I am trying to document ports, protocols and encryption used for a system diagram and am not sure how Pi communicates or encrypts the data on 5457. Thanks
For connections to port 5457, these are typically to the PI AF Server. Connections to the PI AF Server use the AF SDK and authenticate using Windows Integrated Security. Windows based transport security uses symmetric key encryption and hash based message authentication codes. The cipher algorithm is negotiated during logon. AES256-CTS-HMAC-SHA1-96 is typical for a Windows 7 Client with Active Directory. RC4-HMAC is expected with workgroup endpoints.
If you want some more information, you can take a look at this article for a more in depth discussion.
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