Knowledgebase: Support > VoIP
Configuring VoIP Providers Or SIP Trunks – 3CX
Posted by Daniel Naval on 11 May 2019 04:54 PM

VoIP Providers or SIP Trunks delivers telephone services and unified communications to customers who uses and are equipped with SIP Based PBX like 3CX.

Unified communications applications provides services like; voice calls, video conferencing, and web conferencing.

Requirements:

  • Supported VoIP provider (SIP Trunk)
  • Firewall tested and passed
  • Supported VoIP Provider
    • Easy Setup
    • Tested and passed by 3CX
    • Supported by 3CX Support
  • Generic VoIP Provider
    • Not tested by 3CX
    • No available 3CX Support
  • Provides Public Switched Telephone Numbers (PSTN)
  • Transmit via existing Internet Connection

Adding a Provider:

  • From Management Console, go to SIP Trunks
  • Click on Add SIP Trunk button
  • Choose Country and Supported Provider
  • Then set the Main Trunk Number

Note: This will act as “Catch All” for all non created DIDs for the trunk.

DID Inbound Rules:

  • Will route incoming calls to a destination that is based on the Dialed Number
    • Extensions
    • Voice Mail of Extension or Group
    • Forwarding to outside number
    • Fax Service
  • Different destinations will be based on
    • Time of the day
    • Holiday

Note: This will only add DIDs which do not follow the “Catch All” destination.

Adding DIDs:

  • From Management Console, go to SIP Trunks, Your Trunk, then click DIDs Tab and click on Add DID Button
  • Enter * + Last 6 DID Numbers
    • Sample DID No.: 001 333 1234567
    • Added DID No.: *234567
    • To save new DID, just click on “OK”

Adding Inbound DID Rules:

  • From Management Console, go to Inbound Rules and then click Add DID Rule
  • Set the name for DID
  • Pick DID from the Drop Down Menu
  • Then Point to Destination

Outbound Rules:

  • This is to allow and restrict called numbers
  • To select SIP Trunks basing on the criteria (as indicated below)
    • Destination number
    • Originating internal extension
    • Originating extension based on the Group Membership
    • Length of the dialed number

Adding Outbound Rules:

  • From Management Console, go to Outbound Rules and click Add
    • Set the Name and Criteria
    • Should start with Prefix: “0-9 and +”
  • Setting Outbound routes
    • There are 5 routes for the calls, the 2nd to 5th will be a backup and digits removed or added from each route.

Outbound Caller ID function:

  • You need to ask your provider for the Right Outbound Caller ID Format to use
    • Common EU formats: (this is to be used without spaces)
      • +44 555 1234567
      • 0044 555 1234567
      • 49 555 1234567
      • 0 555 1234567
      • 555 1234567
      • 1234567
    • Common US formats: (this is to be used without spaces)
      • +1 555 1234567
      • 1 555 1234567
      • 555 1234567
      • 1234567

Here are some common set-up errors that you may encounter and which needs to be checked to resolve the problem.

  • Outbound calls keeps dropping after 32 seconds
    • Active SIP ALG – needs to disabled from the firewall
    • Wrong Public IP address – needs to have the public IP address checked and replaced
    • Firewall Check NOT Passed – needs to perform Firewall Check and have all points to be GREEN (Passed)
  • One Way Audio Issue
    • Firewall Check NOT Passed – needs to perform Firewall Check and have all points to be GREEN (Passed)
    • Wrong Public IP address – needs to have the public IP address checked and replaced