We've already talked about the three factors of authentication: something you know (e.g. a password), something you have (a passcard), and something you are (a fingerprint). Now Steve talks about the fourth factor of authentication: someone you know, or who knows you.
For 16Kbps versions, transcripts, and notes (including fixes), visit Steve's site: grc.com, also the home of the best disk maintenance and recovery utility ever written - Spinrite 6.
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