Choosing the right solution

After committing to deploy an antispam solution, you must choose among the four major types: client-based software, a third-party service, server-based software or an appliance.

Each type of solutions has advantages and disadvantages.

Client-based antispam software, such as those that come with e-mail applications such as Microsoft Corp. Outlook, are rather effective at blocking the majority of spam. Unfortunately, keeping client-based software updated can be a headache for IT staff. And such software solutions do nothing to keep spam from bogging down the servers in agencies and departments.

Third-party services MessageLabs Ltd and Postini Inc. relieve your agency's IT staff of update annoyances and don't require outlays for in-house hardware. Agencies and department officials, however, may be reluctant to run their e-mail traffic through third-party servers.

Enterprise-level antispam software packages, such as Sendmail Inc. Mailstream Manager and DigitPortal Software Inc. ChoiceMail, do not require additional hardware and offer agencies or departments complete control over the software and e-mail flow. The software resides behind firewalls but in front of e-mail servers, saving mail servers from inundation. The downside with software-only solutions is that they consume resources on the server running them and they require regular attention by the IT staff to ensure their security.

The final solution is antispam appliances, also known as e-mail firewalls. These solutions deliver antispam software — as well as antivirus software and other tools — in a dedicated appliance. Appliances offer the benefit of a turnkey service with few compatibility issues. They offer greater security since they generally run on their own stripped-down and thoroughly tested version of the Linux operating system, and unnecessary ports are shut down and unnecessary services are disabled.

The downside of appliances is that they are somewhat more costly. Since they are essentially black boxes, IT staffs must count on vendors for troubleshooting.