Frank Ellermann wrote:
Tony Hansen wrote:
table of possible policies:
sending mail signature 3rd party current
1 allowed unspecified unspecified NONE
2 allowed never never
3 allowed never allowed
4 allowed optional never ?/WEAK
5 allowed optional allowed ~/NEUTRAL
6 allowed always never !/EXCLUSIVE
7 allowed always allowed -/STRONG
8 never ./NEVER
9 user ^/USER
Nice table, thanks. Are #2 / #3 the same as "no key" ?
How does a 3rd party detect what it should be, 2 or 3 ?
Hmmm, I see an ambiguity in how I was thinking about the possible
policies. When I wrote #2 and #3 above, I was thinking in my mind that
#2 says you will never ever get a message with a signature.
#3 says you will never get a message directly with a signature,
but you may get one from a 3rd party.
but that's not how the signature axis was defined. So it's probable that
#2 and #3 *should* be collapsed into the single item, as you suggest below:
2 -signature,-3ps signature=never,3ps=never
3 -signature,+3ps signature=never,3ps=allowed
If we could get rid of #3 somehow it should be simple,
"never" always terminates a policy:
o mnemonic mail signature 3rd party your
NONE other n/a n/a #1
. NEVER never n/a n/a #8
^ USER maybe other n/a #9
maybe never n/a #2
? WEAK maybe maybe never #4
~ NEUTRAL maybe maybe maybe #5
! EXCLUSIVE maybe always never #6
- STRONG maybe always maybe #7
In the spirit of ".", "!", and "?" maybe your case #2
could use ":".
And the mnemonic would be "NOSIG", eh?
All fodder for thought.
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