XEP-0267: Server Rosters

WARNING: Consideration of this document has been Deferred by the XMPP Standards Foundation. Implementation of the protocol described herein is not recommended.

Table of Contents

1. Description

In XMPP, rosters and presence subscriptions have been used to date only among IM users (see XMPP IM [1]). However, nothing prevents the application of these concepts to other XMPP entities, such as components and servers. Given that a presence subscription typically indicates some level of trust in a peer, server deployments can use the sharing of XMPP presence information as a way to indicate that a given server has a trust relationship with a peer server. The server might then share certain kinds of additional information only with trusted peers, for example Incident Reporting [2].

To establish a trust relationship with a peer, a server shall send a presence subscription request to the peer, just as is done between XMPP users.

Example 1. Service sends subscription request to peer

<presence from='montague.lit'
          to='capulet.lit'
          type='subscribe'/>
  

A server MUST NOT send such a presence subscription request unless explicitly requested to do so by the server administrator(s).

Upon receiving such a presence subscription request, the XMPP server software running at the peer MUST prompt the server administrator(s) to approve the request, rather than automatically approving it. Methods for doing so are out of scope for this specification.

If the server administrator(s) approve the request, the peer server shall then inform the originating server that the request has been approved.

Example 2. Peer sends approval to server

<presence from='capulet.lit'
          to='montague.lit'
          type='subscribed'/>
  

The peer SHOULD also send a subscription request to the originating server.

Example 3. Peer sends subscription request to server

<presence from='capulet.lit'
          to='montague.lit'
          type='subscribe'/>
  

If an XMPP server implementation supports this usage of presence subscriptions, it MUST keep a list of approved entities, which we denote a "server roster". The implementation MAY use that roster for access control purposes defined in other specifications.

2. Security Considerations

To follow.

3. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [3].

4. XMPP Registrar Considerations

This document requires no interaction with the XMPP Registrar [4].

Appendices

Appendix A: Document Information

Series: XEP
Number: 0267
Publisher: XMPP Standards Foundation
Status: Deferred
Type: Standards Track
Version: 0.1
Last Updated: 2009-04-30
Approving Body: XMPP Council
Dependencies: XMPP Core
Supersedes: None
Superseded By: None
Short Name: NOT_YET_ASSIGNED
Source Control: HTML
This document in other formats: XML  PDF

Appendix B: Author Information

Appendix C: Legal Notices

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 3920) and XMPP IM (RFC 3921) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.

Appendix E: Discussion Venue

The primary venue for discussion of XMPP Extension Protocols is the <standards@xmpp.org> discussion list.

Discussion on other xmpp.org discussion lists might also be appropriate; see <http://xmpp.org/about/discuss.shtml> for a complete list.

Errata can be sent to <editor@xmpp.org>.

Appendix F: Requirements Conformance

The following requirements keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".

Appendix G: Notes

Appendix H: Revision History

Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/

END