What is CUDA 3bf863cc.pub ? what is 7fa2af80.pub ? Where do the magic alpha-numeric names come from?

Good afternoon,

Ref. some other sources, for example:

There seem to be 2 magic numbers / file names that get mentioned:

I can find some info alluding to these on the web, such as the above links, but I can’t find anything clearly explaining what they are or where they come from. Can somebody provide some background/overview on this?

Quick explanation of context:

I’m responsible for updating an installation script that has the following line in it:

nvidia_apt_key: http://developer.download.nvidia.com/compute/cuda/repos/ubuntu2004/x86_64/3bf863cc.pub

The person who originally set this up has left the company and I’m responsible for updating this. I have no idea what the 3bf863cc.pub is or if it should be updated.

I did notice that at Index of /compute/cuda/repos/ubuntu2004/x86_64 there are the 2 pub files available 3bf863cc.pub and 7fa2af80.pub but I still don’t know what these are or how to choose, or if I’ll ever need to update the above line at a later time. Please advise.