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Comment by throw0101c

2 hours ago

> How can Alice and Bob exchange their public keys securely? Not with Wireguard, because they'd need to already know each other's public keys for that! So they need to use some other secure mechanism as a bootstrap. Hence, out of band distribution.

I don't think this is quite equivalent: with public keys you 'just' have to establish authenticity, but with PSK you also have to worry about secrecy.

In someone ways it's similar to the PGP/GPG situation: initial secrecy is not the issue, trust is. If you trust someone's Twitter/Bluesky/Mastodon account, they could just the pubkey there; if you think e-mail is 'secure enough' to not be tampered with, they could e-mail you their pubkey. The threshold for 'PSK safety' is probably much higher.