On the following wiki page it's boldly claimed that "A pre-shared public key also prevents man-in-the-middle attacks" https://en.wikipedia.org/wiki/Diffie–Hellman_key_exchange#Public_key : "It is also possible to use Diffie–Hellman as part of a public key infrastructure, allowing Bob to encrypt a message so that only Alice will be able to decrypt it, with no prior communication between them other than Bob having trusted knowledge of Alice's public key. Alice's public key is (g^a mod p, g, p). To send her a message, Bob chooses a random b and then sends Alice g^b mod p (un-encrypted) together with the message encrypted with symmetric key (g^a)^b mod p. Only Alice can determine the symmetric key and hence decrypt the message because only she has a (the private key). A pre-shared public key also prevents man-in-the-middle attacks."
I have my doubts. What do others think of 'MITM prevention by using public key encryption'? _______________________________________________ Messaging mailing list [email protected] https://moderncrypto.org/mailman/listinfo/messaging
