Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
John Levine [EMAIL PROTECTED] wrote: [...] Given that we're talking about cell phones, it seems completely likely. Cell phones present the dialed number as a block, so there's no ambiguity between 911 and 911X. I don't know whether UK cell carriers map 911 to 112, but there's no technical reason they can't do so. If people expect 911 to work on mobile phones, they will also expect it to work on the PSTN. rant And why should the UK change its numbering system just because a few dumb Yanks who can't be bothered to learn local customs? Does 999 get through to the emergency services in the NANP? Does 112 work on non-GSM phones? How about Australia's 000? /rant I agree that for VoIP using normal phones through adapters, 911 in the UK won't work. ATAs usually collect digits to send as a block as well, either with the user explicitly dialling # after the number, or implicitly after a timeout. At least that's what I see with Cisco ATA-186, 7940 and 7960 and the Sipura 2000 I've tested. -- It can't go any lower? Last time I checked, the minimum value of a traded security is $0.00. - H. Preisman, on Nortel dropping to $20 a share
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On Monday 25 Jul 2005 10:55 am, Peter Corlett wrote: Does 112 work on non-GSM phones? In most of Europe dialing 112 on any phone on a public phone network, mobile or fixed, should get you an emergency operator. I think in some parts of Europe it may still get you the police, instead of a choice of emergency services, but in most cases that is sufficient, and a damn site better than wondering what the local emergency number is, or trying to decipher the explanation on a public phone box. Whether you'll be able to make yourself understood once connected is another issue entirely. My only concern is the UK government persists in teaching the old (local) 999 number, to avoid confusing the terminally stupid who can't cope with the idea of remembering two emergency numbers. As a result UK citizens end up either not knowing what to dial when abroad, or having to remember which country they are in when dialing for help.
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On 25-jul-2005, at 12:54, Brad Knowles wrote: rant And why should the UK change its numbering system just because a few dumb Yanks who can't be bothered to learn local customs? Does 999 get through to the emergency services in the NANP? Does 112 work on non-GSM phones? How about Australia's 000? /rant It would be nice if everyone in the world could agree on a single emergency services number, which would work when dialed from all types of communication devices. This makes no sense at all. Here in the Netherlands we changed from local numbers (which were great, dial 222333 and I'd actually get a The Hague fireman on the line, but finding the phone book first when attending an out of town emergency is of course less than desirable) to a country-wide number (06-11) in the 1990s, and then to the European number 112 (which I'm sure is costing lives as we speak: you first have to hold for a stupid OPERATOR whom you have to TELL what service and where you want to talk to and then AGAIN hold for the actual service). They knew 112 was in the works when they changed to 06-11, BTW. Anyway, my point being: the current numbers have been drilled into our subconscious very effectively. Throwing that away woulde be an amazing waste of time and money. What should happen instead is that everywhere, the most common ones are made to work as additional CNAMEs for the local one. This whole single number hype should end anyway. 10 years ago the Dutch phone company had at least five different numbers: for b2c sales, b2b sales, outages, billing and so on. Now they only have one number but you have to waste time navigating through a voice response maze. That's not what I call progress. Oh yes: /rant
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
At 1:18 PM +0200 2005-07-25, Iljitsch van Beijnum wrote: What should happen instead is that everywhere, the most common ones are made to work as additional CNAMEs for the local one. That doesn't work. As has already been demonstrated, there are numbers elsewhere in the world with 999 as their area code or local prefix, and I'm sure the same is true for 112, 911, and all the various other emergency services numbers. It's simply not possible to take all the various local numbers around the world and make them work globally as CNAMEs for whatever local area you may be in. There's no sense in hoping for something that you know is completely impossible. It's a waste of your time and effort, and mine. What might possibly be achievable is to take a single number that is universally available without conflicts, or where conflicts would be least painful to resolve, and make that work everywhere -- being made the equivalent of a CNAME for whatever the appropriate local area you may be in. This whole single number hype should end anyway. 10 years ago the Dutch phone company had at least five different numbers: for b2c sales, b2b sales, outages, billing and so on. Now they only have one number but you have to waste time navigating through a voice response maze. That's not what I call progress. That's a failure in their IVR design, yes. However, just because you can create badly designed IVR systems does not necessarily mean that all IVR systems should be outlawed. Just because you can create badly designed web pages doesn't mean that all web pages should be outlawed. Likewise with emergency services numbers. They need to be well-designed, yes. But they needn't be outlawed unversally just because some people are incompetent and cannot create one that works properly. However, as I previously alluded to, these are long-term standards issues that would first need to be worked out with the ITU before there could possibly be any operational issues to be resolved. -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On 25-jul-2005, at 13:45, Brad Knowles wrote: What should happen instead is that everywhere, the most common ones are made to work as additional CNAMEs for the local one. That doesn't work. As has already been demonstrated, there are numbers elsewhere in the world with 999 as their area code or local prefix, and I'm sure the same is true for 112, 911, and all the various other emergency services numbers. As someone else already pointed out: systems like ISDN, GSM and VoIP look at the whole number, not at the individual digits as they come in, like POTS. So 911 and 9114567 are different numbers. It's simply not possible to take all the various local numbers around the world and make them work globally as CNAMEs for whatever local area you may be in. That may be a bit much, but I think 112 and 911 would be a good start. But a real solution would be for the terminal to deduce that the user is trying to call an emergency number and then dial the correct number, whatever that may be at the current location at the current time. What might possibly be achievable is to take a single number that is universally available without conflicts, or where conflicts would be least painful to resolve, Do you think there are numbers like this? Here in NL there was a drastic renumbering 10 years ago, about half the country got a new number. That was to allow 00 for int'l, 0800 and 0900 and 1xx. I don't think anyone feels like doing it again. :-) This whole single number hype should end anyway. 10 years ago the Dutch phone company had at least five different numbers: for b2c sales, b2b sales, outages, billing and so on. Now they only have one number but you have to waste time navigating through a voice response maze. That's not what I call progress. That's a failure in their IVR design, yes. Actually their system isn't that bad compared to others. But it still sucks compared to having different numbers that immediately connect you to the right person. However, just because you can create badly designed IVR systems does not necessarily mean that all IVR systems should be outlawed. No, they should be outlawed because even the good ones are incredibly annoying, and the bad ones lead to suicide. Likewise with emergency services numbers. They need to be well- designed, yes. Unfortunately they leave a lot to be desired. Good reason to stay healthy and avoid accidents. But they needn't be outlawed unversally just because some people are incompetent and cannot create one that works properly. Who said anything about stuff being outlawed?
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
Anyway, my point being: the current numbers have been drilled into our subconscious very effectively. Throwing that away woulde be an amazing waste of time and money. Would it? Are humans that difficult to teach? Is all advertising a waste of time? This whole single number hype should end anyway. In Russia it is simple, there are three numbers: 01 - Fire Service 02 - Police 03 - Ambulance/Medical response Easy to remember especially because the number is written in large figures on the side of every emergency response vehicle. You could even retrofit these numbers into other countries because they are two digit numbers. Although Russia has agreed to implement 112 emergency dialling, the old numbers are still active nationwide. --Michael Dillon
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
Simon Waters [EMAIL PROTECTED] wrote: On Monday 25 Jul 2005 10:55 am, Peter Corlett wrote: [...] Does 112 work on non-GSM phones? In most of Europe dialing 112 on any phone on a public phone network, mobile or fixed, should get you an emergency operator. When I wrote non-GSM, I actually meant mobile phones in the USA that don't use GSM technology so don't have the obligation to treat 112 as special. [...] My only concern is the UK government persists in teaching the old (local) 999 number, to avoid confusing the terminally stupid who can't cope with the idea of remembering two emergency numbers. That's because 999 isn't the old number. 112 is provided for EU reasons, but is not *the* number for emergency services. 17099 is also available (possibly only from BT lines), presumably as some sort of artifact of BT's routing, but isn't exactly advertised either. (Go on, how many Brits here knew about 17099 before I mentioned it here?) As a result UK citizens end up either not knowing what to dial when abroad, or having to remember which country they are in when dialing for help. If you don't even know what country you're in, I don't fancy your chances telling emergency services where you are... -- Of course I lie to people. But I lie altruistically - for our mutual good. The lie is the basic building block of good manners. That may seem mildly shocking to a moralist - but then what isn't? - Quentin Crisp
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On Mon, Jul 25, 2005 at 02:01:33PM +0100, [EMAIL PROTECTED] wrote: This whole single number hype should end anyway. In Russia it is simple, there are three numbers: 01 - Fire Service 02 - Police 03 - Ambulance/Medical response Easy to remember especially because the number is written in large figures on the side of every emergency response vehicle. You could even retrofit these numbers into other countries because they are two digit numbers. Personally, I assert that that's bad design for two reasons: 1) they're too *short*: they pre-empt too much dialling pattern space, and they're hard to recognize as what they are, compared for example to 9-1-1 and 1-1-2. 2) it shouldn't, in general, be the place of *someone reporting an emergency* to have to decide what kind of response they want. In the US, for example, medical emergencies are often first-responded by firefighter-paramedics, because there's a firestation closer than the nearest ambulance. There's no way a caller could know what's closer... Cheers, -- jr 'ah... *telecom* :-)' a -- Jay R. Ashworth[EMAIL PROTECTED] Designer Baylink RFC 2100 Ashworth AssociatesThe Things I Think'87 e24 St Petersburg FL USA http://baylink.pitas.com +1 727 647 1274 ...the rough cannot be mean and the love cannot be true, and that's as wise as I can get at 10 o'clock in the morning. -- Bill Shatner, on being an anti-hero.
RE: 911, (is: pointless) (was: You're all over thinking this) (was: Re: Vonage Selects TCS For VoIP E911 Service)
Summary (and hopeful conclusion) of this thread: Depending on which country you live in, you may have to dial a different number for emergency services. It's true! If you read the entire discussion, you'll be amazed at how many emergency numbers NANOG members can name for various countries, including Russia, France, Australia, UK, Germany, and more. Although it's quite sad to imagine how long it would take an American who is burning alive in some country (let's say Sri Lanka) to guess the emergency number there, 699935, please don't feel obligated to share yet another country's emergency phone number. Instead, if you find yourself in a potentially-fatal situation in a foreign land, just go here: http://www.sccfd.org/travel.html (Trust me. It's faster than searching through the NANOG archives for the right one.) Well, that wraps up this month's international NANOG travel safety thread. Next month, we'll be talking about the best way to hail a taxi in various countries (during a network emergency, of course). -Jason -- Jason Sloderbeck Positive Networks jason @ positivenetworks . Net
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On Mon, 25 Jul 2005 14:09:11 -, Peter Corlett said: If you don't even know what country you're in, I don't fancy your chances telling emergency services where you are... I blinked... Did we leave (Luxembourg / Andorra / Liechtenstein ) already? :) (Sorry, I couldn't resist ;) pgpBKalt7RuMx.pgp Description: PGP signature
Re: 911, was You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
world-wide, so that if you're an American in Europe, you can still call 911 and have that work as expected. Given that there are UK telephone numbers starting 911, this seems rather unlikely. Given that we're talking about cell phones, it seems completely likely. Cell phones present the dialed number as a block, so there's no ambiguity between 911 and 911X. I don't know whether UK cell carriers map 911 to 112, but there's no technical reason they can't do so. I agree that for VoIP using normal phones through adapters, 911 in the UK won't work.
Re: You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
Brad Knowles [EMAIL PROTECTED] wrote: [...] I understand that the carriers have gotten together and made sure that the various 911/112/999 emergency services numbers work world-wide, so that if you're an American in Europe, you can still call 911 and have that work as expected. Given that there are UK telephone numbers starting 911, this seems rather unlikely. By way of example, and to bring VoIP back into the discussion, Bristol (0117) 911 numbers all belong to Magrathea who appear to be the main VoIP-to-PSTN wholesaler for the UK. AFAIAA, Magrathea don't offer access to 112/999, but this is no great loss given that mobile phones are cheap, ubiqitous, and work pretty much everywhere in the UK. Even hermits have them :) -- PGP key ID E85DC776 - finger [EMAIL PROTECTED] for full key Please contribute to the beer fund and a tidier house: http://search.ebay.co.uk/_W0QQfgtpZ1QQfrppZ25QQsassZpndc
Re: You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On Thu, 21 Jul 2005 10:20:07 + (UTC) [EMAIL PROTECTED] (Peter Corlett) wrote: Given that there are UK telephone numbers starting 911 When I worked with Oftel on the design of the new UK numbering schemes, one of my strongest recommendations was for certain prefixes, including 911, to be ringfenced from all local numbering schemes - for exactly the reasons that you are now pointing to. Sadly Oftel were never known for their ability to understand reasoned argument within the technical arena ... A current, and related, problem is the introduction of emergency SMS messaging from cellphones ... a very necessary feature for deaf people to use, where they cannot access a text/relay service (eg when they are in a foreign country) Of course, the design of GSM predicates that such messages will go to the message center in their home country, and as things stand would be routed from there to the home country emergency services, regardless of where in the world the user actually is! -- Richard
Re: You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
On 20 Jul 2005, at 21:46, Brad Knowles wrote: In the case of regular cell phones, if you are roaming on a network in a foreign country, or you have rented a local phone, I understand that the carriers have gotten together and made sure that the various 911/112/999 emergency services numbers work world-wide, so that if you're an American in Europe, you can still call 911 and have that work as expected. Cite? (This isn't my experience at all, although obviously it's possible that the very few occasions I've had to test this have just been localised inability to implement the arrangement you describe.) (Emergency services are obtained by dialling 111 in New Zealand, for the record, just to make your list a little more complete. The physical act of dialling 111 in New Zealand on a rotary phone was the same as dialling 999 in England, however, since the dials in each country were numbered in opposite directions; a New Zealand 1 and an English 9 were both sent as nine pulses.) (Not that any of this has much to do with network operations.) Joe
Re: Vonage Selects TCS For VoIP E911 Service
I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. While I agree that GPS is the likely answer, I wasn't expecting the ability to work inside computer rooms and basements. It doesn't need to work in basements, etc. It only needs to keep a record of the last location it was at when the signal faded away. The emergency service vehicles probably can't get any closer than that anyway. --Michael Dillon
Re: Vonage Selects TCS For VoIP E911 Service
[EMAIL PROTECTED] wrote: I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. While I agree that GPS is the likely answer, I wasn't expecting the ability to work inside computer rooms and basements. It doesn't need to work in basements, etc. It only needs to keep a record of the last location it was at when the signal faded away. The emergency service vehicles probably can't get any closer than that anyway. I wonder how that works with VoIP ATA adapters. Last time I looked they didn't work while I was carrying it around in its box from the dealer home. To sum it up: Using GPS to geo-locate VoIP phones or adapters is broken by design. -- Andre
Re: Vonage Selects TCS For VoIP E911 Service
At 10:32 AM +0100 2005-07-20, [EMAIL PROTECTED] wrote: While I agree that GPS is the likely answer, I wasn't expecting the ability to work inside computer rooms and basements. It doesn't need to work in basements, etc. It only needs to keep a record of the last location it was at when the signal faded away. The emergency service vehicles probably can't get any closer than that anyway. I've been doing some reading on this subject. It seems that both GPS and tower triangulation methods suck. For GPS, the problems are signal acquisition and penetration in urban environments, especially with non-dedicated handheld devices. For tower triangulation, the problem appears to be areas with poor signal coverage where you might only be able to barely see one tower, and where TDoA, AoA, and EOTD aren't going to do you any good. In either case, simply keeping the last known signal lock may very well be one of the worst things you could do. It seems to me that we need to use both technologies in order to get any real hope of reasonably sustainable accuracy, either for E911 or any other location-aware technology. And I'm not convinced even that's enough. So, anyone want to place any bets on what's really going to happen? -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: Vonage Selects TCS For VoIP E911 Service
On Wed, 20 Jul 2005, Andre Oppermann wrote: To sum it up: Using GPS to geo-locate VoIP phones or adapters is broken by design. No, it isn't. Relying on satellite connectivity to do so broken, but that's not how it works anymore. Did you even read the article regarding indoor GPS that I posted earlier in the thread? -- Mikael Abrahamssonemail: [EMAIL PROTECTED]
Re: Vonage Selects TCS For VoIP E911 Service
In either case, simply keeping the last known signal lock may very well be one of the worst things you could do. Depends on what you want to do with the location info. If you want to immediately dispatch a vehicle, then you have to realize that you may be sending one to the edge of the cell tower's range when the caller is many miles away. Or that you might be sending one to the east side of the downtown highrise district when the caller has moved on to the west side of the downtown highrise district. On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. In any case, no solution to E911 and VoIP is likely to meet 100% of its requirements, but if you can improve the situation significantly, then it is still worth doing. --Michael Dillon
Re: Vonage Selects TCS For VoIP E911 Service
Mikael Abrahamsson wrote: On Wed, 20 Jul 2005, Andre Oppermann wrote: To sum it up: Using GPS to geo-locate VoIP phones or adapters is broken by design. No, it isn't. Relying on satellite connectivity to do so broken, but that's not how it works anymore. Did you even read the article regarding indoor GPS that I posted earlier in the thread? I did but those ground based transmitters are only for improving accuracy by sending you the position delta determined vs. real for that region. It doesn't help if you don't receive a GPS signal. That ain't satellite radio which is being terristrically re-broadcast. For more information have a look the descriptions of these augumented GPS systems: http://en.wikipedia.org/wiki/GPS#Techniques_to_improve_GPS_accuracy http://en.wikipedia.org/wiki/Trilateration To sum it up: Without having good GPS reception you can't do trilateration and without it you can't apply any accuracy improvements. -- Andre
Re: Vonage Selects TCS For VoIP E911 Service
[EMAIL PROTECTED] wrote: In either case, simply keeping the last known signal lock may very well be one of the worst things you could do. Depends on what you want to do with the location info. If you want to immediately dispatch a vehicle, then you have to realize that you may be sending one to the edge of the cell tower's range when the caller is many miles away. Or that you might be sending one to the east side of the downtown highrise district when the caller has moved on to the west side of the downtown highrise district. On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. In any case, no solution to E911 and VoIP is likely to meet 100% of its requirements, but if you can improve the situation significantly, then it is still worth doing. I have never seen any real study by the emergency response services on how many problems they actually have other than isolated worst- cases and a lot of political rah-rah. In the end I expect that any technically feasible improvement to the cell phone position accuracy is miniscule to the actual effort and expenditures it requires. So my guess is that the real drivers are the law enforcement agencies wanting to get better tracking abilities. Whether they get out of deal what they are hoping for remains to be seen. Not that they will tell us anyway. -- Andre
Re: Vonage Selects TCS For VoIP E911 Service
At 11:21 AM +0100 2005-07-20, [EMAIL PROTECTED] wrote: On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. If all you use the last known position information for is routing to the correct E911 system, that might be okay. However, one thing I believe you need to also transmit along with the position information is time since last fix, so that you can get some sort of idea how long it's been since that position information was reasonably accurate. If the time since last fix is several hours, then the person might now be on a plane using a picocell or broadband wireless network connection that is not position-enhanced, and using the position information for routing to the presumed correct E911 system may be inappropriate. So long as we give additional information which gives the system an idea of the expected level of age and error in the information, I think the risks should be able to be reasonably minimized. In any case, no solution to E911 and VoIP is likely to meet 100% of its requirements, but if you can improve the situation significantly, then it is still worth doing. I guess it also depends on what you mean by significantly. Is a 10% solution significant? Do you need 90% before you're significant? And what's the cost of false positives, as well as false negatives? I think all these factors need to be considered, when looking at potential solutions. -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: Vonage Selects TCS For VoIP E911 Service
At 12:34 PM +0200 2005-07-20, Andre Oppermann wrote: So my guess is that the real drivers are the law enforcement agencies wanting to get better tracking abilities. Whether they get out of deal what they are hoping for remains to be seen. Not that they will tell us anyway. Actually, the FBI has been at least somewhat open with their disappointment of carrier support for position-enhanced information and compliance with CALEA. I've seen recent articles in the press that has made this obvious. It seems that the problem is that too many people are holding onto their old phones, and the networks which selected GPS as their solution aren't getting enough uptake fast enough on the new position-enhanced models. Contrary to my previous post, Nextel appears to be one of the carriers that selected GPS, and Verizon and Sprint appear to have done the same. ATT, Cingular, and T-Mobile appear to have gone the tower triangulation route. But as far as E911 is concerned, the problem appears that many of the emergency services providers still aren't equipped with the necessary equipment -- the article at http://tinyurl.com/dmzdq is a little old, but the situation was so bad at the time that I can't imagine the entire world has been turned around since. The whole CALEA/E911 issue was known a long time back. Even _Wired_ picked up on it in early 1998, in the article at http://wired-vig.wired.com/news/technology/0,1282,9502,00.html, or http://www.danbrown.com/secrets/digital_fortress/cell_phones.html. And the interaction between VOIP, E911, and CALEA is still getting some traction (see http://www.vonmag.com/issue/2005/jul/features/you_will_conform.htm). -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: Vonage Selects TCS For VoIP E911 Service
It doesn't need to work in basements, etc. It only needs to keep a record of the last location it was at when the signal faded away. The emergency service vehicles probably can't get any closer than that anyway. In the US, that might be true, but, I'm betting that could be very wrong in places like London. I'm betting the station where you boarded the Tube could be a LONG way from where you make the 911 call. Owen -- If this message was not signed with gpg key 0FE2AA3D, it's probably a forgery. pgpCQ8PMo5DiP.pgp Description: PGP signature
Re: Vonage Selects TCS For VoIP E911 Service
In the US, that might be true, but, I'm betting that could be very wrong in places like London. I'm betting the station where you boarded the Tube could be a LONG way from where you make the 911 call. There are very few places in the underground tube system where you can make calls on your mobile. Outside central London where the tube runs aboveground I would expect that GPS reception would be available wherever mobile reception is available, after all the tube trains have lots of windows. But you do point out that it would be shortsighted of mobile operators to not use the location information that is already available in the cell base stations. As for VoIP, well if that is not running over GPRS or 3G then I suppose it's running over Wi-Fi and that the user has to authenticate in order for the Wi-Fi access point to accept his MAC address. Maybe we should lobby government to require Wi-Fi access point manufacturers to include location information in their devices. After that, the VoIP operators and the Wi-Fi access operators should be able to sort out some protocol for sharing the location info. Welcome to the 21st century! They never said it was going to be easy. --Michael Dillon
Re: Vonage Selects TCS For VoIP E911 Service
I guess it also depends on what you mean by significantly. Is a 10% solution significant? Nope. 15% or better. This comes from an old rule of thumb about sales, pricing, etc. If the new supplier doesn't offer 15% or better pricing then the hassles of switching aren't worth it. Or, you can increment the price and keep the business as long as you don't go higher that 15%. Of course in big business, you are more likely to study the actual costs and implications to find an optimal solution. Somehow I suspect that the current FCC regulatory environment is not one in which such detailed studies will be done before deciding. So it's back to rules of thumb and letting the market hash out the details by making mistakes. --Michael Dillon
Re: Vonage Selects TCS For VoIP E911 Service
[EMAIL PROTECTED] wrote: In the US, that might be true, but, I'm betting that could be very wrong in places like London. I'm betting the station where you boarded the Tube could be a LONG way from where you make the 911 call. There are very few places in the underground tube system where you can make calls on your mobile. Outside central London where the tube runs aboveground I would expect that GPS reception would be available wherever mobile reception is available, after all the tube trains have lots of windows. This is unlikely. GPS reception is usually determined by sight of horizon. For example the navigation system in my car has trouble from time to time spotting enough GPS satellites when I'm driving in the inner city of Zurich. It keeps itself updated by compass and tracking the movements/velocity of the car. If a car mounted GPS has trouble keeping up with GPS in a city I highly doubt that a small mobile phone without any line of sight at all would be able to get any meaningful GPS signal reception. The low number of active GPS satellites and their concentration over the middle east don't help getting accuracy and reception higher up in US and EU. The new EU system called Galileo has a larger number of satellites planned which makes chances higher to have a number of the in sight all the time. On top of that it is 20 years further in technology refinement than GPS. OTO it ain't there yet and any speculation on how good it will be is moot until we can see ourselfs. -- Andre
Re: Vonage Selects TCS For VoIP E911 Service
On Wed, 20 Jul 2005, Andre Oppermann wrote: This is unlikely. GPS reception is usually determined by sight of horizon. For example the navigation system in my car has trouble Looking at: http://people.howstuffworks.com/location-tracking4.htm Phase II - The final phase requires carriers to place GPS receivers in phones in order to deliver more specific latitude and longitude location information. Location information must be accurate within 164 to 984 feet (50-300 meters). It does look like the requirements in E911 are designed around what can be done via cellphone based location services without GPS (ie some kind of distance to towers/angle approach). -- Mikael Abrahamssonemail: [EMAIL PROTECTED]
RE: Vonage Selects TCS For VoIP E911 Service
I think this can work. Put a battery backup in the ATA, to power the GPS and real time clock. The ATA will maintain the internet-routable address it's using (not necessarily it's own IP address) indefinitely. If the ATA determines it's routable address (or /23 or whatever subnet) has changed since being disconnected, it prompts (via voice menu on connected phones) that it needs to be taken outside and re-GPS'ed. Flashing light on the box confirms when GPS has synced it's location. Take it back inside, plug it in, and all is ok again. Or something along those lines Chuck Church Lead Design Engineer CCIE #8776, MCNE, MCSE Netco Government Services - Design Implementation Team 1210 N. Parker Rd. Greenville, SC 29609 Home office: 864-335-9473 Cell: 703-819-3495 [EMAIL PROTECTED] PGP key: http://pgp.mit.edu:11371/pks/lookup?op=getsearch=0x4371A48D -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Wednesday, July 20, 2005 5:32 AM To: nanog@merit.edu Subject: Re: Vonage Selects TCS For VoIP E911 Service I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. While I agree that GPS is the likely answer, I wasn't expecting the ability to work inside computer rooms and basements. It doesn't need to work in basements, etc. It only needs to keep a record of the last location it was at when the signal faded away. The emergency service vehicles probably can't get any closer than that anyway. --Michael Dillon
RE: Vonage Selects TCS For VoIP E911 Service
On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. And if by chance you end up in the wrong county, as it happens from mobile phones on occasions, they will immediately transfer you to the right center. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential, proprietary, and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from all computers. 163
RE: Vonage Selects TCS For VoIP E911 Service
I think this can work. Put a battery backup in the ATA, to power the GPS and real time clock. The ATA will maintain the internet-routable address it's using (not necessarily it's own IP address) indefinitely. If the ATA determines it's routable address (or /23 or whatever subnet) has changed since being disconnected, it prompts (via voice menu on connected phones) that it needs to be taken outside and re-GPS'ed. Flashing light on the box confirms when GPS has synced it's location. Take it back inside, plug it in, and all is ok again. Or something along those lines So will you block all useage until you do so? Any voluntary compliance solution will fail the CALEA aspect. And I recall reading somewhere in the trade press that the reason some cellular carriers went to GPS-based solutions was they could not meet the FBI specs for accuracy with tower-timing solutions. And needless to say, I can think of many places both cellular and VOIP cam be used where GPS will be worthless. One other point: both the FBI and EMS want to know which office on which floor of the Empire State Building you are in when you call, not just a 2-D circle of X radius. -- A host is a host from coast to [EMAIL PROTECTED] no one will talk to a host that's close[v].(301) 56-LINUX Unless the host (that isn't close).pob 1433 is busy, hung or dead20915-1433
Re: Vonage Selects TCS For VoIP E911 Service
Andre Oppermann wrote: I have never seen any real study by the emergency response services on how many problems they actually have other than isolated worst- cases and a lot of political rah-rah. In the end I expect that any technically feasible improvement to the cell phone position accuracy is miniscule to the actual effort and expenditures it requires. (putting on my firefighting helmet for a moment) I don't have any studies, per se, but we get enough the house next to X Any Street calls as it is that the technically feasible improvement is an improvement. In San Antonio, people give directions by intersections, and leave it up to the recipient to actually figure out where the destination is. 281 and Bitters represents a ~10 square mile area to most locals, and similar scenarios pop up all over. I-10 runs east and west from El Paso to Houston through downtown. I-35 runs north and south from Dallas to Laredo. Loop 410 is a 54-mile loop around the city. Loop 1604 is a 110-mile loop around the city. Getting cell phone calls from a tourist (of which we have plenty) reporting a wreck at I-10410 narrows it down, but still leaves ~27 miles of inaccuracy. Add in 4-8 exit ramps, 10 square miles of surrounding area, and a language barrier, and you end up with some combination of delayed response, parallel response to each possibility, and increased risk to rescuers and innocent citizens. So yeah, I'd like better locations whenever possible. pt
Re: Vonage Selects TCS For VoIP E911 Service
--- Brad Knowles [EMAIL PROTECTED] wrote: If the time since last fix is several hours, then the person might now be on a plane using a picocell or broadband wireless network connection that is not position-enhanced, and using the position information for routing to the presumed correct E911 system may be inappropriate. If a person is calling 911 from a plane in flight, are we really so concerned about which PSAP receieves the call?The last known fix would likely have been the point of origin in any case... David Barak Need Geek Rock? Try The Franchise: http://www.listentothefranchise.com Start your day with Yahoo! - make it your home page http://www.yahoo.com/r/hs
Re: Vonage Selects TCS For VoIP E911 Service
Re: Vonage Selects TCS For VoIP E911 Service
If a person is calling 911 from a plane in flight, are we really so concerned about which PSAP receieves the call?The last known fix would likely have been the point of origin in any case... If a picocell on board an airplane receives an E911 call, it shouldn't route it to any PSAP. The first responders in this situation are the flight attendants so it should ring the flight attendant's phone. By the way, if GPS works in the air for small aircraft pilots, then why wouldn't it work for cellphones? The last known fix should be 100% up to date and 100% useless. --Michael Dillon
Re: Vonage Selects TCS For VoIP E911 Service
GPS does not work through the fuselage of a aluminum airplane. I've tried. More than once. On Wed, 20 Jul 2005 [EMAIL PROTECTED] wrote: If a person is calling 911 from a plane in flight, are we really so concerned about which PSAP receieves the call?The last known fix would likely have been the point of origin in any case... If a picocell on board an airplane receives an E911 call, it shouldn't route it to any PSAP. The first responders in this situation are the flight attendants so it should ring the flight attendant's phone. By the way, if GPS works in the air for small aircraft pilots, then why wouldn't it work for cellphones? The last known fix should be 100% up to date and 100% useless. --Michael Dillon -- Alex Rubenstein, AR97, K2AHR, [EMAIL PROTECTED], latency, Al Reuben Net Access Corporation, 800-NET-ME-36, http://www.nac.net
Re: Vonage Selects TCS For VoIP E911 Service
Thus spake Kuhtz, Christian [EMAIL PROTECTED] On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. And if by chance you end up in the wrong county, as it happens from mobile phones on occasions, they will immediately transfer you to the right center. At least around here, the PSAP folks answer with cityname 911 and you can request a transfer to a nearby PSAP on the rare occasion they get it wrong. Other areas in the country, however, don't have the ability to transfer; IIRC the SF Bay Area is a prime example of each PSAP not being linked to its neighbors (unless they've improved recently). One enhancement I think is needed is a way to convey the level of confidence in the location information so the PSAP folks know if they need to verify it with the caller. Time since last updated is probably a good input to that, but so are the historical frequency of change, the precision of the last fix, the method (GPS vs tower vs manual entry), and probably others. Another complication is what to do with people whose location changes (either due to movement or varying fixes) during the 911 call. S Stephen Sprunk Those people who think they know everything CCIE #3723 are a great annoyance to those of us who do. K5SSS --Isaac Asimov
Re: Vonage Selects TCS For VoIP E911 Service
On Wed, 20 Jul 2005, Alex Rubenstein wrote: GPS does not work through the fuselage of a aluminum airplane. I've tried. More than once. The gps carrier frequency is 1575.42mhz a decent gps antenna is unfortunately a bit larger than most small gps recivers let alone cellphones. multipath cancelation is a serious issue when dealing with gps, and being in a aluminum tube mailer, under tree cover or inside commercial construction doesn't help your situation when all you have is a tiny patch antenna printed on a pcb. On Wed, 20 Jul 2005 [EMAIL PROTECTED] wrote: If a person is calling 911 from a plane in flight, are we really so concerned about which PSAP receieves the call?The last known fix would likely have been the point of origin in any case... If a picocell on board an airplane receives an E911 call, it shouldn't route it to any PSAP. The first responders in this situation are the flight attendants so it should ring the flight attendant's phone. By the way, if GPS works in the air for small aircraft pilots, then why wouldn't it work for cellphones? The last known fix should be 100% up to date and 100% useless. --Michael Dillon -- -- Joel Jaeggli Unix Consulting [EMAIL PROTECTED] GPG Key Fingerprint: 5C6E 0104 BAF0 40B0 5BD3 C38B F000 35AB B67F 56B2
Re: Vonage Selects TCS For VoIP E911 Service
Perhaps the tube wasn't the best example, although, I remember making cell calls from places in stations I'm pretty sure I wouldn't have gotten GPS coverage. In any case, the fundamental assumption that detailed location information for e911 on every phone or phone-like capability is desirable is, in my opinion, flawed. I understand why the police-state zealots at places like the FBI want it, but, I'm not sure why network operators are so anxious to solve this problem. Personally, I'm perfectly happy that my laptop and it's SIP soft-phone aren't location traceable at all times. Owen pgpw8V3c1nUmv.pgp Description: PGP signature
RE: Vonage Selects TCS For VoIP E911 Service
Why not standardize this across the board for all access devices? As an example if my Broadband provider was required to enter location information in my cable modem so that when I connected a VOIP device (ATA, IAD, PC, etc) it would query the first IP device it encountered and gather location data that would solve a lot of these problems. Any solution can be circumvented so no solution will be perfect, but this idea seems easy enough to accomplish with existing technology. It would even fix the VPN connection issue, unless the user was purposefully trying to obfuscate himself in which case I don't think we are necessarily concerned about his ability to contact emergency services. Shane -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Wednesday, July 20, 2005 7:22 AM To: nanog@merit.edu Subject: Re: Vonage Selects TCS For VoIP E911 Service snip Maybe we should lobby government to require Wi-Fi access point manufacturers to include location information in their devices. After that, the VoIP operators and the Wi-Fi access operators should be able to sort out some protocol for sharing the location info. Welcome to the 21st century! They never said it was going to be easy. --Michael Dillon
RE: Vonage Selects TCS For VoIP E911 Service
Forget defeat, just look at the normal margin of error... Forget fixed-line services, location is easy to solve for that. Let's look at things like a guy sitting on a mountain top with a BBQ grill antenna, and amp, and a WiFi card. I could make VOIP calls from Apple's public Wireless network from 25 miles away on top of Loma Prietta if I wanted to. (In fact, I did once, just to test it). If someone put a wireless bridge up there, then, I could make the same call from downtown Monterey. The first IP device would still be in Cupertino. I'd be in a different county (at least 2 counties away), in a different LATA, and, in completely different CHP dispatch zones. Even CDF would expect me to be talking to a different dispatch center. Doing this right is not only hard, but, it's also just not that desirable in my opinion. It's a huge invasion of privacy as far as I'm concerned. Owen --On July 20, 2005 3:19:41 PM -0500 Shane Owens [EMAIL PROTECTED] wrote: Why not standardize this across the board for all access devices? As an example if my Broadband provider was required to enter location information in my cable modem so that when I connected a VOIP device (ATA, IAD, PC, etc) it would query the first IP device it encountered and gather location data that would solve a lot of these problems. Any solution can be circumvented so no solution will be perfect, but this idea seems easy enough to accomplish with existing technology. It would even fix the VPN connection issue, unless the user was purposefully trying to obfuscate himself in which case I don't think we are necessarily concerned about his ability to contact emergency services. Shane -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Wednesday, July 20, 2005 7:22 AM To: nanog@merit.edu Subject: Re: Vonage Selects TCS For VoIP E911 Service snip Maybe we should lobby government to require Wi-Fi access point manufacturers to include location information in their devices. After that, the VoIP operators and the Wi-Fi access operators should be able to sort out some protocol for sharing the location info. Welcome to the 21st century! They never said it was going to be easy. --Michael Dillon -- If it wasn't crypto-signed, it probably didn't come from me. pgpAFj7DpsUGA.pgp Description: PGP signature
You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
I don't know all that much about commercial VOIP service or GPS, but it seems to me I've just read lots and lots of messages citing weird cases where locating a VOIP phone won't work well as evidence that the whole idea is a failure, while none of those cases appear to have much to do with the problem that people have been trying to solve. The end result of this is that a bunch of people who have loudly written the problem off as impossible then start loudly complaining that those working on the problem didn't ask them how to do it. The basic problem, if I understand correctly, is this: For the last several years, anybody picking up phone installed in a reasonably standard way and calling 911 could expect that if weren't able to explain where they were, the police would show up anyway. It was hard to see this as espionage or as a civil liberties violation -- the wire goes where the wire goes. Now we've got competition among providers of wire line residential phone service, and the competitors are mostly VOIP companies who provide their service over the users' cable modems. Since this service is being marketed as equivalent to regular home phone service, and used that way by lots of its customers, it seems reasonable to expect that calling 911 from it would work the same way. There's a minor problem -- the VOIP carrier often doesn't provide the wire, and thus doesn't know where the wire goes -- but that seems easy enough to get around. The simplest way to do it would be to ask two questions when the service gets installed: Is it going to be used in a fixed location, and if so, where? Asking the same questions again whenever the billing address changes should keep this reasonably up to date. There are, of course, other ways to do this, which might also work. Whether GPS in the ATA box will work has already been discussed to death here. Requiring the cable or DSL providers to map IP addresses to installed locations would presumably also work, although with many more layers of complexity to go through to have useful information accompany a phone call. Anyhow, I'm sure if we leave those questions to those who have to implement it, they'll figure out something that doesn't require too much completely extraneous work on their parts. There are, of course, VOIP installations where this won't work. I use a VOIP soft phone through a gateway in San Francisco to call the US from countries where using my US cell phone is expensive, and there are plenty of other people who use VOIP phones in much the same way. Owen maybe isn't quite unique in his bizarre scenario of trying to hide his location by using his wi-fi phone via repeaters from two counties away from the base station. But these scenarios aren't at all relevant to the problem at hand. If I need urgent help in a hotel room in a foreign country, I'll grab the hotel phone and call somebody local rather than trying to patch a call through to the US via my computer. And if Owen were to die because he deliberately hid his location when calling 911 and the ambulance couldn't find him, it would be hard to argue that it would be anybody's fault but Owen's. At some point it makes sense to solve the problems you can solve, rather than inventing new ones. Yes, this ignores the cell phone issue, which seems rather different because they're almost always portable. It's already had years of work put into it, and doesn't need to be reinvented here. -Steve
Re: You're all over thinking this (was: Re: Vonage Selects TCS For VoIP E911 Service)
At 4:19 PM -0700 2005-07-20, Steve Gibbard wrote: At some point it makes sense to solve the problems you can solve, rather than inventing new ones. True enough. However, the tough problems are always the ones you never thought of before you started building the system. Therefore, it helps to try to come up with as many scenarios as you can, and try to find the various weaknesses in the system. You might decide to not try to do anything to fix them, but you should at least be aware of them. For example, one example came to me tonight -- get a CDMA mobile phone with EV-DO and a flat-rate subscription, then run a SIP/VOIP softphone over that. Yes, the cost of the EV-DO flat rate is high, but a few short duration long distance calls per month could very easily exceed the monthly rate you'd pay. And in times of trouble, people frequently grab the device they're most familiar with, and not necessarily the right one for the job at hand. In the case of regular cell phones, if you are roaming on a network in a foreign country, or you have rented a local phone, I understand that the carriers have gotten together and made sure that the various 911/112/999 emergency services numbers work world-wide, so that if you're an American in Europe, you can still call 911 and have that work as expected. But in the case of the EV-DO softphone, things get nastier. And I can see companies deciding to go with a dedicated EV-DO softphone, to save on overall expenses. -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: Vonage Selects TCS For VoIP E911 Service
[EMAIL PROTECTED] wrote: On the other hand, maybe all you want to do is to route the call to the right E911 center. In that case, as long as you are in the right county you are probably OK. This is actually more important then it sounds. Not long ago I was driving around in Northern New Hampshire on I93 and saw a situation I believed should be reported to the police. I used my cell phone to dial *SP (which I saw on many signs in Massachusetts claiming it was how you called the State Police). Well, someone answers State Police and I begin to describe where I am. Much confusion results until I realize that I am talking to the MASSACHUSETTS State Police even when in Northern New Hampshire! -Jeff --- = Jeffrey I. Schiller MIT Network Manager Information Services and Technology Massachusetts Institute of Technology 77 Massachusetts Avenue Room W92-190 Cambridge, MA 02139-4307 617.253.0161 - Voice [EMAIL PROTECTED]
Re: Vonage Selects TCS For VoIP E911 Service
On Mon, 18 Jul 2005, Daniel Senie wrote: use the customer's billing address, attempt to determine location based on IP address or some other voodoo? It'll be interesting to see if they If you look at the webpage of telecomsystems (http://www.telecomsys.com) they state that their platform is GPS based. I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. Article regarding indoor GPS and other locator service. http://www.gpsworld.com/gpsworld/article/articleDetail.jsp?id=3053 If you can put a locator into a cellphone, I see no reason why you cannot do the same in a VoIP unit. -- Mikael Abrahamssonemail: [EMAIL PROTECTED]
Re: Vonage Selects TCS For VoIP E911 Service
Well... It will be most amusing if the 911 dispatchers start a deluge of calls and letters asking the FCC What the hell were you idiots thinking? when they realize what the FCC has done here. It's a bad rule on the FCC's part showing they don't understand the technology and think that VOIP is just TPC/IP (The Phone Company over Internet Protocol). I hope it doesn't kill anyone, but, other than that likely outcome, I gotta say it will serve them right. Owen --On Monday, July 18, 2005 23:07 -0400 Daniel Senie [EMAIL PROTECTED] wrote: At 09:06 PM 7/18/2005, Fergie (Paul Ferguson) wrote: http://www.advancedippipeline.com/166400372 Interesting. No ability to opt-out, and no signup option. So will they use the customer's billing address, attempt to determine location based on IP address or some other voodoo? It'll be interesting to see if they manage to handle vonage boxes that are connected over VPN tunnels that terminate far from where the IP addresses appear to be. Also, Vonage promotes the take your phone service with you idea, so there's a real opportunity for problems. This should be interesting to watch. -- If this message was not signed with gpg key 0FE2AA3D, it's probably a forgery. pgpGZG7h5QacK.pgp Description: PGP signature
Re: Vonage Selects TCS For VoIP E911 Service
If you can put a locator into a cellphone, I see no reason why you cannot do the same in a VoIP unit. Just because you can does not mean it is a good idea. I like being able to have a phone that cannot be accurately located. I won't be buying any VOIP products that can. Owen -- If this message was not signed with gpg key 0FE2AA3D, it's probably a forgery. pgpTPykOhT7FX.pgp Description: PGP signature
Re: Vonage Selects TCS For VoIP E911 Service
Speaking on Deep Background, the Press Secretary whispered: On Tue, 19 Jul 2005, Owen DeLong wrote: Just because you can does not mean it is a good idea. I like being able to have a phone that cannot be accurately located. I won't be buying any VOIP products that can. Then I guess you should talk to FCC and ask them to lighten the demands on the VOIP operators to provide that service. Don't bother. The driving force is really the FBI, not the FCC. And the cell carriers are already in trouble because too many suspected terrorists^H^H^H citizens are not junking their old non-GPS-bugged phones fast enough. http://files.ctia.org/pdf/filings/050630_E911_Waiver_Petition.pdf -- A host is a host from coast to [EMAIL PROTECTED] no one will talk to a host that's close[v].(301) 56-LINUX Unless the host (that isn't close).pob 1433 is busy, hung or dead20915-1433
Re: Vonage Selects TCS For VoIP E911 Service
At 02:48 AM 7/19/2005, Mikael Abrahamsson wrote: On Mon, 18 Jul 2005, Daniel Senie wrote: use the customer's billing address, attempt to determine location based on IP address or some other voodoo? It'll be interesting to see if they If you look at the webpage of telecomsystems (http://www.telecomsys.com) they state that their platform is GPS based. I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. While I agree that GPS is the likely answer, I wasn't expecting the ability to work inside computer rooms and basements. Guess based on the following article that it's possible. So, I guess we'll be seeing Vonage replacing the Cisco ATA-186's with something that does GPS. I suppose a downside is folks using the Vonage boxes outside the US via VPN will be traceable by Vonage and could get shut down, if Vonage wanted to enforce such. Article regarding indoor GPS and other locator service. http://www.gpsworld.com/gpsworld/article/articleDetail.jsp?id=3053 If you can put a locator into a cellphone, I see no reason why you cannot do the same in a VoIP unit. VOIP units don't walk near windows or outdoors, but given the claims made in the article, I guess it'll be possible. Perhaps some nice inexpensive NTP sync hardware will come out of this too. If the chips will work in the environments they list, perhaps they'll also work in data centers, if all the tweaks discussed don't affect clock sync accuracy too much.
Re: Vonage Selects TCS For VoIP E911 Service
On Tue, 19 Jul 2005, Daniel Senie wrote: I suppose a downside is folks using the Vonage boxes outside the US via VPN will be traceable by Vonage and could get shut down, if Vonage wanted to enforce such. I think the ground based radio transmitters needed for indoor operation isn't around much outside the US. I was very surprised when I got a cellphone-based GPS navigator from AVIS last time I was in the US, and it started working inside the terminal building. -- Mikael Abrahamssonemail: [EMAIL PROTECTED]
Re: Vonage Selects TCS For VoIP E911 Service
At 6:45 PM +0200 2005-07-19, Mikael Abrahamsson wrote: I think the ground based radio transmitters needed for indoor operation isn't around much outside the US. I was very surprised when I got a cellphone-based GPS navigator from AVIS last time I was in the US, and it started working inside the terminal building. I had one of those, too. It was a Nextel phone. However, I don't believe those use actual GPS signals. I believe those are actually using triangulation from the cell phone towers (e.g., Time Difference of Arrival, Angle of Arrival, and/or Enhanced Observed Time Difference). They aren't as accurate as GPS, but they will give you reasonably accurate position information anywhere you can get a decent cell phone signal. I have heard about new highly accurate/low-cost single-chip clocks that would help improve accuracy of cell phone tower triangulation, and would hopefully also be something that could be put in standard desktop and laptop computers, making it much easier to run software such as NTP to keep the system clocks much closer to the correct time. -- Brad Knowles, [EMAIL PROTECTED] Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin (1706-1790), reply of the Pennsylvania Assembly to the Governor, November 11, 1755 SAGE member since 1995. See http://www.sage.org/ for more info.
Re: Vonage Selects TCS For VoIP E911 Service
Perhaps -- but how does it work inside? Are we relying/requiring the user to put up a GPS antenna? On Tue, 19 Jul 2005, Mikael Abrahamsson wrote: On Mon, 18 Jul 2005, Daniel Senie wrote: use the customer's billing address, attempt to determine location based on IP address or some other voodoo? It'll be interesting to see if they If you look at the webpage of telecomsystems (http://www.telecomsys.com) they state that their platform is GPS based. I see no other way of doing this reliably than to put some kind of GPS device into the VoIP unit. Article regarding indoor GPS and other locator service. http://www.gpsworld.com/gpsworld/article/articleDetail.jsp?id=3053 If you can put a locator into a cellphone, I see no reason why you cannot do the same in a VoIP unit. -- Alex Rubenstein, AR97, K2AHR, [EMAIL PROTECTED], latency, Al Reuben Net Access Corporation, 800-NET-ME-36, http://www.nac.net
Re: Vonage Selects TCS For VoIP E911 Service
google 'dead reckoning'. The higher end nav systems and gyros, for specifically this reason. On Tue, 19 Jul 2005, Mikael Abrahamsson wrote: On Tue, 19 Jul 2005, Daniel Senie wrote: I suppose a downside is folks using the Vonage boxes outside the US via VPN will be traceable by Vonage and could get shut down, if Vonage wanted to enforce such. I think the ground based radio transmitters needed for indoor operation isn't around much outside the US. I was very surprised when I got a cellphone-based GPS navigator from AVIS last time I was in the US, and it started working inside the terminal building. -- Alex Rubenstein, AR97, K2AHR, [EMAIL PROTECTED], latency, Al Reuben Net Access Corporation, 800-NET-ME-36, http://www.nac.net
Re: Vonage Selects TCS For VoIP E911 Service
At 09:06 PM 7/18/2005, Fergie (Paul Ferguson) wrote: http://www.advancedippipeline.com/166400372 Interesting. No ability to opt-out, and no signup option. So will they use the customer's billing address, attempt to determine location based on IP address or some other voodoo? It'll be interesting to see if they manage to handle vonage boxes that are connected over VPN tunnels that terminate far from where the IP addresses appear to be. Also, Vonage promotes the take your phone service with you idea, so there's a real opportunity for problems. This should be interesting to watch.
