Sipcall Trunk registered, but no incoming. Port issue?

Dear community

Though my trunk is obviously connected, I cannot receive incoming calls.
Outgoing works good.

Name/username       Host              Dyn Forcerport Comedia  ACL Port     Status                  
501                 (Unspecified)     D   No         No        A  0        UNKNOWN                                  
502/502        D   No         No        A  5060     OK (29 ms)                               
SIPcall/413251xxxxx        Yes        Yes          5060     OK (40 ms)                               

When I connect the same account with a LinPhone, all works good.
The obvious difference: the port!

This is what the voip-provider sees as my registration:
Linphone/3.11.1 (belle-sip/1.6.1)
sip:[email protected]:62542;transport=udp

sip:[email protected]:5060;transport=UDP

While the Linphone uses some high port (62542), The PBX registers with 5060.
I have a strong suspicion, that either my sip-provider, or my internet provider will not allow inbound traffic on 5060. In the logfile, nothing can be seen, when I ring my number, at all.

How can I configure FreePBX to behave like the LinPhone (i.e. use a different port)?

Or what else could be the problem?
Could it be impossible to connect in trunk-mode to this free trial-account? (i.e. would I have to upgrade to a business-account first?)

Thank you for helping.

I’d start by troubleshooting this with the provider. They can tell you exactly why they are failing your inbound calls.

Also - it’s doesn’t pay to think of a call stream as a “two-way” conversation, especially during call setup. They are a pair of “one-way” connections, each with it’s own peculiar bits of network oddness. While your outbound may be working fine, your inbound could be blocked at any number of points along the way. Your VISP should be able to help you.

Thanks for advise.

I managed to convince the netopia-router to forward port 5060 to the asterisk-box - and all works like a charm.

I have two issues with this.

  • is it save (I believe, I read that it is a bit of a risk)?
  • why does my Yealink T42G NOT require port-forwarding when connected directly to the trunk?

As long as you use the Integrated Firewall and only allow you ITSP to contact your 5060 port, then you should be fine. Do NOT open your firewall up to the world.

because the phone is constantly checking for things like voicemail and registering to keep the line open. Asterisk (and by extension, FreePBX) only check when they need to, so the registration :“goes stale” and your number looks like it’s unreachable. Opening and forwarding your firewall ports is one simple way to deal with this.