ietf-mxcomp
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Re: Patent Application 683624

2004-09-16 23:29:03


On Thu, 16 Sep 2004, Douglas Otis wrote:

From their presentation, the concept was to impose about a 16 second
additional CPU message burden for the sender.  Their statement was such
additional overhead doubled the cost of equipment for the sender.  This
does not consider that many abusive senders control millions of Window
machines with hidden Trojan proxies and never pay for their use. 

And besides, the CPU  costs are rapidly going down with twice as fast CPUs
being released every one or two years. You simply can't rely on this 
technique - the hardware cost even for spammer that does not use zombie
machines is likely to be low percentage for cost of his operation - its 
the cost of hosting of such machine on "spam tolerant" network that is high.

It does bring up the issue of cost for a maximal 200 second receiver
burden for resolving Sender-ID or SPF records.  With a common spammer
technique of using random sub-domains, this will keep filters guessing
and the DNS resolvers scrambling for records. 

I note that the same problem exists with absolutly every proposal before
MARID. And in reality its not really proper concern for this group, we
need to worry how to properly identify GOOD senders and how to make sure
THEIR domains are not forged.

That spammers can still buy new domains for almost nothing ($6) or use 
subdomains which are technically free to them and then publish MARID 
records there is outside the scope of this group - it is something to be 
addressed by reputation.

It would seemi illegitimate senders win in any war of escalated 
overheads.  If only these innovators would properly handle a temp error, 
we could slow unknown senders without punishing legitimate senders. ; )

I did not understand how handling temp error would help. Can you explain
or give example?

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William Leibzon, Elan Networks:
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