What is the protocol used for authenticating/encrypting Mac-to-Mac screen sharing?

The default Mac-to-Mac screen sharing uses VNC but obviously not the 开发者_如何学Pythonvanilla flavor as it uses both user+pass authentication (as opposed to password-only for regular VNC) as well as some encryption for the data.

What are these authentication and encryption protocols? Are there any libraries/modules/tools for Windows that support these protocols?

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according to documentation apple states that VNC supports Kerberos authentication. I don't know if any vanilla VNC clients support Kerberos authentication, but that may be a place to look.