[VoiceOps] 911 address policy for company phones at home

Ian Blenke ian at blenke.com
Fri Jan 18 17:30:54 EST 2013

On Fri, Jan 18, 2013 at 5:13 PM, Nathan Anderson <nathana at fsr.com> wrote:

> This is all predicated on the notion that the only way that most E911 services work is by binding an address to a telephone number in a database on their end.  Are there any E911 providers that you can transmit an address to in the call signalling, in real-time during call set-up?  That would solve the problem entirely.

MSAG validation and ALI publishing is mostly how things are done
today. Route your E911 through a selective router and have them find
the correct PSAP.

Intrado has (or had) GRISIP for passing GIS information as a
proprietary SIP extension header. I'm not sure if this worked outside
of their ECRC, however.

How would such GIS information get relayed to the > 9000 PSAPs all
over the US? Many of them are still rural TDM.

There has been talk about relaying GIS information in NG911, but I
haven't stumbled on the standard whitepaper on that much less an

As someone working in the Video Relay Service industry for the deaf
and hard of hearing, there is work now in the SIP Forum VRS working
group attempting to deal with passing video, text, and audio from our
customer mobile and video phones. There is only beginning debate in
the FCC working group regarding implementation and staffing of NG911
video interpreters.

The sheer number of ancient TDM based PSAPs, funding, and regulation,
is really the core problem there.

- Ian Blenke <ian at blenke.com> http://ian.blenke.com

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