View Full Version : Modem port for VoIP

Mar 27, 2013, 04:34 PM
Can the modem port (rj11?) on older macs like ppc be used for connecting a landline phone for voip like skype? Thinking there might be some software that does the conversion that ata voip adapters do.

Mar 27, 2013, 06:42 PM
I would say that that is possible, but not very probable.

Skype (and VOIP in general) need a certain minimum speed to work. Dial up just cannot get there and so your attempt to communicate would probably fail before you even connected.

Mar 28, 2013, 11:44 AM
I meant that the port would be used for connecting a landline phone, since it's the same port. Internet connection is by LAN of course.

Aug 28, 2013, 05:41 AM
Yes , it is possible to connecting a landlines phone from modem for VoIP but if it is not working you can setup your VoIP system to send some keep-alive traffic that will let the modem know it has to hold a port open.

Aug 28, 2013, 06:52 AM
Do Mac modems have the ability to transmit voice? From what I understand not all modems do as they are designed to transmit data rather than voice. Yes I understand that the voice is packetized on the Mac end coming off the internet, but the voice coming off the POTS telephone would need to be packetized by the modem or the software. If not then the idea is a non-starter.

Seems it would make more sense to get an ATA device and put it on your network or attach is to the Mac via ethernet port and sharing and achieve pretty much the same thing. I know Skype sells specific Skype ATA devices and so do other VoIP providers like Vonage. If you sign up with one of the various SIP providers you may be able to use pretty much any SIP telephone on your network without an ATA or an ATA on the network programmed with the correct SIP information and then the old analog telephone in one of the ATA ports.

Aug 28, 2013, 12:42 PM
Some of the PowerPC G3 and G4 era modems can do voice. I don't think any of the AL Powerbook/G5 ones can. I don't think the Mac's modem can do what you want it to. The land line phone won't ring as modems don't have the ability to make a phone ring (without the help of external hardware). The software to take a VoIP call and route the audio to the modem doesn't exist either.