XEP-0387: XMPP Compliance Suites 2018

NOTICE: This document is currently within Last Call or under consideration by the XMPP Council for advancement to the next stage in the XSF standards process. The Last Call ends on 2017-12-21. Please send your feedback to the standards@xmpp.org discussion list.

1. Introduction
2. Compliance Levels
    2.1. Core Compliance Suite
    2.2. Web Compliance Suite
    2.3. IM Compliance Suite
    2.4. Mobile Compliance Suite
3. Implementation Notes
4. Security Considerations
5. IANA Considerations
6. XMPP Registrar Considerations
7. Acknowledgements

Appendices
    A: Document Information
    B: Author Information
    C: Legal Notices
    D: Relation to XMPP
    E: Discussion Venue
    F: Requirements Conformance
    G: Notes
    H: Revision History

1. Introduction

The XMPP Standards Foundation (XSF) [1] defines protocol suites for the purpose of compliance testing and software certification. This document specifies compliance levels for XMPP clients and servers; it is hoped that this document will advance the state of the art, and provide guidance and eventual certification to XMPP client and server authors. Unless explicitly noted, support for the listed specifications is REQUIRED for compliance purposes. A feature is considered supported if all comma separated feature providers listed in the "Providers" column are implemented (unless otherwise noted).

2. Compliance Levels

2.1 Core Compliance Suite

Table 1: XMPP Core Compliance Levels

Feature	Core Server	Core Client	Advanced Server	Advanced Client	Providers
Core features	✓	✓	✓	✓	RFC 6120 [2], RFC 7622 [3]
TLS	✓	✓	✓	✓	RFC 7590 [4], SRV records for XMPP over TLS (XEP-0368) [5] [6]
Feature discovery	✓	✓	✓	✓	Service Discovery (XEP-0030) [7]
Feature broadcasts	✕	✓	✓	✓	Entity Capabilities (XEP-0115) [8]
Server Extensibility	✓	N/A	✓	N/A	Jabber Component Protocol (XEP-0114) [9]
Event publishing	✕	✕	✓ [10]	✓	Personal Eventing Protocol (XEP-0163) [11]

2.2 Web Compliance Suite

To be considered XMPP web compliant, all features from the core compliance suite must be met, as well as all features in this suite.

Table 2: XMPP Web Compliance Levels

Feature	Core Server	Core Client	Advanced Server	Advanced Client	Providers
Web Connection Mechanisms	✓ [12]	✓ [13]	✓ [12]	✓ [13]	RFC 7395 [14], XMPP Over BOSH (XEP-0206) [15] (See also: BOSH (XEP-0124) [16])

2.3 IM Compliance Suite

To be considered XMPP IM compliant, all features from the core compliance suite must be met, as well as all features in this suite.

Table 3: XMPP IM Compliance Levels

Feature	Core Server	Core Client	Advanced Server	Advanced Client	Providers
Core features	✓	✓	✓	✓	RFC 6121 [17]
User Avatars	N/A	✓ [18] [19]	N/A	✓ [18] [19]	User Avatar (XEP-0084) [20]vCard-Based Avatars (XEP-0153) [21]
vcard-temp	✓	✓ [18]	✓	✓ [18]	vcard-temp (XEP-0054) [22]
Outbound Message Synchronization	✓	✓	✓	✓	Message Carbons (XEP-0280) [23]
User Blocking	✕	✕	✓	✓	Blocking Command (XEP-0191) [24]
Group Chat	✓ [12]	✓ [25]	✓ [12]	✓ [25]	Multi-User Chat (XEP-0045) [26] [27], Direct MUC Invitations (XEP-0249) [29]
Bookmarks	✕	✕	✓ [12]	✓	Bookmark Storage (XEP-0048) [30]
Persistent Storage of Private Data via PubSub	✕	✕	✓ [12]	✓	Best Practices for Persistent Storage of Private Data via Publish-Subscribe (XEP-0223) [31]
Private XML Storage	✕	✕	✓ [12]	✓	Private XML Storage (XEP-0049) [32]
Session Resumption	✕	✕	✓	✓	Stream Management (XEP-0198) [33]
Stanza Acknowledgements	✕	✕	✓	✓	Stream Management (XEP-0198) [33]
History Storage / Retrieval	✕	✕	✓	✓	Message Archive Management (XEP-0313) [34]
Chat States	N/A	✕	N/A	✓	Chat State Notifications (XEP-0085) [35]

2.4 Mobile Compliance Suite

To be considered XMPP mobile compliant, all features from the core compliance suite must be met, as well as all features in this suite.

Table 4: XMPP Mobile Compliance Levels

Feature	Core Server	Core Client	Advanced Server	Advanced Client	Providers
Session Resumption	✓	✓	✓	✓	Stream Management (XEP-0198) [33]
Stanza Acknowledgements	✓	✓	✓	✓	Stream Management (XEP-0198) [33]
Client State Indiciation	✓	✓	✓	✓	Client State Indication (XEP-0352) [36]
Third Party Push Notifications	✕	✕	✓ [12]	✓	Push Notifications (XEP-0357) [37]

3. Implementation Notes

Some of the protocol specifications referenced herein have their own dependencies; developers need to consult the relevant specifications for further information.

4. Security Considerations

This document introduces no additional security considerations above and beyond those defined in the documents on which it depends.

5. IANA Considerations

6. XMPP Registrar Considerations

7. Acknowledgements

The author would like to thank Guus der Kinderen, Dele Olajide, Marc Laporte, Dave Cridland, Daniel Gultsch, Florian Schmaus, Tobias Markmann, and Georg Lukas for their suggestions.

Appendices

Appendix A: Document Information

Series: XEP
Number: 0387
Publisher: XMPP Standards Foundation
Status: Proposed
Type: Standards Track
Version: 0.4
Last Updated: 2018-01-25
Approving Body: XMPP Council
Dependencies: RFC 6120, RFC 6121, RFC 7395, RFC 7590, RFC 7622, XEP-0030, XEP-0045, XEP-0048, XEP-0049, XEP-0084, XEP-0085, XEP-0114, XEP-0115, XEP-0124, XEP-0163, XEP-0191, XEP-0198, XEP-0206, XEP-0223, XEP-0249, XEP-0280, XEP-0313, XEP-0352, XEP-0368
Supersedes: XEP-0375
Superseded By: None
Short Name: CS2018
Source Control: HTML
This document in other formats: XML PDF

Appendix B: Author Information

Sam Whited

Email: sam@samwhited.com
JabberID: sam@samwhited.com
URI: https://blog.samwhited.com/

Jonas Wielicki

Email: jonas@wielicki.name
JabberID: jonas@wielicki.name

Appendix C: Legal Notices

Copyright

Permissions

Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the "Specification"), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specification, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or substantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or publisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation.

Disclaimer of Warranty

## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ##

Limitation of Liability

In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall the XMPP Standards Foundation or any author of this Specification be liable for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if the XMPP Standards Foundation or such author has been advised of the possibility of such damages.

IPR Conformance

This XMPP Extension Protocol has been contributed in full conformance with the XSF's Intellectual Property Rights Policy (a copy of which can be found at <https://xmpp.org/about/xsf/ipr-policy> or obtained by writing to XMPP Standards Foundation, P.O. Box 787, Parker, CO 80134 USA).

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 6120) and XMPP IM (RFC 6121) 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.

Given that this XMPP Extension Protocol normatively references IETF technologies, discussion on the <xsf-ietf@xmpp.org> list might also be appropriate.

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

1. The XMPP Standards Foundation (XSF) is an independent, non-profit membership organization that develops open extensions to the IETF's Extensible Messaging and Presence Protocol (XMPP). For further information, see <https://xmpp.org/about/xmpp-standards-foundation>.

2. RFC 6120: Extensible Messaging and Presence Protocol (XMPP): Core <http://tools.ietf.org/html/rfc6120>.

3. RFC 7622: Extensible Messaging and Presence Protocol (XMPP): Address Format <http://tools.ietf.org/html/rfc7622>.

4. RFC 7590: Use of Transport Layer Security (TLS) in the Extensible Messaging and Presence Protocol (XMPP) <http://tools.ietf.org/html/rfc7590>.

5. XEP-0368: SRV records for XMPP over TLS <https://xmpp.org/extensions/xep-0368.html>.

6. Server support means having the ability to accept direct TLS connections.

7. XEP-0030: Service Discovery <https://xmpp.org/extensions/xep-0030.html>.

8. XEP-0115: Entity Capabilities <https://xmpp.org/extensions/xep-0115.html>.

9. XEP-0114: Jabber Component Protocol <https://xmpp.org/extensions/xep-0114.html>.

10. While 'Personal Eventing Protocol' does not require all the features of 'Publish-Subscribe' to be available on the users' JIDs, and nor does this suite, it is desirable for this to be the case and it is expected that this will a requirement of future Compliance Suites.

11. XEP-0163: Personal Eventing Protocol <https://xmpp.org/extensions/xep-0163.html>.

12. Support can be enabled via an external component or an internal server module/plugin. If claiming compliance using such an addition, the necessary components/modules/plugins MUST be detailed.

13. Only one of the recommended providers must be implemented for compliance.

14. RFC 7395: An Extensible Messaging and Presence Protocol (XMPP) Subprotocol for WebSocket <http://tools.ietf.org/html/rfc7395>.

15. XEP-0206: XMPP Over BOSH <https://xmpp.org/extensions/xep-0206.html>.

16. XEP-0124: Bidirectional-streams Over Synchronous HTTP <https://xmpp.org/extensions/xep-0124.html>.

17. RFC 6121: Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence <http://tools.ietf.org/html/rfc6121>.

18. Not required for command line or terminal based interfaces.

19. While 'User Avatars' is more modern, 'vCard-Based Avatars' is more widely deployed. Although it is suggested that to maximise interoperability with existing software a client fully supports both it is sufficient to claim compliance with this suite if the support for 'vCard-Based Avatars' is read-only.

20. XEP-0084: User Avatar <https://xmpp.org/extensions/xep-0084.html>.

21. XEP-0153: vCard-Based Avatars <https://xmpp.org/extensions/xep-0153.html>.

22. XEP-0054: vcard-temp <https://xmpp.org/extensions/xep-0054.html>.

23. XEP-0280: Message Carbons <https://xmpp.org/extensions/xep-0280.html>.

24. XEP-0191: Blocking Command <https://xmpp.org/extensions/xep-0191.html>.

25. Support for the Entity Use Cases and Occupant Use Cases is REQUIRED; support for the remaining use cases is RECOMMENDED.

26. XEP-0045: Multi-User Chat <https://xmpp.org/extensions/xep-0045.html>.

27. Implementations should take note that future versions of these compliance suites may rely on Mediated Information eXchange (MIX) (XEP-0369) [28] instead.

28. XEP-0369: Mediated Information eXchange (MIX) <https://xmpp.org/extensions/xep-0369.html>.

29. XEP-0249: Direct MUC Invitations <https://xmpp.org/extensions/xep-0249.html>.

30. XEP-0048: Bookmark Storage <https://xmpp.org/extensions/xep-0048.html>.

31. XEP-0223: Best Practices for Persistent Storage of Private Data via Publish-Subscribe <https://xmpp.org/extensions/xep-0223.html>.

32. XEP-0049: Private XML Storage <https://xmpp.org/extensions/xep-0049.html>.

33. XEP-0198: Stream Management <https://xmpp.org/extensions/xep-0198.html>.

34. XEP-0313: Message Archive Management <https://xmpp.org/extensions/xep-0313.html>.

35. XEP-0085: Chat State Notifications <https://xmpp.org/extensions/xep-0085.html>.

36. XEP-0352: Client State Indication <https://xmpp.org/extensions/xep-0352.html>.

37. XEP-0357: Push Notifications <https://xmpp.org/extensions/xep-0357.html>.

38. The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>.

39. The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <https://xmpp.org/registrar/>.

Abstract:	This document defines XMPP protocol compliance levels.
Authors:	Sam Whited, Jonas Wielicki
Copyright:	© 1999 – 2017 XMPP Standards Foundation. SEE LEGAL NOTICES.
Status:	Proposed
Type:	Standards Track
Version:	0.4
Last Updated:	2018-01-25