<<   <   Page 2 / 5   >   >>
Yabba 12/5/2012 | 1:25:20 AM
re: VOIP vs PSTN >> I agree with your correcting the original poster with respect to the exchange line types, but my understanding was that public phone lines used 48v *AC* not DC.

Actually, the nominal voltage is -48Vdc, using positive ground.
ironman 12/5/2012 | 1:25:19 AM
re: VOIP vs PSTN I've been using Vonage for almost a year, quality has no noticable difference (at least to these ears or anyone I call).

Echo isn't an issue, but furtherest I call is 2200 miles (4400 round trip).

Occassionally I get issues with dropping, but never in a call; generally when the call is dialed it dropped immediately (very little percentage of the total). Generally I'd say the biggest issue was the cable provider staying up (certainly not 5-9's).

Cann't beat the price and 911 isn't an issue for me. The coolest part is the web based VM (beats voice message recorders).

Ben Crosby 12/5/2012 | 1:25:15 AM
re: VOIP vs PSTN Thanks. I should have researched that before I posted. My multimeter shows 51.5v DC here in Canada. Hmm this raises interesting ideas about trickle charging batteries from the phone line (joking :D)

Assumption is the mother of all mistakes :)
jaynad 12/5/2012 | 1:25:12 AM
re: VOIP vs PSTN 1) Perhaps I was just lucky, but with a decent quality and size (2200VA) UPS at home, powering just my DSL modem and residential gateway, I stayed online throughout the power outage across most of the east of North America. This implies that my provider had adequate backup power for their IP network, as did many other locations. In fact, I'd welcome someone pointing me to a good study of the effects of that outage on the big-I Internet. I hunted on CAIDA, but nothing really interesting.

Wow, that is real nice. I have my home network on a UPS too but whenever the power goes out I lose my network access. I'm in Canada on cable broadband (Rogers). I'm guessing that if I took DSL from the phone company it might stay up during power outages.

The issue with 911 isn't so much that I care about it - it's just that emergency access during power failures is mandated by legislation (it's the law) in many US locations.
jaynad 12/5/2012 | 1:25:12 AM
re: VOIP vs PSTN Well...you can take a few miliamps from the line while it's on-hook. You're not supposed to though ;-)
jaynad 12/5/2012 | 1:25:12 AM
re: VOIP vs PSTN On-hook voltage is -48VDC, off-hook it drops to around 24VDC depending upon how far you are from the CO and how many phones are in use. Ring voltage is ~120VAC @ 20Hz so yes, you can get a bit of a shock (fairly limited current so it's not overly dangerous). There are minor differences from country to country but they're not really significant. You can connect a basic analog phone ANYWHERE and it will work. The established 100 year old analog telecom standards are what make the PSTN tough to displace.

VoIP is absolutely the future. I'm just saying that there will be an extended period of co-existance with the PSTN.

optoslob 12/5/2012 | 1:25:11 AM
re: VOIP vs PSTN Geoff,
I've been using Skype for about 8 months now and find it to be a fantastic service. I travel a lot internationally and I'm sick of exorbitant Hotel phone bills and International roaming charges "when available".

I had a recent experience where I made some very long calls "several hours each" from Houston to Taipei from within a hotel. A friend made similar calls and received a $300US hotel phone bill for a total of 2 days, my costs were ZERO. 10baseT Internet hook-up was free in this hotel.

I've sometimes had massive delays particularly in the Middle East, but generally this is not a problem in Asia or the US. I also don't mind the longish delays because I'm usually using the voice link to discuss business aspects of a PowerPoint presentation or something similar, so the conversation is more intermittent than a normal telephone conversation.

gbennett 12/5/2012 | 1:25:10 AM
re: VOIP vs PSTN Hi optoslob,
Don't get me wrong, I'm a huge fan of Skype too. I agree with you that it could reduce the "travelling worker" costs dramatically.

A couple of months ago a friend of mine called me on Skype from a hotel room in Germany - and not on ADSL, but on dial-up! The quality was fabulous, and no dropped call that time.

I think I may be on to the delay issue. With the UK-France call I mentioned we had a big delay across the IP path, so not much we could do there. But I also found delays on a UK-UK call. As a check I logged off and back onto Skype. It took a while to settle down, but then the call delay was fine. I suspect because I leave Skype on all the time, the Skype "virtual topology" I was using became sub-optimal, with a huge delay.

If you're connecting and disconnecting frequently you won't see this problem.

Packet Man 12/5/2012 | 1:25:07 AM
re: VOIP vs PSTN "I'm a definite VoIP convert, and I'll use the service whenever I can. But it's not appropriate to compare it to circuit voice just yet." - Geoff

Hi Geoff,

I am in Halifax, NS, Canada, and I use Internet VoIP almost daily. I have talked with people in over 20 countries all over the world, and to date each 'session' was better then the PSTN. The audio quality and clairty was better, the ease of dialing was better (can't get much simiplier than a click from an adress book), and it was FREE FREE FREE!!!
Packet Man 12/5/2012 | 1:25:07 AM
re: VOIP vs PSTN Telecom NZ to axe 600 telephone exchanges by 2012

Telecom NZ to axe 600 telephone exchanges by 2012

Incumbent operator plans NZ$120m fibre-optic network rollout.
New Zealand's largest fixed-line telephone company, Telecom Corp., will axe 600 local telephone exchanges by 2012 and will spend NZ$120 million over the next five years rolling out fibre optic cable to its roadside cabinets, the Dominion Post newspaper reported on its Web site Monday.

About 60% of the telephone lines which connect Telecom's roadside cabinets to its local exchanges are copper, with the remainder already upgraded to fibre, the report said.

As part of its planned NZ$1 billion move to a "next generation" internet protocol network, Telecom will do away with its local exchanges and run fibre optic cable from all its roadside cabinets to about 100 existing larger exchanges.

<<   <   Page 2 / 5   >   >>
Sign In