Trend Micro is another familiar name in the anti-virus world. It has now branched out into email security with its InterScan Messaging Security Suite (IMSS), which, unsurprisingly, places a heavy emphasis on virus containment, but which also contains a number of other extremely valuable features.

IMSS is another spool-and-forward product, which means that the machine it is installed on should have a hard drive sufficient to handle your usual throughput of email. For this reason, and for reliability, it shouldn't really be installed on the SMTP server. Depending upon the needs of your network, it can be installed either in front of or behind your existing firewall, or even used in place of a firewall if - for some strange reason - you don't actually have one.

Considerable configuration is required, both during and immediately after installation. This might be quite a lengthy process, but the getting started guide is there to hold you hand at every stage. After installation, this is all carried out using the elegant web-based management console.

The next step is to define your organization's email policies. Using the policy manager, sender and recipient email addresses are specified and policy routes created. Depending on how the route compares with the content filters specified in the policy, one or more actions are then triggered. IMSS comes preloaded with filters, but you can easily define your own.

A lot of thought has been put into the anti-virus filter. If a virus is detected, you have the option of disinfecting, deleting or letting it pass. There is also a special option for mass-mailing viruses, where the program effectively fumigates the entire network.

Content scanning is provided by the eManager filter. This will look for pre-loaded and user-defined strings, phrases and keywords within emails and attachments, and take the appropriate action. Complex expressions can be specified using a set of operators, and there is also the option to block spam.

Trend has a good reputation for its anti-virus products, and for that reason the emphasis on viruses is understandable. If that is the major threat you perceive to your organization, this is well worth considering for your network. However, the content scanner, while workmanlike, is not as impressive as others in this Group Test.