# SIP Trunk Interconnection Guide

## Here is the list of the most popular SIP PBX systems that have been tested and work very well with our SIP Trunk Gateway. 

#### PS: The list of Phone System PBX is in alphabetical order.  

| 3cx                          | [*3CX  configuration guide with DIDforSale SIP Trunk.*](https://docs.didforsale.com/sip-trunking/sip-trunking/3cx-configuration-guide)                                            |
| ---------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Allworx                      | [Allworx configuration guide with DIDForSale ](https://docs.didforsale.com/sip-trunking/sip-trunking/allworx)                                                                     |
| Asterisk                     | [Asterisk SIP Trunk Configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/asterisk)                                                                |
| Cisco UCM                    | [DIDForSale is Certified SIP Trunk provider for Cisco UCM](http://www.didforsale.com/wp-content/uploads/2023/12/didforsale-configuration-guide-cucm-sip.pdf)                      |
| FreePBX                      | [FreePBX SIP Trunk Configuration](https://docs.didforsale.com/sip-trunking/sip-trunking/freepbx-trunk-configuration)                                                              |
| Freeswitch                   | [DIDForSale SIP Trunking configuration with Freeswitch ](http://www.didforsale.com/wp-content/uploads/2023/12/Freeswitch_Interconnection_Guide.pdf)                               |
| FusionPBX                    | [FusionPBX Configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/fusionpbx)                                                                        |
| Go Autodial                  | [Go Autodial SIP Trunk Configuration with DIDForSale](http://www.didforsale.com/wp-content/uploads/2023/12/GoautoDial_Interconnection_Guide.pdf)                                  |
| Grandstream Devices \| UCMs  | [DIDForSale SIP Trunk works with all GrandStream Devices. ](https://docs.didforsale.com/sip-trunking/sip-trunking/grandstream-devices)                                            |
| Grandstream Cloud UCM PBX    | [grandstream-cloud-pbx](https://docs.didforsale.com/sip-trunking/sip-trunking/grandstream-cloud-pbx "mention")                                                                    |
| Hodusoft PBX System          | [HoduSoft PBX configuration with DIDForSale](#https-docs.didforsale.com-sip-trunking-sip-trunking-hodusoft-pbx-systemhere-is-list-of-most-popular)                                |
| Microsoft Skype for Business | [DIDForSale is a Certified SIP Trunk provider for Skype for Business](http://www.didforsale.com/wp-content/uploads/2023/12/Skype-for-Business-Server-SIP-Trunk-Configuration.pdf) |
| NEC Corporation              | [NEC Corporation configuration with DIDForSale](http://www.didforsale.com/wp-content/uploads/2023/12/NEC-SIP-Trunk-ProgrammingGuide-DIDforSale.pdf)                               |
| PBXinaFlash                  | [PBXinaFlas configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/pbxinaflash)                                                                     |
| Polycom OBI300               | [Polycom configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/polycom-obi300)                                                                     |
| Shoretel                     | [DIDForSale is a Certified SIP Trunk Provider for the Shoretel System](http://www.didforsale.com/wp-content/uploads/2023/12/DIDforSale_SipTrunk_Connection_with_Shoretel.pdf)     |
| Vital PBX                    | [Vital PBX Configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/vital-pbx)                                                                        |
| Yealink Phones               | [Yealink Phone configuration with DIDForSale](https://docs.didforsale.com/sip-trunking/sip-trunking/configure-yealink-phones)                                                     |
| Zycoo                        | [Configure Zycoo SIP Trunk with DIDForSale](http://www.didforsale.com/wp-content/uploads/2023/12/Zycoo_Interconnection_Guide.pdf)                                                 |

### Something you should know about SIP Trunk Pricing

Unlike many platform providers, DIDForSale does not charge for calls sent to SIP Trunks and is one of the very few providers who offer unlimited minutes of SIP Trunks. If you have not done so, check out [SIP Trunk Pricing](https://www.didforsale.com/sip-trunking-pricing)


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