Getting on top of junk mail

Sound email policies, along with proactive and reactive techniques, can cut spam down to a manageable level.

In February the European Union published a report on spam which estimated that it was costing internet users worldwide €10bn (£6.2bn) a year.

In April another study estimated that recorded deliveries of spam had risen from 700,000 in April 2001 to more than three million in February 2002.

Junk mail is more than just an irritation for most organisations. Consider the impact on network infrastructures.

According to Meta Group, between two and 10 per cent of inbound internet corporate email can be classified as spam, and that figure is expected to grow to between 10 and 20 per cent in the next five years.

When factoring in these additional messages, an organisation faces extra costs related to network hardware for storing and handling the messages and greater bandwidth costs for processing each message.

The impact on staff productivity must also be taken into account. Think of the time each employee spends managing spam at their desktop.

And a lot of this material can be considered offensive, as it often contains pornographic images and text laced with profanity. Such material can lead to issues related to harassment and legal liability.

Like virus creators, spammers have become increasingly sophisticated, while at the same time the solutions to the problem have grown increasingly complex.

However, the solution does not necessarily require a great deal of administration. Organisations can get spam under control in a number of ways.

Implementing sound email usage policies makes employees aware of their responsibility to prevent unwanted mail from entering the organisation, and shows them how to deal with spam that makes it to the desktop.

Also, reactive and proactive techniques, using a combination of blocking lists and content analysis, can identify spam senders and content at the gateway, while configuration tactics can fine-tune an organisation's gateway to ensure that every possible attempt is made to allow only business-relevant email.

A combination of techniques will maximise overall effectiveness and ensure that as much spam as possible is removed.

While these methods may overlap to some extent, using such approaches together can produce significant reductions in this annoying and expensive problem.

Pete Simpson is ThreatLab manager at Clearswift.