About Debra Shinder (WindowsSecurity.com)

Application Layer Filtering (ALF): What is it and How does it Fit into your Security Plan?

ALF, not a nickname for Alfred but an acronym for Application Layer Filtering, is one of the hottest new buzzwords in a jargon-laden security subfield: firewall technology. Firewall vendors are rushing to implement ALF into their firewall products, and/or beefing up their ALF implementations to compete with those of other vendors. But exactly what is ALF and is it a “must have” feature to look for when you buy a firewall, or just another bit of marketing hype?