XMPP WG Delta Between IETF 55 and IETF 56

This document summarizes the changes made to the XMPP Internet-Drafts between IETF 55 (Atlanta) and IETF 56 (San Francisco).

XMPP Core

The following changes were made to draft-ietf-xmpp-core:

• Fully specified the usage of TLS and SASL during stream negotiation, including client-to-server and server-to-server examples.
• Defined an extensible error-handling protocol for stream error conditions (to supersede the earlier use of CDATA error messages).
• Defined an extensible error-handling protocol for stanza errors (to supersede the HTTP-style error codes currently in use within the Jabber community).
• Specified the algorithm for generating values of the thread element.
• Clarified information regarding Unicode data and character encodings.
• Specified the optional use of the 'xml:lang' attribute on child elements that may contain natural-language CDATA (i.e., body and subject for messages, and status for presence), as well as the optional inclusion of multiple such elements as long as each is differentiated by a distinct xml:lang value.

XMPP IM

The following changes were made to draft-ietf-xmpp-im:

• Fully specified the interaction between rosters and presence subscriptions.
• Added information about the 'jabber:iq:privacy' protocol in order to meet requirements related to blocking communications in RFC2779.
• Added information about the 'jabber:iq:last' protocol in order to meet a requirement in RFC2779.
• Added a reference to vCard XML usage in order to meet two requirements in RFC2779.
• Brought error codes into line with changes to XMPP Core.
• Clarified a number of business rules regarding IM applications of XMPP.

Nodeprep

The WG published a new document, draft-ietf-xmpp-nodeprep, defining a stringprep profile for node identifiers in XMPP. It was desirable to publish a standalone I-D for this profile to ease registration of the profile.

Resourceprep

The WG published a new document, draft-ietf-xmpp-resourceprep, defining a stringprep profile for resource identifiers in XMPP. It was desirable to publish a standalone I-D for this profile to ease registration of the profile.

End-to-End Encryption

The WG published a new document, draft-ietf-xmpp-e2e, defining a basic mechanism for end-to-end encryption of message-related information. This I-D superseded the earlier appendix to draft-ietf-xmpp-core and addresses several security requirements in RFC2779. In particular, it improves upon the earlier appendix by encrypting the complete message stanza (not just the message body) and by including a unique id value to help prevent replay attacks.