Unit – SIP Phones and Registration

Fastcall devices in more detail

A device in Fastcall is used to make outbound and receive inbound calls. Fastcall supports adding a SIP phone as a user device.

You can set up multiple devices in Fastcall and choose which ones to use – you might have your desk phone, your personal mobile, etc. Check this page for more info on SIP phones.

Receive an inbound call on a SIP phone

  1. Fastcall rings your SIP phone.
  2. When you pick up you are connected.
  3. The experience is different that using the Fastcall softphone.

Device settings

Devices are controlled from the settings menu, under My Settings > Devices.

Devices Setting

SIP Registration

The Server / SIP Outbound Proxy configuration will be set Twilio by Fastcall.


There are a few steps to be completed:

  1. Fastcall creates a new SIP Domain in the subscriber’s Twilio subaccount and enables SIP Registration
  2. Fastcall will give you the user name, PW and SIP URI
  3. Configure your SIP-enabled phone to register with Twilio.

Add the SIP phone as a device in Fastcall

Here there is a guide from Twilio using a Polycom as an example: https://www.twilio.com/docs/documents/4/PolycomVVX400CfgGuideVer1_0.docx.pdf

After your phone is configured, all you need to do is to add the number as a “Device” under “My Settings” You do not need to add the user name or PW in Fastcall. These are added in the phone.

Additional devices

Where the “Number” field would be something like: sip:phonenumber@yourdomain.​sip.r​egion.​twilio.com

Once you have added the SIP device, you are able to use it from the Fastcall widget for outbound calls, this will work as click-to-call, calling the SIP phone first, when answered it will connect the called party.

For inbound calls, you can add a new “Inbound Route” under “Inbound Routing”, using this new SIP device as the target.

Important settings in your phone:

NAT Mapping Enabled
NAT Keep Alive Enabled
SIP Transport = TCP
SIP Port 5061
Register – YES

SIP URIUser name / PW

Using devices

Once you’ve added a device, it will be available in the Widget so you can pick it for making an outbound call. It will also be available for use in inbound routing.

Your administrator can restrict the devices available to you in the Widget

Last updated: 2022-06-02, Fastcall version 7.62