Re: IMAP extensions needed for SPAM/HAM and WHITE/BLACK listing

[Nicolas Williams <Nicolas.Williams@xxxxxxx>]

On Sun, Jul 05, 2009 at 05:40:31PM -0700, Ned Freed wrote:
> 
> >On 3 jul 2009, at 1:05, George Michaelson wrote:
> 
> >> As an example, at the moment if I wish to inform google that I have
> >> known spam in local folders, I have to go to the web interface and
> >> manually tag. If there was an IMAP extension, I could review my
> >> local baysian junk folder, remove all non-spam (and flag the senders
> >> as white-listed if need be), and request the rest to be flagged as
> >> spam back on the IMAP backed MS.
> 
> >Doesn't moving the spam messages to the spam folder accomplish this
> >already? That's what my client does.
> 
> Please explain how moving a message to a random, arbtirarily named
> folder tells the server anything useful. People use all sorts of
> different naming schemes for folders, and it's common for clients to
> provide lots of flexibility in this area.

In particular the word 'spam' is really an English-language word.  L10N
would demand that the name of this folder not be 'spam' in all locales,
or at least that clients know how to map that folder name to the user's
language(s).  But even if we go for the latter, having special folder
names means denying or complicating the use of those names in other
languages for other purposes; it's bad enough we have one well-known
folder name (INBOX), let's have no more.

> The obvious way to make this work in IMAP is with a standardized
> folder annotation saying "messages put in this folder were flagged as
> spam". Then moves of messages to the folder with this annotation
> provide the server with the necessary information that this message is
> considered to be spam by the user. And by the same token, moving a
> message from this folder can be construed as the message not being
> considered spam after all.

+1

Or even just a message flag/annotation.  I understand the "move junk
mail to the junk mail folder" metaphor for flagging junk mail as such,
but one might want to flag junk mail and still move it to an "archived
mail" folder.  I don't find my argument for a per-message flag terribly
convincing, so I won't push it.

> It isn't perfect, but as long as this is taken as an indicator, not as
> an absolute statement, it should get the job done.
> 
> >But if you want this, I'd say that it needs to be a fractional thing,
> >not a binary spam/no spam indication. For instance, the server could
> >give something a spam score of 2 and the client also 2 and together
> >that would be 4 so the message is presumed to be spam (assuming the
> >spam threshold is 3), but in a binary system no spam OR no spam = no
> >spam.
> 
> There's a place for fractional scoring in spam filtering, but this isn't
> it. A user doesn't think "this message is 90% likely to be spam", they
> either think it's spam or it isn't.

+1

Fractional scoring by the server, or by software running on the client
can be useful, but the users themselves will generally make binary spam/
not-spam decisions.

Nico
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