In message TELECOM Digest Editor noted in response to snipped-for-privacy@mytrashmail.com :
Given enough time, a highend GPS receiver can typically get a lock almost anywhere that gets sunlight. Since I suspect most VoIP gear is installed and left in place most of it's life, so it would probably work most of the time.
I've never had a problem getting a GPS lock on a $90 bluetooth GPS receiver in a hotel, or even in most offices, so I suspect it's doable.
It might take a few minutes to get a lock, but not being able to make a 911 call for several minutes after an ATA is powered up shouldn't be a big deal.
Who wants another $90-$200 added to their VoIP gear's price simply for the convenience of not having to type your address into a website?
If you're wanting to roll this out, and assuming that your ISP actually knows where you are. Many people VoIP over dialup on a very regular basis (PPPoE), which doesn't give the ISP any clue about where you're actually located, but they can still get you to the right call center which is all the current proposals really attempt to do anyway.
This could be implemented relatively easily with existing infrastructure if everybody cared enough to make it work.
Establish a domain, lets call it example.com since this is an example.
You could perform a DNS lookup of a magic keyword "local.example.com" which participating ISPs would CNAME to the correct city/state/country's location. The default record (in example.com's zone, for non-participating ISPs) would route you to a call center equipped to put you in touch with correct emergency services providers.
Anycast could be used to assist routing for non-participating ISPs.
When you dial 911 (or 112), your ATA would lookup local.example.com and connect the call to the appropriate location.
The DNS records returned could be in the form of "TXT PSTN
+1.4035551234" (meaning that the call needs to be terminated like any other VoIP to PSTN call) or "TXT 1.2.3.4" forms, where protocols are assigned and managed by the central authority controlling this system.The VoIP adapter would also have the ability to perform lookups for city.state.country.manual.example.com records, to provide the information for a specific locality rather then an unknown/generic record. An ATA might not be able to use this, but a PC-driven emergency system could. It would also allow a user to specify the appropriate call center by city name (for travelers who don't want to rely on local ISPs).
Since DNS is hierarchical, the number of segments could vary, it could get as detailed as suburb.city.state.country if needed, the word "rural" could be used instead of a city if applicable, or a ZIP code lookup could be done by looking up
12345.zip.country.manual.example.com"If the VoIP adapter isn't capable of performing the lookup it would get passed up to the VoIP provider (when applicable) and the VoIP provider could route it based on account information if applicable.
The advantage of this system is that it takes very little additional infrastructure, DNS access is basically a given already, plus it allows an ISP to mirror the zone so things still work when the base provider is down (so a DDoS won't take out 911 for the entire VoIP network)
[TELECOM Digest Editor's Note: One question ... you stated above that 'many people use VOIP over dialup frequently', and that confuses me. I _thought_ the idea of VOIP was to be able to avoid (for whatever reason) telco landlines. And frankly, although VOIP works over a dialup line just as it does with broadband, I really did not think that dialup was 'wide enough' of fast enough to do a very good job. I know that even with a bigger pipe (let's say, for example, DSL or cable internet) if you get too much traffic on the line at one time (for example two or three computers all going at once), as they all contend for space in the pipe, times get tough. And this is what I thought was a chronic condition when using something like dialup to feed your VOIP. Assuming that is not correct, then why wouldn't one simply use the telephone (on the dialup line) to call 911 and eliminate all the subsequent steps in the interim you propose?Now assuming dialup is _not_ a feasable way to run VOIP and that you are using broadband as I (most people?) do; you _still_ have some ISP don't you? In my instance, it is Cableone.net, (a national ISP just like aol.net or others.) Can't they be used -- assuming they would cooperate, etc -- to intercept any '911 dialing' on the VOIP line and route it back to local authorities, etc? The local ISP would be in the best position to know where to route the call, etc. PAT]