> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/use-cases/interoperability-examples/3cx.md).

# 3CX

Set up ProSBC between an ITSP SIP trunk and a 3CX server, covering SIP trunking, remote client access, phone provisioning and T.38 fax.

## Introduction

This Configuration Instruction describes how to set up a Telcobridges ProSBC for interworking between an ITSP’s SIP Trunk or remote client access for 3CX server.

### Prerequisites

* ProSBC devices must be installed as described in their respective with release 3.0.x/3.1.x. Release 3.0.x is not supported for TCP connections installation guides.
* 3CX.For additional information on 3CX, visit [3CX official web site](http://www.3cx.com/).

### Example Environments for SIPTrunking with 3CX

<figure><img src="https://3811773442-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiK3TemJSDhHz3xNMOvvk%2Fuploads%2FdtOeQinraQODAJ753BFM%2Fimage.png?alt=media&amp;token=195f9dac-5e2a-46b3-b711-d05b12922d40" alt="SIP trunking topology: an ITSP cloud connects through two ProSBCs in series to the 3CX server."><figcaption></figcaption></figure>

### Example Configuration

Step-by-step example SIP Trunk configuration.

* [Adding ProSBC as a SIP Trunk in 3CX Server](/configuration-details/configuration-by-use-case/3cx-phone-provisioning-configuration/configuration-for-3cx-pbx-server-with-the-prosbc-as-sip-trunk.md)
* [SIP Trunk Configuration Instruction with 3CX](/configuration-details/configuration-by-use-case/sip-trunking-configuration/sip-trunk-configuration-instruction-with-3cx.md)
* [T.38 Fax Configuration with 3CX](/configuration-details/configuration-by-use-case/3cx-phone-provisioning-configuration/configuration-for-3cx-pbx-server-with-the-prosbc-to-receive-t38-faxes.md)

### Example Environments for Remote Workers with 3CX

<figure><img src="https://3811773442-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FiK3TemJSDhHz3xNMOvvk%2Fuploads%2FCr297Mq9GVVBlT6U5g7L%2Fimage.png?alt=media&amp;token=70e49aac-a934-445d-ad32-0d77861e9348" alt="Remote workers topology: a remote office and two remote-worker phones reach the 3CX server across the internet through a single ProSBC."><figcaption></figcaption></figure>

### Example Configuration

Step-by-step example Remote workers configuration.

* [3CX Phone Provisioning Settings](/configuration-details/configuration-by-use-case/3cx-phone-provisioning-configuration.md)
* [Remote Workers Configuration Instruction with 3CX](/configuration-details/configuration-by-use-case/remote-workers/remote-workers-configuration-instruction-with-3cx.md)

### Troubleshooting

<table><thead><tr><th width="200">Call Trace</th><th width="200">Test Call</th><th width="200">TBReport</th><th width="200">Advanced Troubleshooting of ProSBC</th></tr></thead><tbody><tr><td><ul><li><a href="/troubleshooting-and-support/troubleshooting-tips-and-actions/configuring-call-trace.md">Configure call trace</a></li><li><a href="/troubleshooting-and-support/troubleshooting-tips-and-actions/configuring-call-trace/retrieving-call-trace.md">Retrieve call trace</a></li></ul></td><td><ul><li><a href="/troubleshooting-and-support/troubleshooting-tips-and-actions/creating-a-test-call.md">Creating a Test Call</a></li></ul></td><td><ul><li><a href="/troubleshooting-and-support/troubleshooting-tips-and-actions/tbreport.md">Capture a report of the system</a></li></ul></td><td><ul><li><a href="/troubleshooting-and-support/troubleshooting-common-problems.md">Advanced Troubleshooting of ProSBC</a></li><li><a href="https://docs.telcobridges.com/wiki/FreeSBC:3CX:CSTA_Calls_never_ends">CSTA calls never ends</a></li></ul></td></tr></tbody></table>


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