RFC 8446, "The Transport Layer Security (TLS) Protocol Version 1.3", August 2018

Errata ID: 6123
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Ben Smyth
Date Reported: 2020-04-24
Verifier Name: Paul Wouters
Date Verified: 2024-03-29

Section 2 says:

The handshake protocol allows peers to negotiate a protocol version, select cryptographic algorithms, optionally authenticate each other, and establish shared secret keying material.

Notes:

Only client authentication is optional (albeit, server authentication is implicit for PSK-only key exchange mode)

Paul Wouters(AD): corrected with the following text:

The handshake protocol allows peers to negotiate a protocol version, select cryptographic algorithms, authenticate each other (with client authentication being optional), and establish shared secret keying material.

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