ObiNet Provisioning Security

[AtLinkW]

I apologize if this is a duplicate post, but I checked 10 pages of topics pertaining to this and couldn't find what I was looking for. That being said, is the provisioning done by ATAs to the ObiTalk/ObiNet server secured via HTTPS or SFTP or the like and is it encrypted or plain text?

Thank you in advance for your time.