I think I understand the concept of self-signature in GPG from reading the answer to this question. However it is not yet clear to me how check levels are assigned.
gpg --check-sigs one can see the list of signatures.
uid are self-signed and assigned a check level of 3 (
sig!3) meaning that an extensive verification of the key was performed. On the other hand, signatures on sub-keys contain no check level (
Why is that?
Are certificate check levels only assigned to
uid, since they are meant to link the id with a given master key. In that case, would a sub-key be validated by following the path
sub-key > master key > uid?
In that case, is it also true that I can never distribute my sub public key separately from the master public key itself? I envision a scenario where I could have multiple encryption keys (Is that even possible?) which I would distribute separately for different purposes.