Archives for December 2003

Alan Ralsky, one of the biggest spammers, thinks the new CAN-SPAM act will hinder his spamming business, according to Saul Hansell’s story in today’s New York Times. Naturally, eventhing this guy says should be viewed skeptically, but the article is interesting nonetheless.

Mr. Ralsky talks a lot about himself in the article, and a revealing picture emerges. He has constructed a (rationalized) view of himself as a legitimate businessman who has been forced by those nasty antispam technologies to resort to practices like operating underground, forging mail headers, using open relays, and so on. Now the CAN-SPAM Act will ban some of those practices – and he wants us to feel sorry for him!

Mr. Ralsky also claims that he has been inactive (i.e., not spamming) for the past few weeks. I’ve been remarking to people for the last couple of weeks that there seems to be less spam than there was before. I almost wrote a blog entry asking all of you whether you had seen the same thing. Is it just the holiday season? Or is this one guy sending lots of my incoming spam?

Mr. Ralsky says he will soldier on, continuing to spam while complying with the new law. But he worries that his compliance will make it easier for people to filter out his messages. Let’s hope so.

The CAN-SPAM Act, signed into law yesterday by President Bush, will take effect on January 1. The Act asks the Federal Trade Commission to study whether a national do-not-spam list, akin to the much-loved do-not-call list, should be implemented. It’s an interesting question.

The crux of the problem is the danger that the do-not-spam list would become, in the hands of unscrupulous spammers, a who-to-spam list. We know that spammers pay money for lists of known-to-be-active email addresses. Surely, they would be more than happy to get such a list – and an unusually large and accurate one – from the government for free.

There are countermeasures, though. If we put some newly minted, fictitious addresses on the list, any mail sent to those addresses later must have involved misuse of the list. If we give out separate copies of the list to different spammers, we might put different fictitious addresses into each copy, so we can tell later whose copy was misused. Of course, spammers may collude and compare their copies to find the bogus addresses, so we want some of the bogus addresses to appear in multiple copies so that we have an idea of who to blame even if lists are combined. Figuring out how best to use duplicate bogus addresses for this purpose is a nice little exercise in theoretical computer science.

Some have suggested another approach, in which bulk emailers are given access to an “oracle” that will answer queries about whether a particular address is on the do-not-spam list. This could be done by providing an on-line service that answers queries, or by giving giving out cryptographic information (i.e., the cryptographic hashes of the addresses on the list) that allows address-by-address querying. In either case, the worry is that spammers will use the oracle to “purify” their address lists, by discarding addresses that aren’t on the do-not-spam list.

Another approach, perhaps ironically, is to provide a mailing service that will forward email to any recipient, except those on the do-not-spam list. Bulk emailers who used such a forwarding service would be able to send mail, via the service, to anybody who isn’t on the list, but they would have no easy way to test for membership of an arbitrary address on the list.

What’s the right answer? I don’t know. But I’m glad that we’re not rushing ahead with a list before we figure out how to do it or whether it’s a good idea in the first place.