[e2e] We do need anti-spam mechanism for e2e

[Michael B Greenwald]

   Wed, 07 Jan 2004 10:02:26 +0000
   Jon Crowcroft <Jon.Crowcroft at cl.cam.ac.uk>

   um, no - it doesnt cost you 22.57$ 
   
   what happens with a payment scheme is that we all put some real money in
   escrow  and we get some e-cash
   
   we use the e-cash to pay for sending to e2e, BUT remember who gets the
   e-cash? the members of the list do. so all members who participate get
   tokens (ecash) but unsolicted mail from outside gets a REAL bill. as we
   accrue real money, we can use it to put in escrow instead of our own
   money. after a while we start to profit from the spam, and we stop
   complaining all the time.
   
   end of problem.

It seems to me that the incentive mechanism you describe can't work.  

Won't anyone who sends more than 1 out of 2257 messages to the list
lose money, and not make a profit?  And if one actually *can* make a
profit by listening, then there is an incentive for people to
subscribe to the list simply to lurk (and have a filter drop all
messages without reading them).  As the number of lurkers rise, the
cost to send legitimate messages (as well as spam) rises too, and
makes it increasingly likely that sending even *one* message will cost
you money that will take receiving a *lot* of spam to recover from.
In other words, if legitimate but prolific senders can afford to send
to the list, then spammers can simply join the list and can also
afford to spam the list.  If legitimate senders can't afford to send,
then the list is dead (and I don't see how you can make it hard for
spammers to send if they are willing to join the list in some guise).

Maybe some more complicated incentives *could* work, (sending costs
more per recipient than the recipients receive? But then who collects
the excess money?  Or, maybe recipients can vote on the spam-level of
a message and senders that exceed some measure of off-topicality will
be kicked off the list before they recover their costs.  But that can
be defeated by joining with two accounts.  Maybe we delay the
repayment of real money to listeners by a sufficiently long time (or
bar withdrawl for some long time), so that the lost interest on the
real money is a disincentive, but immediately remunerate people with
e-cash.  That way, people who want to send must be willing to identify
themselves so that spammers are identified with a real address.  But
...).  Maybe something would work, but now we'd no longer have quite
so simple a scheme as you originally proposed...