On Aug 18, 2004, at 4:59 PM, <Atul(_dot_)Sharma(_at_)nokia(_dot_)com> wrote:
To dissuade spammers, we shall need a way to be able to identify
them direct or indirect.
Not necessarily. I agree that in practice most "anonymous" mail
really is traceable, i.e. "indirectly traceable," but you can make
tracing require rather more than a casual effort. More abstractly,
though, sender identification is only one of three major general
strategies that people are taking to fight spam:
-- identifying spam senders
-- filtering spam content
-- disrupting spam economics
I think most of us would agree that the second strategy, filtering, is
a running-in-place palliative rather than a solution, with Moore's Law
working against it. Unfortunately in most circumstances today it's
almost the only thing we have, which is why we're here trying to build
something else even while most of us explore ever-cleverer filtering as
well. Most of the non-filtering approaches, including MASS, are in the
"identifying senders" category, but I believe that the third (economic)
alternative has its value, particularly in facilitating anonymous mail.
There are still a wild variety of economically-oriented proposals, most
but not all of them nearly hopelessly implausible. Schemes that seek
to charge postage for every email message are a long way from reality,
but there are other approaches. At the ISP level, a simple metering
strategy can change the economics of spam originating with customers
who are either spammers or zombies -- simply give each email account an
outgoing mail quota, set generously enough to let any non-bulk mail
users just slip on by, and with special rules/mechanisms for mailing
lists. This requires no standards setting at all, and is being
implemented in primitive form by several mass market ISPs already.
Most interesting to me, however, is the use of computational challenges
for the purpose of "economic filtering" of spam. I'm willing to let
anyone in the world send me email if they're willing to invest, say, 60
CPU seconds in the effort, because I know it isn't worth it to
spammers. That's no big deal for legitimate users, although clearly
they'll prefer to avoid the 15 second penalty and use
authentication-based approaches when they aren't trying to be
anonymous. But such computational challenges are, to my mind, the key
technology that will permit us to preserve privacy in an era of
stricter spam control.
None of this places any limits on what we're trying to do in the MASS
group, but I'd prefer for us to try to view our authentication
mechanisms as part of a larger picture that preserves computational or
economic alternatives to sender identification. And I'd particularly
like to try to build a consensus understanding that anonymity *can* be
preserved in an era of spam control, rather than letting spam be used
as an excuse for killing off anonymity. -- Nathaniel