Does PPS Prevent Man-In-the-Middle Attacks?
Not by default. PPS uses underlying encryption mechanisms that allow users to verify their keys out-of-band using fingerprints, but again, by default PPS is not concerned with active attacks, but getting keys out there and in use. The great part is, once you have exchanged email with someone for weeks, you might decide to send something that’s sensitive. You call them on the phone, verify key fingerprints and then continue sending mail as always. No evesdropper can tell that your level of security was just increased unless they’re also tapping your phone. Traffic analysis becomes much less of an issue with PPS than without it.
