In a couple of previous posts I was pointing out the types of convergent solutions possible with smart cards and USB tokens. These were reviewed on a project I was involved in that assessed a number of other strong authentication solutions.
One of these other technologies was Entrust IdentityGuard. This access solution has a number of features and capabilities, including low cost fob-style tokens, USB tokens, SMS, machine-based and ‘grid authentication’. This last solution type, grid authentication, uses paper cards with codes printed in rows and columns like bingo cards.
The primary advantages of grid authentication are low cost and ease of provisioning. Bingo cards are included in the price of the license (approx. $9/user per year) and can be distributed via mail or courier — or even fax or email if receipt can be assured. For companies with large numbers of users, bingo cards offer a significant cost saving — not just because of the cards are cheap but also due to the flexibility of distribution options.
The downside with bingo cards is that they are less secure than alternatives (such a fobs) as the three digits used in the solution are obviously fewer than most random OTP solutions. The cards can also be photocopied which exposes the solution to unique threats.
Bingo cards can work well for business-to-business applications where the frequency of use is low to moderate, and the level of data sensitivity is considered moderate.