The service allows businesses with few IT staff to set up spam and virus filtering which needs little maintenance but gives IT administrators control over company spam and virus policies.
Clara.net worked with supplier Checkbridge to develop its own system, which went live last month, after research showed it would be difficult to integrate managed filtering services such as MessageLabs and BlackSpider into its customer billing systems.
"Small businesses like it because it requires virtually no set-up. It takes an hour or so. Large companies like it because it is tiered. The site administrator can look after the site settings and say what is allowed in and what is not," said Neil Levine, Clara.net's group chief technology officer.
The system uses two open source virus scanners and Trend Micro's virus scanning engine. It uses the Cloudmark open source scanner to identify spam based on its structure rather than on key words.
"It looks for malformed header information, for example. This is a much better indication of spam that whether it contains the word Viagra," said John Turley, managing director of Checkbridge, who oversaw the development of the system.