[rfc-i] Drafting issue... use of MAY

John Levine johnl at taugh.com
Tue May 1 10:03:08 PDT 2018

In article <CAMm+LwgBFWW2GoemjDG3nVEO2=RLSH9XO3+uwRaQdi75oq=tyg at mail.gmail.com> you write:
>Quite often in a spec, I find myself writing something like this:
>A Frame MAY be either buffered or unbuffered...
>Frames are either buffered or unbuffered...

>Which is correct? I am thinking the second because it is not actually
>normative, it is by definition which is not the same thing.

I agree.  It is a good idea to reread RFC 2119 every once in a while
to remember what the words mean.

MUST doesn't mean "do this or die", it means "do this if you want to
interoperate."  MAY means there are different ways to do something all
of which will interoperate.

I find relatively few uses for MAY, but one of them would be "letters
in domain names MAY be in uppper or lower case."


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