Federal Internet Law & Policy
An Educational Project

Email : SPAM Notes

Dont be a FOOL; The Law is Not DIY

Economics :: Cost of Spam

"In a 2002 survey on the commercial use of e-mail, it was estimated that the cost to send a single e-mail averages USD 0.05 with a low value of USD 0.01.12 Other research has suggested that it costs 0.00032 cents to obtain one e-mail ad dress.... With low costs, low response rates will show a profit through spam nonetheless. According to a survey conducted by Mailshell in March of 2003, more than 8% of the 1 118 respondents admitted that they have actually purchased a product promoted via spam. A study by the Wall Street Journal in 2002 showed that a return rate as low as 0.001% can be profitable when using e-mail. In one case cited, a mailing of 3.5 million messages resulted in 81 sales in the first week, a rate of 0.0023%. Each sale was worth USD 19 to the marketing company, resulting in USD 1 500 in the first week. The cost to send the messages was minimal, probably less than USD 100 per million messages. The study estimated that by the time the marketing company had reached all of the 100 million addresses it had on file, it would probably have pocketed more than USD 25 000 on the project."  OECD Background Paper For the OECD Workshop on SPAM   DSTI/ICCP(2003)10/FINAL page 9  Jan 22, 2004

Cost of Hoaxes and Spam

While these hoaxes may appear benign, there is a considerable and measurable cost, one that network operators know first hand. The cost for transmitting a single email through a network may be essentially free. The bits pass through the communications pipe barely noticed. The cost, however, of transmitting a million emails through a pipe can show up on the budget. Network operators, facing onslaughts of email are faced with choices: they can let the email flood over whelm their pipes, dropping packets here and there, good packets with the bad, resulting in the equivalent of a denial of service attack on their network - losing customers who are annoyed about their emails vaporizing - or they can spend a lot of money over building their networks in anticipation of peak load, passing the costs of this excess capacity onto the consumer.

Hoaxbusters [Hoaxbusters, Information About Hoaxes] has a very interesting analysis of the cost of hoax emails. If everyone on the Internet were to receive one hoax message and spend one minute reading and discarding it, the cost would be something like:

50,000,000 people * 1/60 hour * $50/hour = $41.7 million

Think of it another way. What if everyone who received a hoax email sent it onto 10 people, who then sent it on to 10 people, and so on, and so on, and so on..








Number of messages







Within 6 generations of the hoax (it being passed along 6 times), the number of messages generated would be up to one million! The load on the networks for this traffic is considerable - the network must either indiscriminately drop traffic or invest in capacity. Either way, it is a cost.

SPAM Tactics

Spam Techniques

Anti SPAM Techniques

IP Based
  • SPF
  • Domain Keys
  • DKIM - Domain Keys Identified Mail
  • Approved by IETF as a standards track protocol RFC 4871
  • IETF Working Group
  • Provides signature based authentication of email messages
  • Soon available in a wide variety of vendor products
  • Deployed by Google, CISCO
  • Can create white list and deal with false positive problem in whitelist that are otherwise authenticated. Gives you reliable domain name identification system. Deters use of well-known phisher domains by cybercriminals.
  • Note that cybercriminals can authenticate their messages too.
  • © Cybertelecom ::