Does Backbone communicate via an encrypted channel?

Question

When synchronizing between Jira projects, does Backbone communicate via a secure, encrypted channel?

Yes, Backbone uses these secure channels for communication:

In a synchronization to server/data center to cloud or local, you can configure the projects to communicate via http(s)
In a synchronization to server/data center (behind firewall), you can encrypt the files and emails using PGP

You can read more about it on the page Data Encryption.