Is Communication Between DFX and the Boundary Node Secure? How to Prevent Replay Attacks?

I am trying to better understand the security of the communication between dfx and the boundary nodes. Specifically:

  1. Is this communication secured with HTTPS/TLS, or is it plain HTTP?

  2. Are there any built-in protections against replay attacks or other security threats?

If the communication is not fully secured or if there are potential vulnerabilities, what measures can I take to protect my requests? Would using custom signatures, nonces, or additional layers of encryption help?

Any insights or recommendations would be greatly appreciated!

Between dfx and the boundary node we use HTTPS. Besides that there are a bunch of security features. For replay attacks we have request ids. This way an agent can figure out if the response was meant for that specific request or not.