3CX SIP Trunk - Registration Settings

Use the following settings for registering/configuring a 3cx SIP Trunk:

General Tab

  • Trunk Details
    • Name: Lucid Technologies
    • Registrar/Server/Gateway Hostname or IP: {Your Service Domain}.21917.service
      • Port: 5060
    • Outbound Proxy: 21917.hpbx.outboundproxy.com
      • Port: 5060
    • Number of SIM Calls: {Enter The Number Of Simultaneous Calls}
  • Authentication
    • Type of Authentication: Register/Account based
    • Authentication ID (aka SIP User ID): SIP User
    • Authentication Password: SIP Password
      Note: Authentication ID and Password will be provided by Lucid Technologies

  • 3 Way Authentication: Uncheck
  • Route calls to
    • Main Trunk No: Caller ID/DID assigned (e.g. 9009991234)
    • Destination for calls during office hours: Extension (then choose extension from drop-down menu)
    • Destination for calls outside office hours: Extension (then choose extension from drop-down menu)


  • Numbers must be listed in 10 digit format. Do not include the 1

Inbound Parameters Tab

Note: The 3CX's template for our platform uses "From User" under Caller Name. This is to avoid an issue where calls to the PBX without a Display Name will show the Display Name as blanks on the phone. Otherwise, selecting "From: Display Name" will force the PBX to use the CID Name on the Display Name of the phones. Please use the setting that is appropriate for your setup.