There are numerous ways to set up IP phones with a PBX system. A common method is via Plug and Play (PnP) provisioning – where a phone announces itself via multicast on a local LAN. Phones can also be set up remotely via STUN (Session Traversal Utilities over NAT) and via a SBC (Session Border Controller). These methods typically utilise a PBX such as 3CX, to provide a configuration file that is generated by the system to give the phone its extension details. These methods are excellent provided a phone is supported and the networking in place is suitable. Sometimes an endpoint may need to be manually set up if it isn’t officially supported, or needs to connect directly to a SIP trunk (such as a small organisation with 1 or 2 phones).

Manual provisioning will always take longer to set up and is not ideal for anything beyond the odd individual phone. There are a few key details that persist across all vendor phones to connect directly to a SIP trunk. Here are a few common fields used, to manually register a phone against a PBX or SIP provider:

  • Account Name: a label for the account. This typically can be anything you like but should be meaningful e.g. Name and Extension number.
  • SIP Server: FQDN or IP address that the phone will connect to e.g. or
  • SIP User ID: typically the extension number, or a DDI number in the case of connecting directly to a SIP provider.
  • Authenticate ID: usually the extension number or a DDI number. This can vary between different providers and should be provided by the service you are connecting to.
  • Password: password to connect to your account. Always make this stronger and use a password manager such as LastPass, so you don’t need to enter a complicated password manually. Devices exposed to the internet are liable to be scanned by SIP bots and brute force attempts are guaranteed to be made. Reduce your attack surface with a strong password.
  • Re-register timeout: the frequency between re-registering to the account. Different SIP providers have different timeout values for security. Your SIP provider should provide these details.

These fields can also help ATAs (Analogue Telephony Adapters), legacy and end of life phones connect to modern PBX systems. They may not be able to use any advanced functionality, but they should be able to register and make calls. Are you facing issues with getting devices to register? Reach out to us!