What is the cost of spam to your SMB? This is a pertinent question, especially if you're having trouble convincing management to consider active measures -- beyond repeated presses of the delete key -- in the perpetual war against junk e-mail.
For assistance, you might want to check out the following quick and simple calculator from Google. Simply plunk in the figures such as number of employees, number of workdays per week, hourly wages, estimated amount of spam and seconds wasted per spam. Click on "Calculate!" and it will compute out the amount of productivity lost in dollars.
Check out the ROI calculator for spam here.
Of course, the ROI calculator was created to promote Google's own Message Security service. Even if you intend to use other solutions, however, I think it would be invaluable to be able to peg a dollar value to spam.
Assuming you were able to secure some form of budget to combat spam in your SMB, there are a number of approaches to spam filtering:
For additional information on anti-spam appliances and managed filtering services, be sure to check out my earlier blog on ways an SMB can implement spam filtering.
One consideration that I often see neglected when deciding on an anti-spam solution is the user-friendliness of the interface used to check for false positives. This is of vital importance, since even the finest algorithms will inevitably make mistakes, and users must be able to easily access e-mails tagged as spam in order to retrieve them.
Feel free to comment here if you have anything to add. Alternatively, you can drop me an e-mail if you have experience rolling out your own open source-based spam filtering solution. Look forward to hearing from you!