XEP-0157: Contact Addresses for XMPP Services

NOTICE: This Informational specification defines a best practice or protocol profile that has been approved by the XMPP Council and/or the XSF Board of Directors. Implementations are encouraged and the best practice or protocol profile is appropriate for deployment in production systems.

Table of Contents

1. Introduction

RFC 2142 [1] specifies conventional electronic mailbox names for common services, roles, and functions related to SMTP, NNTP, and HTTP (such as hostmaster@domain.tld, usenet@domain.tld, and abuse@domain.tld). However, no such conventional email address or XMPP address has been specified for XMPP services (e.g., in RFC 3920 [2]). This document remedies that oversight, and the email recommendation specified here has been incorporated into RFC 6120 [3].

2. Email Address

Consistent with RFC 2142, a domain that offers a Jabber/XMPP service SHOULD provide an Internet mailbox of "XMPP" for inquiries related to that service.

3. XMPP Addresses

The administrators of an XMPP service may desire to advertise contact information related to that service. [4] This contact information may include email addresses, web URLs, and JabberIDs for specific roles and functions such as the service administrators, abuse reports, customer feedback, sales inquiries, technical support, and security concerns. For this purpose, domains SHOULD support the electronic mailboxes required by RFC 2142. However, additional contact mechanisms may be desirable, and it would be helpful if those who want to initiate contact could discover the contact information using standard XMPP extensions, specifically Service Discovery (XEP-0030) [6]. To make such discovery possible, we specify a Service Discovery Extensions (XEP-0128) [7] mechanism that a server SHOULD return in response to service discovery information ("disco#info") requests sent to the bare domain of the server. This information MUST be scoped using a FORM_TYPE of "http://jabber.org/network/serverinfo" (as already specified in XEP-0128) and data form fields registered for this purpose as defined in the XMPP Registrar Considerations section of this document.

To illustrate this usage, consider the following example of a disco#info request sent to the mythical shakespeare.lit XMPP server:

Example 1. Entity queries server for information

<iq from='juliet@capulet.com/chamber'
    to='shakespeare.lit'
    id='disco1'
    type='get'>
  <query xmlns='http://jabber.org/protocol/disco#info'/>
</iq>

Example 2. Server communicates information

<iq from='shakespeare.lit'
    to='juliet@capulet.com/chamber'
    id='disco1'
    type='result'>
  <query xmlns='http://jabber.org/protocol/disco#info'>
    <identity category='server' type='im'/>
    <feature var='http://jabber.org/protocol/disco'/>
    <x xmlns='jabber:x:data' type='result'>
      <field var='FORM_TYPE' type='hidden'>
        <value>http://jabber.org/network/serverinfo</value>
      </field>
      <field var='abuse-addresses'>
        <value>mailto:abuse@shakespeare.lit</value>
        <value>xmpp:abuse@shakespeare.lit</value>
      </field>
      <field var='admin-addresses'>
        <value>mailto:xmpp@shakespeare.lit</value>
        <value>xmpp:admins@shakespeare.lit</value>
      </field>
      <field var='feedback-addresses'>
        <value>http://shakespeare.lit/feedback.php</value>
        <value>mailto:feedback@shakespeare.lit</value>
        <value>xmpp:feedback@shakespeare.lit</value>
      </field>
      <field var='sales-addresses'>
        <value>xmpp:bard@shakespeare.lit</value>
      </field>
      <field var='security-addresses'>
        <value>xmpp:security@shakespeare.lit</value>
      </field>
      <field var='support-addresses'>
        <value>http://shakespeare.lit/support.php</value>
        <value>xmpp:support@shakespeare.lit</value>
      </field>
    </x>
  </query>
</iq>

4. Deployment Notes

The "domain.tld" at which the XMPP service is hosted need not be the same as the "domain.tld" at which the email service is hosted. For example, it is common for a service provider to host its XMPP service at a hostname such as "jabber.example.org" whereas email related to the service provider is sent to a hostname of "example.org". Thus while the XMPP address and email address may be the same for some service providers (e.g., both "xmpp@example.com"), that similarity is not necessary.

Although some service providers that use the same address for both XMPP and email messaging may integrate delivery of messages sent by those mechanisms (e.g., XMPP messages sent while a user is offline are redirected to email delivery), XMPP and email remain separate messaging systems.

A service provider that supports the functionality specified herein may advertise the service through a Mailto URI (see RFC 2368 [8]) of <mailto:xmpp@domain.tld> and through appropriate XMPP URIs (see RFC 5122 [9]) such as <xmpp:admins@domain.tld> or (per XMPP URI Query Components (XEP-0147) [10]) <xmpp:admins@domain.tld?message>.

It is a matter of service policy whether the XMPP addresses provided are dedicated accounts or aliases that redirect communications to the appropriate accounts.

5. Security Considerations

Providing or advertising contact addresses may open those addresses to unwanted communication. Server administrators should balance the need for openness with the desire for control over communication with customers and peers.

6. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [11].

7. XMPP Registrar Considerations

The XMPP Registrar [12] includes the following information in its registries.

<form_type>
  <name>http://jabber.org/network/serverinfo</name>
  <doc>XEP-0157</doc>
  <desc>
    Forms enabling the communication of contact addresses
    and other server information.
  </desc>
  <field
      var='abuse-addresses'
      type='list-multi'
      label='One or more addresses for communication related to abusive traffic'/>
  <field
      var='admin-addresses'
      type='list-multi'
      label='One or more addresses for communication with the service administrators'/>
  <field
      var='feedback-addresses'
      type='list-multi'
      label='One or more addresses for customer feedback'/>
  <field
      var='sales-addresses'
      type='list-multi'
      label='One or more addresses for communication related to sales and marketing'/>
  <field
      var='security-addresses'
      type='list-multi'
      label='One or more addresses for communication related to security concerns'/>
  <field
      var='support-addresses'
      type='list-multi'
      label='One or more addresses for customer support'/>
</form_type>

Appendices

Appendix A: Document Information

Series: XEP
Number: 0157
Publisher: XMPP Standards Foundation
Status: Active
Type: Informational
Version: 1.0.1
Last Updated: 2018-07-21
Approving Body: XMPP Council
Dependencies: XMPP Core, XEP-0128
Supersedes: None
Superseded By: None
Short Name: N/A
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 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.

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