why "penny black" etc. are not very useful

[Ben Laurie]

Perry E. Metzger wrote:
> In my opinion, the various hashcash-to-stop-spam style schemes are not
> very useful, because spammers now routinely use automation to break
> into vast numbers of home computers and use them to send their
> spam. They're not paying for CPU time or other resources, so they
> won't care if it takes more effort to send. No amount of research into
> interesting methods to force people to spend CPU time to send mail
> will injure the spammers.

If you set the price to 1 minute of CPU, and spammers own 10% of all 
machines on the 'net, then the average machine can only receive 144 
spams per day. That's a significant improvement on my situation.

Plus I'd've thought that having 100% CPU utilisation all the time might 
attract attention. But maybe not.

Cheers,

Ben.

-- 
http://www.apache-ssl.org/ben.html       http://www.thebunker.net/

"There is no limit to what a man can do or how far he can go if he
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