[dns-operations] Monday rant againt the uses of the Public Suffix List

Stephane Bortzmeyer bortzmeyer at nic.fr
Mon Jan 21 11:54:20 UTC 2013

On Mon, Jan 21, 2013 at 03:45:36AM -0800,
 Jothan Frakes <jothan at gmail.com> wrote 
 a message of 171 lines which said:

> understanding what might be valid on the rightmost side of
> addresses.

Email addresses? If so, that's an extremely bad example. If you want
to test the *syntax* of an email address, just do like RFC 4287 and
use the regexp ".+ at .+". If you want to test the *content* of an email
address, send an email with a cookie. Everything else is broken by

> used by numerous software developers, programming languages,
> browsers (cookies), search engines, security software, and many
> other places.

And 95 % of these uses are bad ideas: it creates false positives
(.CW...) and false negatives (it's not because .COM exists that
anything.com has a meaning).

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