[ietf-dkim] end-users vs filtering engines

[Wietse Venema]

MH Michael Hammer (5304):
> Focusing on subdomains, I believe it may be useful for both senders and
> checking receivers if a domain were to be able to assert whether it's
> policy applies to all of it's subdomains. Given that we don't know how
> receivers or reputation services might utilize such an assertion, I
> would avoid must or should for a check at this stage.

How would a receiver discover the top-level domain given example.com,
example.ac.uk, example.org.au, etc.?

	Wietse