If you already have an ATA in your possession, we probably support it for provisioning. The advantage is a quick and easy connection to babyTEL and we will push our fax settings provisioning file for your device, and we can manage the numbers on it very easily.
Send us an email to firstname.lastname@example.org and ask us about using your own device (i.e. Cisco SPA 112).
Provide us with the MAC address, and we will send you the information for getting it provisioned with us.
You will want to have access to its web-interface and then you will just need to copy paste a special link in one of your menus, and reboot the device for it to grab its connection.