Re: [PLUG] VOip

[Paul <gyoza@comcast.net>]

Art Clemons wrote:

> > Anyone using commercial VOip? I was looking at the AT&T site. They claim
> > they need 90Kb Up/down BW/line/call. That really sounds excessive. 
> > What is
> > this super high fidelity phone connections! I would think they could get
> > by with a lot less then that even with overhead. Given a 3K voice 
> > channel
> > you should be able to sample at 12-16K, Add overhead and control.. so we
> > double that... 32K ... what the heck is the rest? I think verizon 
> > breaks a
> > T1 down into 23 voice channels / 1 control, each 48K. That always seemed
> > like a waste of BW to me.
>
>
> Actually you probably do need that much bandwidth for some calls and 
> to help prevent what I call the "echo chamber" effect.  Remember, 
> telephone calls are really two sets of audio signals, one from you and 
> one from the individual you're talking to.  If you limit the audio to 
> let's say 3Khz like phones used to, the audio often doesn't sound right


Now I get it.  (A little sleep helps.)  Vonage let's you set your 
bandwidth usage from 30Kbps ("normal" quality) to 50Kbps ("high" 
quality) to 90Kbps ("highest" quality).  Mine is set to 90Kbps with no 
noticeable network slowdown and rarely some echo.

> There are cheaper services like Lingo, Packet8 and Vonage.  The only 
> downside is that to really use them throughout a house, you need 
> wireless phones with more than one phone able to access the same 
> service.  It's not fun to be let's say on the 2nd floor and the only 
> phone connected is on the first.  One hint though, get 5.8Ghz phones 
> if you do this.  Also Verizon is offering VOIP too over broadband in 
> case you're not sick of them enough to avoid any additional services 
> from Verizon.
Do *NOT* try Lingo.  Trust me.

You are a little off about the cordless phone issue, assuming you are 
running a cable modem or are willing to use the second pair of wires in 
your two-pair phone line. First options: If you loop your phone line 
back at the demark, then every phone in the house would have access to 
the VoIP box.  Second option: Use one pair of wires for DSL and the 
other for VoIP.


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