BSNL FTTH voice. Is it possible to use landline and SIP together?

[Joyous]

Is it possible to use landline phone along with SIP software-based calling setup? What I mean is, I do need a landline phone connected to RJ11 port, also need software-based calling set-up in mobile phone using software like Grandstream client..

Is it possible?

 

[abX]

No. SIP authentication will fail on the second connection

 

[pillaicha]

You are allotted only a single SIP line. So if you can terminate that SIP line at, say an IP PBX, which could be running from a simple Raspberry Pi, you can configure the IP PBX, running Asterisk or similar, however you want with multiple lines downstream. You will be able to use only one device at a time to make outgoing calls, but you can certainly configure Asterisk to have multiple ringing for incoming calls, call conferencing, etc.

You can even have your Android phone register VOIP/Sip while you're outside if you can have a static IP setup at your home, or even a DDNS setup, wherein you can maintain your SIP registration with the IP PBX.

So simply put, you are effectively originating and terminating your primary SIP line at the IP PBX and then configuring everything else downstream to work as VOIP, by making use of something like Asterisk to run your IP PBX.

 

[Joyous]

Thanks @abX and @pillaicha

@pillaicha Can you let me know how to use Granstream wave app in my mobile when I am outside of my wifi range? I could use Granstream wave app and make calls and receive when I am inside my wifi range. I have set it up..

How to use my SIP phone client when I am outside my wifi range? I have DDNS already set up.

 

[abX]

No SIP client will work outside your LAN.

You need to setup your own PBX / SIP host, open it to the internet and then connect GS Wave or any other SIP client to your own SIP host.

You can use 3CX PBX. Install it on any raspberry pi in your LAN, and configure a static route on your modem/router to route BSNL SIP traffic through BSNL VoIP WAN.


If you use 3CX , you don't need any third party SIP client as they have a robust SIP client.

 

[pillaicha]

In addition to the above, make sure your Internet provider isn't using CGNAT. It's the most common reason for blocked incoming ports even when you have DDNS correctly set up. If your provider uses CGNAT, then the only option you have is either to purchase a static IP or use a cloud service to route traffic via proxy/VPN.

 

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