JEP-xxxx: Metacontact Storage

This document specifies a protocol for the storage of metacontacts associated with a Jabber/XMPP account.

WARNING: This document has not yet been accepted for consideration or approved in any official manner by the Jabber Software Foundation, and this document must not be referred to as a Jabber Enhancement Proposal (JEP). If this document is accepted as a JEP by the Jabber Council, it will be published at <> and announced on the <> mailing list.

JEP Information

Status: ProtoJEP
Type: Historical
Number: xxxx
Version: 0.0.1
Last Updated: 2006-02-11
JIG: Standards JIG
Approving Body: Jabber Council
Dependencies: XMPP Core, JEP-0049
Supersedes: None
Superseded By: None
Short Name: Not yet assigned

Author Information

Yann Le Boulanger


Legal Notice

This Jabber Enhancement Proposal is copyright 1999 - 2006 by the Jabber Software Foundation (JSF) and is in full conformance with the JSF's Intellectual Property Rights Policy <>. This material may be distributed only subject to the terms and conditions set forth in the Creative Commons Attribution License (<>).

Discussion Venue

The preferred venue for discussion of this document is the Standards-JIG discussion list: <>.

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 Jabber Software 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 JEP 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.

Conformance Terms

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

Table of Contents

1. Introduction
2. The storage:metacontacts Namespace
3. Security Considerations
4. IANA Considerations
5. Jabber Registrar Considerations
6. XML Schema
Revision History

1. Introduction

Sometimes, the same contact can be more than once in the roster and this just takes space. This can be the case if the user uses multiple accounts and/or has the same contact in the roster as Jabber contact and/or as other IM networks via transports. Metacontacts is a way to hide children contacts under a parent contact. Some Jabber client already implement this feature; this JEP defines a way to store thiat information on the user's Jabber server.

Private XML Storage [1] provides with a convenient method for storing user data on the server using jabber:iq:private; all we need to do is define a namespace and schema for storing this sort of information. To this end, we introduce the 'storage' element, and the 'storage:metacontacts' to handle this data.

2. The storage:metacontacts Namespace

A storage element marked by the storage:contacts namespace will contain a collection of child elements, each representing a parent metacontact with his children contacts to be displayed in the client. Only one sub-element is defined: 'parent'.

All 'parent' elements under storage MUST have a 'jid' attribute, which is the jid of the parent contact.

The parent element SHOULD contain one or more 'child' sub-element. These child elements MUST have a 'jid' attribute, which is the jid of the sub-contact. They can also have an OPTIONAL 'account' attribute that defines the account to which jid belongs (this is useful for multi-account-capable clients that also support account merging). This account attribute SHOULD be taken into account by the client only if it supports account merging and this feature is active. If no account attribute is given, the client MUST consider that child contact is in the same account as parent contact.

Example 1. An example of the parent element

<iq type='result' id='1'>
  <query xmlns='jabber:iq:private'>
    <storage xmlns='storage:metacontacts'>
      <parent jid='parent@server.tld'>
        <child jid='child1@server.tld'/>
        <child jid='child2@server.tld' account='account2@server2.tld'/>

The "child1@server.tld" address from the same account and the "child2@server.tld" address from the "account2@server2.tld" account SHOULD be displayed under the "parent@server.tld" contact.

3. Security Considerations

Security considerations related to private XML storage are described in JEP-0049.

4. IANA Considerations

This JEP requires no interaction with the Internet Assigned Numbers Authority (IANA) [2].

5. Jabber Registrar Considerations

No namespaces or parameters need to be registered with the Jabber Registrar [3] as a result of this JEP.

6. XML Schema

<?xml version='1.0' encoding='UTF-8'?>


  <xs:element name='storage'>
        <xs:element ref='parent'/>

  <xs:element name='parent'>
        <xs:element name='child' minOccurs='0'>
          <xs:attribute name='jid' type='xs:string' use='required'/>
          <xs:attribute name='account' type='xs:string' use='optional'/>
      <xs:attribute name='jid' type='xs:string' use='required'/>



1. JEP-0049: Private XML Storage <>.

2. 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 <>.

3. The Jabber Registrar maintains a list of reserved Jabber protocol namespaces as well as registries of parameters used in the context of protocols approved by the Jabber Software Foundation. For further information, see <>.

Revision History

Version 0.0.1 (2006-02-11)

First draft. (ylb)