routing VoIP through a regular phone line

Hello. I would like to set up a linux box connected to a phone line so that
I can connect to it over the internet and receive a dial-tone as though i
had picked up the phone where the linux machine is.

In theory, this seems very simple to do. Once authenticated, the linux box
issues a couple of commands to the modem, starts recording from the modem
and sending that data, and also passing the incoming voice data to the phone
line.

I don't want to have to run some huge VoIP software package. Ideally, this
sort of thing can be achieved in a very lightweight fashion.


Comments please.

"C3" <_> wrote in message
news:413d53ba$0$32424$(E-Mail Removed) u

> Hello. I would like to set up a linux box connected to a phone line
> so that I can connect to it over the internet and receive a dial-tone
> as though i had picked up the phone where the linux machine is.
>
> In theory, this seems very simple to do. Once authenticated, the
> linux box issues a couple of commands to the modem, starts recording
> from the modem and sending that data, and also passing the incoming
> voice data to the phone line.

One must first have the "IP" established before one can accomplish the "VO".

--
use hotmail for email replies

"C3" <_> writes:

>I don't want to have to run some huge VoIP software package. Ideally, this
>sort of thing can be achieved in a very lightweight fashion.

By "some huge VoIP software package" do you mean Asterisk? I agree that
it's not tiny but it's so easy to configure to do such things that it's
easy for me to justify using it on any but the smallest systems.

--kyler

Here is a diagram:

Remote host <---- internet --------> Linux box <---------> modem <------->
phone line

Surely this isn't that hard to set up.


"ynotssor" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
>
> One must first have the "IP" established before one can accomplish the
> "VO".

C3 wrote:

> Here is a diagram:
>
> Remote host <---- internet --------> Linux box <---------> modem <------->
> phone line
>
> Surely this isn't that hard to set up.

That depends on what kind of connection the "internet" in your diagram is.
If it's the same phone line as is connected to the modem then I'd say
forget it.

A single 56K phone modem will not have the bandwidth to achieve this
reliably (quite apart from a phone modem not being able to offer this
reliability in the first place).


--
J

All your bits are belong to us - again.

> If it's the same phone line as is connected to the modem then I'd say
> forget it.

Well, that's obvious. It's my fault for not specifying all the details in
the first place. The internet connection is a cable connection with a fast
download speed, and a 128kbps upload speed.

How do I set it up?

"C3" <_> wrote in message news:<413e4bfb$0$22460$(E-Mail Removed). au>...
> Here is a diagram:
>
> Remote host <---- internet --------> Linux box <---------> modem <------->
> phone line
>
> Surely this isn't that hard to set up.
>
>
> "ynotssor" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> >
> > One must first have the "IP" established before one can accomplish the
> > "VO".

Even with the picture it's not real clear to me just what you want.

Connect to Linux box via internet and have that Linux box provide a
dial tone so that the internet conncected host can then place a
"standard" PSTN voice call?

Via VoIP across the internet to Linux box, which then would have to
decode (in real time) the digital signal, construct an analog signal,
and "relay" the voice signal -- after placing the call and
establishing the connection of course. And it must do the same in
reverse to the signal at the far end to transmit the VoIP packets back
to the internet connected host that "originated" the call.

All this at modem speeds that top out at 33kbps upload? That requires
a (voice)modem at the far end to connect to?

If you think that's easy, better do some serious googling for a week
or two ;-)

If you stopped to think (boy, this should be easy) then you figure
everyone would be doing it and that every Linux distro would provide a
"ready-made" setup/config tool.

So, I'm thinking, I don't understand what you have in mind ...

If this is close to what you have in mind, then something like
Asterisk and an interface card capable of interacting properly with
the PSTN voice system will be the easiest way to go.

Or for something "easier" and some $:
http://www.google.com/search?q=inter...UTF-8&oe=UTF-8

If you have something else in mind ...

regards,
prg
email above disabled

"C3" <_> wrote:
>> If it's the same phone line as is connected to the modem then I'd say
>> forget it.
>
>Well, that's obvious. It's my fault for not specifying all the details in
>the first place. The internet connection is a cable connection with a fast
>download speed, and a 128kbps upload speed.
>
>How do I set it up?

It still doesn't make sense. Why not explain what you want to accomplish?

Your diagram indicates a digital connection from end to end, so the
VOIP would appear to be something required not in the diagram, but
at the two distant ends.

--
FloydL. Davidson <http://web.newsguy.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) (E-Mail Removed)

Floyd L. Davidson wrote:

> "C3" <_> wrote:
>>> If it's the same phone line as is connected to the modem then I'd say
>>> forget it.
>>
>>Well, that's obvious. It's my fault for not specifying all the details in
>>the first place. The internet connection is a cable connection with a fast
>>download speed, and a 128kbps upload speed.
>>
>>How do I set it up?
>
> It still doesn't make sense. Why not explain what you want to accomplish?
>
> Your diagram indicates a digital connection from end to end, so the
> VOIP would appear to be something required not in the diagram, but
> at the two distant ends.
>

The easiest solution is to get an VoIP phone that simply has then to be
connected to your ADSL modem or HUB - They used DHCP to get the necessary
IP, routing and gateway details, but after that your computer doesn't have
to be on. I got a GrandStream BudgeTone-100 Open Standards based VoIP
complete phone (look like normal phone) that you just plug into your hub.
Uses UDP ports 5004 & 5060, which I have set up in my firewall. Everything
after that is just a phone call as usual. For more info see:
http://www.swiftdsl.com.au/swiftvoiceip/index.htm

Cheers. Grahame.

> Connect to Linux box via internet and have that Linux box provide a
> dial tone so that the internet conncected host can then place a
> "standard" PSTN voice call?

That's correct.

> Via VoIP across the internet to Linux box, which then would have to
> decode (in real time) the digital signal, construct an analog signal,
> and "relay" the voice signal -- after placing the call and
> establishing the connection of course.

I have a voice modem. There really isn't any decoding going on. The Linux
box is receiving about 8kB/s from a remote host and then putting that data
through the sound card's DAC, and then passing that onto the voice modem.

> And it must do the same in
> reverse to the signal at the far end to transmit the VoIP packets back
> to the internet connected host that "originated" the call.

Yup.

> All this at modem speeds that top out at 33kbps upload? That requires
> a (voice)modem at the far end to connect to?

Ignore the data capabilities of the modem. The modem's only purpose is to
dial a PSTN line and receive (and send) data from (and to) the sound card.

Thanks.


> If this is close to what you have in mind, then something like
> Asterisk and an interface card capable of interacting properly with
> the PSTN voice system will be the easiest way to go.
>
> Or for something "easier" and some $:
> http://www.google.com/search?q=inter...UTF-8&oe=UTF-8