Novice question: setting up international service

Hi -

I was wondering if someone could outline the basic workflow for setting up the ability to have a UK number connected to my US-based Asterisk install.

I currently have a working freepbx system in the US, with 3 google voice lines configured - everything working great here.

Where i am confused is this:

I purchased a UK number through a sip service. Should i be requesting a trunk, sip forwarding, sip URI or a voip account?

I would prefer to not open ports on the firewall (if possible)

The overhead usage is very low - simply one incoming line is adequate.

Many thanks for any advice!

There are some subtle things that you are going to need to decide. For example, do you want to be able to call the UK and have your Caller ID be your UK number?

You want a trunk. All of the things you mentioned are SIP accounts, so you want that too.

Without knowing more about what kind of number you got, here’s how I’d set up your config:

  1. Set up a trunk that communicates with your SIP provider in the UK. You haven’t told us anything about your installation, so the specifics of that are going to be a little vague.

  2. If we assume you are using a Chan-SIP for your incoming SIP connections on port 5060, Set up your firewall to only allow this port to come from your SIP providers servers. This may be two or three (or eight) different addresses. You haven’t told us anything about your installation, so the specifics on that are going to be a little vague.

  3. If you are using an “ANY/ANY” incoming route, any calls that get delivered to your server will be picked up there. If you are using specific inbound DIDs to route traffic to different applications based on the incoming DID, setting up an “ANY/ANY” inbound will work for now. If you want to add a specific inbound route for your UK number, do so by checking the incoming calls is /var/log/asterisk/full and see what your provider is sending you.

  4. Set up an outbound route that recognizes UK numbers and only sends UK numbers out over that trunk.

Most of this stuff is easy to find out on the Internet - a Google search would have yielded everything I listed above in more detail that you could use.

1 Like

Dave - thank you that is an excellent resource and extremely helpful.

I have put in the hours googling! But the lack of knowledge in terminology had limited my effectiveness.

That outline is just what i needed.


FWIW the installation is Asterisk 11.23.0 on a raspberry pi - serving around 10 chan_sip extensions. 3 trunks to GV configured via the motif module in freepbx. This all behind a dynamic IP.

You’ve chosen a tough row to hoe.

Setting up DynDNS to handle your incoming calls is going to be critical to your success, and RasPBX is not exactly “the gold standard” way.

Still, plenty of people have done it. I suggest you get one thing working at a time; setting up something like this is like eating an elephant.

Best way to eat an elephant - one bite at a time!

I could have exchanged ‘Novice’ with ‘Hobbyist’ in the title and as such have the luxury of non-critical application which reduces the risk factor.

That being said the whole install is working smoothly with the international setup working great also now. Thanks to your guidance.

With regards to raspbx, for my use, it has been just great.

But my use is only ever subject to a maximum of two incoming calls at most, perhaps a door entry here and there. And as such the overhead requirement is low. The great config tools of FreePBX have not only been robust but very intuitive.
Anything beyond this type of install and i would go for a heftier server.

10 extensions, 2 door entries, multiple ring groups for incoming lines. All pretty vanilla but functioning smoothly.

An overnight image of the system every day in case of any disasters for added comfort.

Thanks again