[Asterisk-Users] 911 Q

[Andrew Kohlsmith]

On Monday 03 October 2005 12:17, Rich Adamson wrote:
> Think you might have jumped to a conclusion that might not be valid.
> "If" the telco can handle a PRI and will accept callerid from you,
> and each unit has a valid telephone number, then the telco can populate
> the callerid database with names. Those are the only two items the
> telco can provide in real time.

I have some information from the 911 service manager for Bell Canada in 
Eastern Ontario.  

Basically the Public Service Automatic Location Indentification database 
(PSALI) only has allocations for BTNs (Billing Telephone Numbers) -- there 
are no ALI entries for DIDs from Bell Canada at this time, and there is no 
plan to do this.   Basically if you set your outgoing ANI to a DID the PSAP 
office will have no address information, and indeed the switch may end up 
overwriting your ANI with the BTN.

Since DIDs do not have an address associated with them  (makes sense, they are 
only "inward"-numbers by design), you can convert DIDs to LDNs (Local 
Directory Number, same thing but has a directory (address) associated with 
it) -- the unfortunate side-effect of that is that LDNs are all billed 
separately so you would receive a separate bill for every LDN on a PRI.

There is a service (of course!) being offered where you can provide 
specifically-formatted records for the PSALI database.  It's not cheap, it's  
a $2000 setup fee and (IIRC) $500/mo for up to 500 record changes, and a 
two-year contract minimum.  (These figures might be off, it's from memory.)  
However if you subscribe to this service you can assign any municipal address 
to any number and it will make its way into the PSALI database, which is what 
all the primary PSAP offices use to get the address information before 
routing the call to the appropriate secondary PSAP office.

At least with Bell Canada, this is the only way to get your user's address 
information into the database used by the primary PSAP offices.  The 
alternative, of course, is to set up your own primary PSAP system and then 
you can use whatever database and organization system you want, and redirect 
calls to the appropriate secondary PSAP office yourself.

-A.