ForeFront was the marketing name for a suite of Microsoft Line of business applications. The suite contained products to protect networks and Microsoft server products such as Exchange, Lync, and SharePoint from attack. All but three of the products in the suite have been discontinued. Only the identity manager, the endpoint protection product, and ForeFront protection for Exchange are still developed. But not under the ForeFront name. The major product in the suite was Threat Management Gateway (TMG). A very popular product that can be replaced with a LoadMaster solution as outlined in this KEMP article.