My friend Fred Avolio (who has helped me host my Web Informant mailing list for several years), has put together a master class that will teach even the most experienced IT person the important fundamentals of network security. (And I say this even with him plugging my first book on Internet Messaging.) What I like about Fred is that he has tremendous wisdom and perspective, and shows the reader some old stuff that is still very much au courant. This post is well worth a deep dive.