Computer security analysts who fight spam face the same thankless task as goalkeepers: They don't get much credit for the unsolicited e-mail they stop, only demerits
for the ones that get through.
But those few messages that wriggle past increasingly sophisticated filters constitute the greatest threats on the Internet.
The messages range from relatively harmless pitches for human growth hormones to ones with malicious code attached that could
steal passwords or documents from a machine.
The sheer volume of spam still threatens to bring the Internet to a crisis point. Figures are difficult to gauge, but the
amount of spam has crept upward in recent years. The forecast isn't good, either.
"We see spam just going up to the point where Internet servers start having difficulty," said Steven Linford, CEO of Spamhaus,
a London nonprofit organization that generates a list used by technology companies and organizations running e-mail servers
to block spam.
"Spam will tend to increase to where it will be 99% of all e-mail on the Internet," he said. "At that point, governments will
start to take notice."
The front line of defense for most computers connected to the Internet is antispam software that tries to determine whether
a message is legitimate. Antispam software uses a number of methods to make that decision.
The software can block messages coming from a particular IP address of a computer known to send spam. Messages containing
links to potentially harmful Web sites can be halted using URL filtering. Security vendors can tweak special "rules" for their
antispam engines, such as blocking messages containing certain kinds of text identified as common to spam.
The IDG News Service is a Network World affiliate.
