Private Cloud Encrytion

I am willing to share encrypted files between a RaspberryPi and one of my servers (no AWS).
I wonder how to use lock feature with shared_key=cloud. API docs talks about “Zymbit cloud”, what are the requirements for a Zymbit cloud server?.

I don’t mind if I have to use another Zymkey module to cipher, in fact I like the idea, but how do I obtain this key?

I assume it is not the safest but safe enough for a scenario where Raspberry must be able to read files encrypted remotely and private-public key is too complex to build and test (private key should be at the remote server where files to encrypt are built).

Zymbit used to maintain a cloud service about 1.5 years ago, but it is no longer supported.

It would be possible to do what you want to do with ECIES or even Diffie Hellman key exchange. However, these features are not currently available with the Zymkey 4i. They are planned features for our new product.

In the meantime, it might be possible to do a custom implementation of ECIES where the keys are stored on a Zymkey/LUKS encrypted volume.

Ok, sad to hear that. I think it was a very nice feature.
Anyway I will do as you suggest with some other software.

Will Zimbit release the software that runs the cloud? It will be nice if we can self-host it.

We have no immediate plans to release our legacy cloud software into the open domain. Primarily for reasons of not creating a support burden at this time.

Right now we are focussed on compatibity with 3P cloud vendors like AWS_IOT and MS_Azure.