SIP Proxy for 3CX

[amanjuman]

Hi,

In my country government blocked the SIP port and traffic at the IIG level, which means no one can use any foreign SIP trunk, only local SIP works fine.
As a result, I'm not able to use the Twilio SIP trunk on 3CX. When I take a backup of 3CX and host it on an outside country network like
AWS or Digital Ocean it works fine.

Now I wonder if there is any way to set up proxy/VPN so that 3CX will connect Twilio SIP Endpoint through it?
In that case, I would use AWS or any other network to act as a proxy and add it to the Twilio setting, and later connect it on 3CX.
Thanks

 

[Evolute IT]

Hi,

In my country government blocked the SIP port and traffic at the IIG level, which means no one can use any foreign SIP trunk, only local SIP works fine.
As a result, I'm not able to use the Twilio SIP trunk on 3CX. When I take a backup of 3CX and host it on an outside country network like
AWS or Digital Ocean it works fine.

Now I wonder if there is any way to set up proxy/VPN so that 3CX will connect Twilio SIP Endpoint through it?
In that case, I would use AWS or any other network to act as a proxy and add it to the Twilio setting, and later connect it on 3CX.
Thanks

Host in the cloud and use apps and the SBC to link yourself to the PBX. The tunnel uses port 5090 so your country shouldn't block that.

Obviously, I'm guessing this is not really legal.

Curious: what country? Sounds like India or China.

 

[amanjuman]

Host in the cloud and use apps and the SBC to link yourself to the PBX. The tunnel uses port 5090 so your country shouldn't block that.

Obviously, I'm guessing this is not really legal.

Curious: what country? Sounds like India or China.

I didn't get it properly.

Do you mean, Setup SBC on the outside country network and connect Twilio? (That didn't work)
Or set up 3CX outside the Country network and use SBC on the Country? It's not possible because I have a local trunk that can't be accessible outside the country network. So I must host 3CX on on-premises and connect Twilio somehow to receive calls from foreign customers.

and I'm talking about Bangladesh actually.

 

[Evolute IT]

So I must host 3CX on on-premises and connect Twilio somehow to receive calls from foreign customers.

In your case there's no way to do both. On-prem is okay, but Twilio won't work since your country will block it. And I am unaware of any way to bypass that. MAYBE using a cloud SBC to proxy the signaling and audio, but I cannot recommend it tho.

 

[amanjuman]

In your case there's no way to do both. On-prem is okay, but Twilio won't work since your country will block it. And I am unaware of any way to bypass that. MAYBE using a cloud SBC to proxy the signaling and audio, but I cannot recommend it tho.

"MAYBE using a cloud SBC to proxy the signaling and audio, but I cannot recommend it tho."

How to set up that, I know it's not recommended but I like to give it a try.

 

[SweetAction]

Another way you could do it is 2 3CX systems bridged together. One inside country and one outside. Then call rules to route between them.

 

[ChrisC_3CX]

Provided I understood the situation correctly and it goes something like this:

• Default SIP Port 5060 is not allowed as a destination.
• Your current SIP Trunk for local calls requires an on-prem PBX

The only thing I can think of is using two PBXs with a bridge configuration.

• The first PBX to be on-prem configured with the local SIP Trunk
• The second PBX to be in the cloud configured with the Twilio SIP Trunk
• Enable tunnel for the bridge or change the cloud PBXs SIP Port to something other than 5060 to get around the SIP Port restriction.

Note: To use bridges you need Pro or Ent license. The above provided that they are only blocking the port and not inspecting the actual traffic. If they are inspecting the actual traffic, using the 3CX tunnel might help but not necessarily.

 

[amanjuman]

Provided I understood the situation correctly and it goes something like this:

• Default SIP Port 5060 is not allowed as a destination.
• Your current SIP Trunk for local calls requires an on-prem PBX

The only thing I can think of is using two PBXs with a bridge configuration.

• The first PBX to be on-prem configured with the local SIP Trunk
• The second PBX to be in the cloud configured with the Twilio SIP Trunk
• Enable tunnel for the bridge or change the cloud PBXs SIP Port to something other than 5060 to get around the SIP Port restriction.

Note: To use bridges you need Pro or Ent license. The above provided that they are only blocking the port and not inspecting the actual traffic. If they are inspecting the actual traffic, using the 3CX tunnel might help but not necessarily.

Here whatever SIP port I use in local it doesn't work. I can't connect outside the SIP trunk, so they are doing it for traffic, and 5060 is always blocked from the outside the country network.

Now the problem is I have one Enterprise license outside the country network and another one is free. So I think both need to be pro or ent in order to use Bridge. So is there any other workaround for this case?

 

[ChrisC_3CX]

So is there any other workaround for this case?

I don't think there's another way. You could maybe sign up for a trial key, upgrade it to pro, have the pbx hosted in the cloud somewhere and perhaps even use a test IP trunk to test this out before committing to a purchase.

 

[amanjuman]

I don't think there's another way. You could maybe sign up for a trial key, upgrade it to pro, have the pbx hosted in the cloud somewhere and perhaps even use a test IP trunk to test this out before committing to a purchase.

What about a proxy? I saw an option in SIP Trunk name alternative proxy.

 

[ChrisC_3CX]

What about a proxy? I saw an option in SIP Trunk name alternative proxy.

A proxy in this case would only make sense if it were local to you. If you need to go through the IIG to reach it the traffic would still be blocked as it would have without the use of the proxy.

 

[amanjuman]

A proxy in this case would only make sense if it were local to you. If you need to go through the IIG to reach it the traffic would still be blocked as it would have without the use of the proxy.

My idea was set up a proxy outside the country network and use that proxy to connect Twilio inside the Country network.
So Proxy is able to talk to Twilio and 3CX is able to talk proxy.