So I was thinking to myself in class last night while we were discuss various network security topics that email providers should digitally sign (with public-key encryption) their emails to verify that the emails aren’t being spoofed. I figure, one of the big problems with spam is spammers who spoof that they’re from some legitimate email domain (like yahoo, gmail, aol, etc.). Of course, I seem to be 2 months behind the curve, as Yahoo came up with DKIM (, which pretty does exactly that.