We were recently updated by Roaring Penguin Software. The company sells software based on Linux and other UNIX-like operating systems. We were particularly interested in the company’s anti-spam offering, CanIt.
CanIt incorporates the usual cocktail of spam filtering techniques, including Bayesian content analysis, greylisting, and SPF. It’s based on the open source project, MIMEDefang.
One unusual and interesting aspect of CanIt is called Locked Addresses. This allows a user to create a unique alias for the exclusive use of a particular sender or domain. For example, if you want to give out your email address to a web site, you use CanIt’s web interface to create a new alias, telling it that the alias should only accept email from a single domain, or from a specific email address. CanIt rejects email sent by other domains. You don’t need to tell CanIt which domain to restrict receipt from — CanIt will assume that the first message received is from the intended domain. Simple, yet effective.