patently false accusations that 
the LECs were denying the VOIP providers access to the 911 system when 
in fact the LECs were saying we will sell you anything you are willing 
to pay for.  It's a capitalist system.  You want something you have to 
pay for it.
--
Master Fire Fighter / Rescuer Thomas D. Horne, speaking only for himself 
and not the
Takoma Park Volunteer Fire Department a cooperating agency of the
Montgomery County Fire & Rescue Service, Maryland, USA



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