RFC 6120, "Extensible Messaging and Presence Protocol (XMPP): Core", March 2011

Note: This RFC has been updated by RFC 7590, RFC 8553

Errata ID: 3486
Status: Held for Document Update
Type: Editorial
Publication Format(s) : TEXT
Reported By: Marco Cirillo
Date Reported: 2013-02-18
Held for Document Update by: Gonzalo Camarillo

Section 5.4.1 says:

The receiving entity then MUST send stream features to the initiating
entity.  If the receiving entity supports TLS, the stream features
MUST include an advertisement for support of STARTTLS negotiation,
i.e., a <starttls/> element qualified by the
'urn:ietf:params:xml:ns:xmpp-tls' namespace.

It should say:

The receiving entity then MUST send stream features to the initiating 
entity.  If the receiving entity offers TLS capability, the stream 
features MUST include an advertisement for support of STARTTLS 
negotiation, i.e., a <starttls/> element qualified by the
'urn:ietf:params:xml:ns:xmpp-tls' namespace.

Notes:

Current text mixes up actual support of STARTTLS/TLS (which is mandated by section 5.2) with deployment/availableness of the said.

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