Comment 28 for bug 1988819

I did not make any changes to the design when moving it from Update-Manager in apt, it's been this way for 10 years now, it's a proven concept.

The initial implementation used and md5 but the math gets complex when dealing with 128 bit integers.

You can easily override the machine-id for apt by setting the apt.conf option, /etc/machine-id is a default. It's general consensus that everything should be using the same machine id though.