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William
September 18th 03, 07:16 PM
Hi All,

can i use a pc and voice modem to be a h.323 gateway?
what software can do this?

thx.
William

Monzai
September 19th 03, 01:06 AM
William wrote:
> Hi All,
>
> can i use a pc and voice modem to be a h.323 gateway?
> what software can do this?
>
> thx.
> William


Dear William,
all you need is a connection to the internet. What you use
to connect to the internet makes only a speed difference.
Have a look at http://www.openh323.org/ for software.
Cheers :-)
Monzai

Webmasters, network managers and admins: http://www.monzai.com/
You'll love it!

Pete Harris
September 19th 03, 07:47 AM
William posts:

> can i use a pc and voice modem to be a h.323 gateway?
> what software can do this?
>
> thx.
> William

Monzai responds:

> all you need is a connection to the internet. What you use
> to connect to the internet makes only a speed difference.
> Have a look at http://www.openh323.org/ for software.

I think more than Internet connectivity is required. William is
asking about a device to bridge between H.323 Voice over IP and legacy
telephone circuitry.

And he's correct, a voice modem could theoretically do the job.
However, I think most, if not all, of the single channel PC voice
modems do not allow simultaneous audio in both directions (they're
'half duplex'), since they're made for IVR not telephony and lack a
second sound chip. So you would have to use two boards somehow.

Does this software exist? I haven't heard of it. The closest
solution I know about it the low-end Digium card, about $100, which
runs on Asterix using a contributed H.3323 stack, but this works with
Linux only. This can be pretty fussy to set up--unless you're a
student, probably better to just buy a low-end H.323 gateway for a
little more money.

Pete
bg.com/qphone.html

NOONE
September 19th 03, 04:41 PM
Pete Harris wrote:

> William posts:
>
>> can i use a pc and voice modem to be a h.323 gateway?
>> what software can do this?
>>
>> thx.
>> William
>
> Monzai responds:
>
>> all you need is a connection to the internet. What you use
>> to connect to the internet makes only a speed difference.
>> Have a look at http://www.openh323.org/ for software.
>
> I think more than Internet connectivity is required. William is
> asking about a device to bridge between H.323 Voice over IP and legacy
> telephone circuitry.
>
> And he's correct, a voice modem could theoretically do the job.
> However, I think most, if not all, of the single channel PC voice
> modems do not allow simultaneous audio in both directions (they're
> 'half duplex'), since they're made for IVR not telephony and lack a
> second sound chip. So you would have to use two boards somehow.
>

Most PC voice (win)modems have duplex sound capabilities! These days, a
single soundchip is basically consists of two channels for stereo sound
purposes.

> Does this software exist? I haven't heard of it. The closest
> solution I know about it the low-end Digium card, about $100, which
> runs on Asterix using a contributed H.3323 stack, but this works with
> Linux only. This can be pretty fussy to set up--unless you're a
> student, probably better to just buy a low-end H.323 gateway for a
> little more money.
>
> Pete
> bg.com/qphone.html

--
NOONE

Pete Harris
September 19th 03, 11:57 PM
> Most PC voice (win)modems have duplex sound capabilities! These days, a
> single soundchip is basically consists of two channels for stereo sound
> purposes.

OK, I'm showing my age! Actually, when I was plugging a Digium card
FXO gateway card into our Asterix lab system, it's outward appearance
was nearly identical to the V.90 modem which was already there...

So as the original poster surmised, it's a simple matter of software
....

Pete
bg.com/qphone

NO_SPAMMERS
September 20th 03, 01:03 AM
Pete Harris wrote:

>> Most PC voice (win)modems have duplex sound capabilities! These days, a
>> single soundchip is basically consists of two channels for stereo sound
>> purposes.
>
> OK, I'm showing my age! Actually, when I was plugging a Digium card
> FXO gateway card into our Asterix lab system, it's outward appearance
> was nearly identical to the V.90 modem which was already there...
>
> So as the original poster surmised, it's a simple matter of software
> ...
>
> Pete
> bg.com/qphone

You may be right in this matter where it is possible to use any voice
capable (win)modem to act as an FXO device; however, from the hardware
point of view, one will need a dedicated computer CPU resources to perform
a voice CoDec, i.e. G.723, to compress/decompress the audio data. I am no
expert in this matter; however, this certainly will consume some CPU
resources ...

--
NO_SPAMMERS

Virgilio Lattanzi
September 20th 03, 12:06 PM
"NOONE" > ha scritto nel
messaggio news:PAEab.520350$o%[email protected]
[...]
> Most PC voice (win)modems have duplex sound capabilities! These days, a
> single soundchip is basically consists of two channels for stereo sound
> purposes.

Are you sure the full-duplex capability is between the analog loop
and the digital interface (pci bus or serial port) ?
AFAIK such capability exists only between the analog loop and
analog in/out (where you are supposed to plug a mic+headphones),
so you need a sound card too, connected by wires to the modem
audio in/out.

I would like to be wrong. Do you know a chipset/modem that doesn't
need a sound card ?

Bye,


--
Virgilio Lattanzi HARPAX srl
Tel: +39 0733 818863 via Fontanella, 38
Fax: +39 0733 819133 62012 Civitanova Marche MC
WWW: www.harpax.com ITALY

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