SIP from a mobile phone

[Zoom123]

Hello,

First post here.

In my home office I have ISDN (2 lines) and an ISDN card in my computer which I can use to send/receive faxes (and I could also use make calls with a soft phone). This same computer is also connected to a LAN with a Wireless router.

Recently I bought a Sony Ericsson mobile phone (J10i2 "Elm") with WiFi and SIP capabilities.

My question is: Can I, without buying additional hardware, use my mobile phone at home (with WiFi and SIP) to make and receive calls from my land line? If yes, how? If no, what would I need to do that?

Thank you

 

[leejor]

No, in your case (using ISDN lines) you would have to purchase an ISDN (to SIP) gateway. You could run 3CX on your existing computer but it would have to be left on all the time, or, at least, when you wanted to use the phone. To get calls to and from the public network, you'd need that gateway. WiFi use on a mobile device goes through batteries quickly, so you would probably be wanting to leave the phone in a charger, most of the time, when you weren't talking on it. adding a couple of SIP desk or cordless phones, could make a gateway purchase worthwhile. It would also open up the possibility of using a low cost VoIP provider for long distance, or even adding a Skype trunk.

You could also just sign up with a cheap VoIP provider and register your phone with them.

 

[Zoom123]

Thanks!

No, in your case (using ISDN lines) you would have to purchase an ISDN (to SIP) gateway.

Is this a hardware only solution, or since I have an ISDN card in my computer I could get a software ISDN to SIP gateway? (assuming that the computer is always on). I currently only want to do this as a test , so I want to do it as cheaply as possible. Reliability and efficiency are not important at this point.

Also, can SIP phones act simultaneously as "normal" phones? If yes, do you need to use 2 separate wires?

 

[leejor]

Is this a hardware only solution, or since I have an ISDN card in my computer I could get a software ISDN to SIP gateway?

I would suspect you'd have to get an additional unit, there may be a card for a PC slot but it would have to be compatible with 3CX. See list of supported gateways...http://www.3cx.com/voip-gateways/

Also, can SIP phones act simultaneously as "normal" phones? If yes, do you need to use 2 separate wires?

I can't recall seeing a combination VoIP/analogue phone, not to say that somewhere there isn't one. You could have a two line analogue phone, one line connected to the PSTN (using two wires)and the second line going to an analogue telephone adapter (ATA), that allows a "regular" phone to work on VoIP. All VoIP phones/ATA's connect to your LAN with Ethernet cables, unless they are WiFi, of course.