This two-page summary of the Brockmann & Company research The Spam Index Report discusses the methodology for determining the Spam Index, three applications of the proprietary method and recent findings comparing the Spam Index of eight anti-spam technologies.

Key findings

Challenge-response technology performed the best along three dimensions: Lowest Spam Index, most consistent Spam Index and highest user satisfaction with the email experience. ISP-based solutions were the worst performers.

Hosted processors and filter appliances categories came second and third in our study of over 500 business email users.