By Allison Randal
The biggest thing I've wondered about spam is: Why do the spammers even bother? They spend an enormous amount of effort, time, and (I expect) money to deliver huge quantities of mail to my inbox, which I then spend an enormous amount of effort, time, and (for some people) money to delete unseen and unread. How is this profitable for the spammers?
Last week I talked to Ken Simpson and Stas Bekman of MailChannels, a spam-fighting solution provider. The answer to my question is that the business of spamming is profitable, sometimes enormously so, but it's a volume business and the percentage of profit over that volume is quite small. Spammers are the door-to-door salesmen who knock on every door in the neighborhood to get one sale. Except the neighborhood is the entire planet, and the number of doors they can knock simultaneously is only limited by the cost of computing power. That cost is the key point in the economics of spam: spammers have to get out a high enough volume of spam that the small sliver of profit is greater than the cost of sending it.
These economics drive the patterns of spam we receive. Traditionally porn advertisements have the highest click-through rate, followed by pharmaceutical advertisements, though penny stock spam is gaining popularity. And the spam messages that aren't advertisements, scams, or virus attacks, but just random strings of text? Ken Simpson comments, “Those messages are sent by spammers to poison the spam filters. When someone receives a message full of gibberish and reports it as spam, the spam filters tune themselves to recognize gibberish as spam—which reduces their overall accuracy.”
MailChannels has an interesting approach to the problem of spam. They use email traffic-shaping to identify the high-volume traffic patterns of spammers and then slow suspicious packets from those servers down to a crawl. In the short-term this affects the spam influx only on a local level: many spambots simply drop the connection to a slow mail server and move on to higher volume—and so more profitable—targets. (Like an animal taking a big bite out of a tasty-looking thistle, and then deciding it isn't worth the effort.) In the long-term, though, if enough mail servers employed similar tactics, the strategy has the potential to gradually disrupt the economics of spamming, making spam less profitable, or perhaps even unprofitable. [O'Reilly Radar]