| gabriel rosenkoetter on 13 Jul 2004 14:22:02 -0000 |
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On Mon, Jul 12, 2004 at 11:35:41PM -0400, Paul wrote: > An alternate phone was the suggestion, not necessarily a land line. One > issue is power or service loss. Service loss Just Doesn't Happen, in my six months experience with Vonage. (Or, more to the point, it does when I take the NAT box between the voip router and the outside world down, but I expect that and it reconnects just fine afterwards.) As for power loss... I doubt I'm the only person out there with physical phones that rely on power as much as the voip box does by virtue of owning only cordless phones. In any case, all of the networking stuff gets an 1100 VA-rated UPS to itself in my house, precisely because of this concern, and phones qualify as networking stuff, in my mind. > With VoIP there are many more points of failure. I really don't think there are many more than regular phones, and I think that they are problems it is possible to insure against. > The other issue is the ease of use and reliability of 911. I > want my 5 year old to be able to get help even if all he does is dial > 911. Just dialing 911 and hanging up will still get you a police visit. That's not a problem I'm about to argue against. I live alone and have no dependents, so I'm not personally concerned, but I understand why you are. A local-calling-only landline seems like the best approach for you (which seems to be what you've done). On Tue, Jul 13, 2004 at 08:15:30AM -0400, Art Alexion wrote: > Now, if the Swarthmore guy was using his packet 8 E911 service > in Sweeten (or more realistically, Minnesota) would his 911 call be > routed to Swarthmore? Just to clarify, the friend of mine with Packet8 service lives in Reno, Nevada and was in "Sweden" (your spellcheck's a bit overactive ;^>). In any case, his 911 call would be routed to the 911 operator for whatever location he'd declared to Packet8. I haven't seen Packet8's interface, but if it's anything like Vonage's, this is something you can change on the fly, so if you were going to be in Minnesota for a month, you could change it (just make sure you change it back; a reminder physically attached to the voip router might be a good idea). > TMDA (Cingular) and GSM (Cingular, ATT and > T-Mobile) is almost always recognizable except with the strongest > signals. Nextel, well... In defense of GSM, its poor appearance in the US is largely because the towers are spread pretty thin. With Cingular/AT&T Wireless together now, my service (from the latter, originally) has gotten much better, and seems to be improving incrementally as the joint company continues to build out. (Note that I got an AT&T Wireless phone because it was the only cell service I'd seen function inside my home. Don't bother trying your Sprint phone inside a building near the Swarthmore trainstation; you'll get no reception.) Anyway, GSM service is definitely identifiable (if nothing else because it's doing conversion to digital signal and then *digital* compression rather than analog audio compression), but with networks like those that exist in Europe and Japan, the low-end behavior that we see some of the time in the US just doesn't happen. It'll be more than a few years till US service works that well, though. (I also got the phone I did because I wanted the possibility to unlock it and drop in a new SIM card for use in Europe or Japan and because of the Bluetooth features and the fact that Apple and SonyEricsson are working together to make the phone--where I dump everyone's phone number--behave well with iSync under Mac OS X.) On Tue, Jul 13, 2004 at 03:45:50AM -0400, Paul wrote: > Vonage offers a dedicated fax line free with it's business package, or > $10 per month with a residential plan. It seems that the cost is for > the additional line. I'm wondering if a fax would work on the regular > line. If not, how do they prevent it from working? What do you mean by "regular line"? The voice line under voip is precisely a digitized and encapsulated transmission, so it goes out as IP packets (you might like TCP, but I'm betting its UDP based on how it performs while other data's going over the line). This introduces too much delay and audio distortion for something that functions by modulating and demodulating multiple audio signals (at different pitches) across a copper wire to function. It's the same reason that you can't use a modem or fax machine through a digital phone system, but must have an analog line (or, at least, an analog/digital MUX at both ends of the digital line). > *Important.* It was pointed out to me that cell phones without active > service do not indicate location; one of the problems with VoIP 911 > relaying. Any cell phone that places a call indicates the network and tower through which it's calling. Whether that information is accessible at the endpoint is a separate question. Relatively few cell phones (and only very new ones) include a GSM chip, which works quite well for this, but is a complete privacy nightmare (don't buy one of these if you can avoid it; tracking by calling cell is plenty for 911 calls). On Tue, Jul 13, 2004 at 08:20:41AM -0400, Art Alexion wrote: > Location is indicated, not by some special feature, but simply by what > cell antenna you are using when you make the call. Unlike E911, as it > has been explained, it has nothing to do with your account. I can't see > why it makes any difference, therefore, whether the account is active. > Jon Nelson might be able to give us a definitive answer on this. Jon? I'd hazard a guess that a cell phone without active service doesn't have a subscriber entry anywhere which means that the 911 systems don't have a provider interface from which to get the calling cell. (Remember that the call comes through just like any other phone call; the information about calling cell isn't in some carrier signal, it's based on the CID information--or, actually, probably the ANI information. I've only a peripheral knowledge of how cell routing works.) This stuff is probably abstracted rather completely from even the 911 operators, so I don't know that Jon would ever have had to deal with it, but you're right, he's probably the regular poster most likely to actually know. -- gabriel rosenkoetter gr@eclipsed.net Attachment:
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