Setup Internal Calls Between Sites

[madkit]

Dear all,

First of all, sorry for this thread if it has been posted before. I tried to find but couldn't find. I would like to ask some could be basic questions here. Please bear with me.

I am using a Raspberry Pi 5 as the SBC with 10 free users license. In my home network, I managed to setup user and add IP phones and have internal call. Now I would like to setup another IP phone for a user, but user is physically at another place with different network. May I ask how do i setup the IP phone in order to connect to my SBC and continue to have internal call? Do I have to change the Outbound Proxy (SBC) Address to my network's public address? My public address is a dynamic IP address.

 

[Evolute IT]

Better to use the Webclient in that case, or simply use a router phone that can connect to the PBX directly. The SBC is only meant for your internal local network and cannot work for remote devices.

 

[madkit]

Better to use the Webclient in that case, or simply use a router phone that can connect to the PBX directly. The SBC is only meant for your internal local network and cannot work for remote devices.

Thanks for your reply. Because the remote site is not using any PC, but do have an IP phone but not router phone. Hence I thought the IP phone can connect to my SBC which is behind a dynamic IP address. I thought it would be able to sort out the dynamic IP address and let the IP phone point to my SBC noip address.

 

[bitn2]

No, in that case you need another sbc for this phone.

 

[madkit]

No, in that case you need another sbc for this phone.

But another sbc can connect to my sbc and act as internal call?

 

[madkit]

What about my router acts as a vpn server. And remote site router join as vpn client with split tunneling. So the ip phone can be seen as in the same LAN? Does that work?

 

[fxbastler]

But another sbc can connect to my sbc ...?

No. It's a second SBC which connects to the 3CX.

act as internal call?

Even with a second SBC: yes.

Perhaps for clarification:
If a 3CX is not operated within its own LAN - like your 3CX SMB for example - then you need

1. either the capability of a router phone that connects directly to the 3CX
2. an already existing router phone within the local network through which a regular IP phone connects to the 3CX
3. or a 3CX SBC which allows a regular IP phone to connect to a remote 3CX.

You can connect multiple SBCs to one 3CX. They are only used to extend the connection of local IP phones via a secure encrypted tunnel to a remote 3CX. All calls between such IP phones are internal calls.

 

[bitn2]

What about my router acts as a vpn server. And remote site router join as vpn client with split tunneling. So the ip phone can be seen as in the same LAN? Does that work?

This could work as well. If the remote network can reach your sbc.

 

[fxbastler]

What about my router acts as a vpn server. And remote site router join as vpn client with split tunneling. So the ip phone can be seen as in the same LAN? Does that work?

You don't want that, just trust me on this.
Yes, I could do something like that. I wouldn't do it.

 

[AWS2P]

Do you have a way to use an APP on smartphone instead of deskphone? if so, then just use it as nothing to setup , just install 3CX and provision it on mobile and it's done. no extra cost, no hardware to add, no nightmare to setup

 

[madkit]

You don't want that, just trust me on this.
Yes, I could do something like that. I wouldn't do it.

After checking my public IP address, it seems to be behind CGNAT. Hence I think you are right, it's not possible for me to do this in a cost effective way. Give up. Getting another SBC is the only solution.

 

[madkit]

Do you have a way to use an APP on smartphone instead of deskphone? if so, then just use it as nothing to setup , just install 3CX and provision it on mobile and it's done. no extra cost, no hardware to add, no nightmare to setup

Actually yes, but I purposely want to have a deskphone there...haha.

 

[SteveITS]

You can run the SBC software on Windows, or in a VM. Or use a router phone as mentioned above.