SIP Trunk to Local Telephone Company

[RTC_Matt]

Hello,

I work for a small independent telephone company and we'd like to use 3CX as our PBX for our internal office staff. I would like to set up a SIP trunk from our phone switch SBC to a 3CX on premises dedicated PBX. Being the ILEC in our area I'd really prefer to not have to port our support numbers out to a VOIP provider. Is this possible, and if so, how?

We are also in talks with a third party call center to handle some of our overflow calls. If we did this we would want to connect to that third party call center's PBX (Asterisk based) via a dedicated SIP trunk. Is that possible?

I understand from the various support and forum articles that is recommended to only build SIP trunks to "Supported" VOIP providers, but that just doesn't really fit our use case.

Thanks,
Matt

 

[SweetAction]

Yes, both of these are possible as 3CX follows the SIP RFCs and is compliant.

3CX won't support it but you can do what you want to, and I'd expect you have the skillset to troubleshoot as needed.

FWIW our internal 3CX is connected to an AudioCodes SBC (similar to what you are proposing to do) as well as other PBXes/SIP Servers. Here's an old article on bridging to asterisk. https://web.archive.org/web/20161213151353/http://www.3cx.com/docs/bridging-asterisk-pbx/

 

[leejor]

I would like to set up a SIP trunk from our phone switch SBC to a 3CX on premises dedicated PBX.

Being the ILEC in our area I'd really prefer to not have to port our support numbers out to a VOIP provider. Is this possible, and if so, how?

If you are an ILEC, do you offer PSTN? If so then you would make use of an FXO gateway to connect PSTN lines to 3CX as trunks.
Here is the list to supported models.
https://www.3cx.com/voip-gateways/

Otherwise,if you are hosting yourself, then you should be able to get a bridge trunk working, even though these are now only supported to another 3CX PBX, with some help from that link.

 

[mmeier]

Hello,

I work for a small independent telephone company and we'd like to use 3CX as our PBX for our internal office staff. I would like to set up a SIP trunk from our phone switch SBC to a 3CX on premises dedicated PBX. Being the ILEC in our area I'd really prefer to not have to port our support numbers out to a VOIP provider. Is this possible, and if so, how?

We are also in talks with a third party call center to handle some of our overflow calls. If we did this we would want to connect to that third party call center's PBX (Asterisk based) via a dedicated SIP trunk. Is that possible?

I understand from the various support and forum articles that is recommended to only build SIP trunks to "Supported" VOIP providers, but that just doesn't really fit our use case.

Thanks,
Matt

Hey another Matt Telco

Yes, you can do this. How much you spend depends on scale.

Big guys like AudioCodes/Alcatel are great for enterprise deployments. They'll take whatever signaling you're getting and turn it into SIP/RTP. Last time Alcatel quoted me on an HA set up it was, er, eye-watering.

Smaller hardware solutions would be a multi-port ATA (or PRI) to SIP adapter from Grandstream or Digium (now Sangoma). They'll give you a SIP connection and are quite reliable. One of our emergency contact center customers uses a pair of Digium SIP-to-PRI devices to do the opposite of you (VoIP to legacy hardware), but the hardware can go either way.

Then you have open source solutions. FreePBX or SipWise NGCP will get the job done and cost you only set up time. FreePBX is Asterisk under the hood which is the mutli-tool of the voip world. NGCP is a gui for Kamailio/Asterisk/RTPproxy; little harder to configure, but designed for much higher volume. Either of these would get installed on a simple server with an analog or T1 you'd then configure.

Any of these will expose a SIP server and handle analog media for you. If it's just for you (for now) I'd spend the time learning SipWise or FreePBX. Both have carrier-level features that you might find useful for extending to your customers down the road.

All of this will plug-in to 3cx using the Generic Carrier template.