XEP-0105: Tree Transfer Stream Initiation Profile

A profile describing metadata for transferring trees of files using stream inititation.
Ryan Eatmon
© 2003 – 2018 XMPP Standards Foundation. SEE LEGAL NOTICES.


WARNING: This document has been automatically Deferred after 12 months of inactivity in its previous Experimental state. Implementation of the protocol described herein is not recommended for production systems. However, exploratory implementations are encouraged to resume the standards process.
Standards Track
0.3.1 (2018-11-03)
Document Lifecycle
  1. Experimental
  2. Deferred
  3. Proposed
  4. Stable
  5. Final

1. Introduction

File transfers of entire trees require a lot more metadata and prior setup to link paths to files with unique ids so that clients can track them. This profile provides a more robust method of defining that metadata so that directory trees can be transfered.

2. Requirements

3. Usage

The tree transfer profile is in the "http://jabber.org/protocol/si/profile/tree-transfer" namespace. The profile is fairly simple: it consists of the root element with child elements that specify a directory structure of files with stream ids that will be used for each file.

This profile requires support for the File Transfer profile described in SI File Transfer (XEP-0096) [1]. Once you have accepted this SI, a new SI using the File Transfer profile will be offered for each file in the tree. This profile provides a mapping of files with paths and reserved stream ids which will be used to auto-accept a File Transfer SI that uses that same stream id from the sender.

The root element is <tree> and has two attributes. The attributes are used only during the offer stage of stream initiation:

The size and numfiles attributes MUST be present in the profile.

The only possible child element of the root is <directory/> since there are other specifications that handle single file transfers. The directory structure is sent in a hierarchical manner with nested <directory/> and/or <file/> tags. One or more <file/> elements will be sent, one for each file. One or more <directory/> elements will be sent, one for each directory.

The <directory/> element has one attribute:

The attribute is REQUIRED on each <directory/> element.

The <file/> element has two attributes:

Both attributes are REQUIRED on each <file/> element. The total number of <file> elements MUST equal the numfiles attribute sent in the <tree/> element.

The stream-method that is accepted for a Tree Profile SI MUST be remembered and the subsequent File Transfer SIs MUST NOT provide a Feature Negotiation packet. The stream-method has already been chosen and should be used for all of the streams.

Implementations of this profile MUST support Stream Initiation (XEP-0095) [2] and XEP-0096.

4. Examples

Example 1. Profile Usage in Stream Initiation Offer
<iq type='set' id='offer1' to='receiver@jabber.org/resource'>
      <directory name='cd_collection'>
        <file sid='ft1' name='coll.index'/>
        <directory name='album1'>
          <file sid='ft2' name='song1.mp3'/>
          <file sid='ft3' name='song2.mp3'/>
          <file sid='ft4' name='song3.mp3'/>
          <file sid='ft5' name='song4.mp3'/>
        <directory name='album2'>
          <file sid='ft6' name='song1.mp3'/>
          <file sid='ft7' name='song2.mp3'/>
          <file sid='ft8' name='song3.mp3'/>
          <file sid='ft9' name='song4.mp3'/>
    <feature xmlns='http://jabber.org/protocol/feature-neg'>
      <x xmlns='jabber:x:data'>
        <field var='stream-method' type='list-single'>
Example 2. Simple Profile Usage in Stream Initiation Result
<iq type='result' to='sender@jabber.org/resource' id='offer1'>
  <si xmlns='http://jabber.org/protocol/si'>
    <feature xmlns='http://jabber.org/protocol/feature-neg'>
      <x xmlns='jabber:x:data' type='submit'>
        <field var='stream-method'>
Example 3. Subsequent File Transfer Offer
<iq type='set' id='offer2' to='receiver@jabber.org/resource'>
  <si xmlns='http://jabber.org/protocol/si'
    <file xmlns='http://jabber.org/protocol/si/profile/file-transfer'
Example 4. Subsequent File Transfer Result
<iq type='result' to='sender@jabber.org/resource' id='offer2'>
  <si xmlns='http://jabber.org/protocol/si'/>

Above is repeated for ft2, ft3, etc...

5. IANA Considerations

No interaction with the Internet Assigned Numbers Authority (IANA) [3] is required as a result of this document.

6. XMPP Registrar Considerations

The profile described in this document will be registered with XMPP Registrar [4] as a valid Stream Initiation profile.

7. XML Schema

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


  <xs:element name='tree'>
      <xs:attribute name='numfiles' use='required' type='xs:integer'/>
      <xs:attribute name='size' use='required' type='xs:integer'/>
      <xs:element ref='directory' minOccurs='0' maxOccurs='1'/>

  <xs:element name='directory'>
      <xs:attribute name='name' use='required' type='xs:string'/>
      <xs:element ref='directory' minOccurs='0' maxOccurs='unbounded'/>
      <xs:element ref='file' minOccurs='0' maxOccurs='unbounded'/>

  <xs:element name='file'>
      <xs:attribute name='name' use='required' type='xs:string'/>
      <xs:attribute name='sid' use='required' type='xs:string'/>



Appendix A: Document Information

XMPP Standards Foundation
Standards Track
Last Updated
Approving Body
XMPP Council
XEP-0095, XEP-0096
Superseded By
Short Name
Source Control

This document in other formats: XML  PDF

Appendix B: Author Information

Ryan Eatmon


This XMPP Extension Protocol is copyright © 1999 – 2024 by the XMPP Standards Foundation (XSF).


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).

Visual Presentation

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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 <https://xmpp.org/community/> 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

1. XEP-0096: SI File Transfer <https://xmpp.org/extensions/xep-0096.html>.

2. XEP-0095: Stream Initiation <https://xmpp.org/extensions/xep-0095.html>.

3. 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/>.

4. 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/>.

Appendix H: Revision History

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

  1. Version 0.3.1 (2018-11-03)
    Fix a bunch of typos, batch-style.
  2. Version 0.3 (2003-09-22)
    Updated directory structure from flat to hierarchical.
  3. Version 0.2 (2003-07-23)
    Fixed bad data types in the schema.
  4. Version 0.1 (2003-07-09)
    Initial version.

Appendix I: Bib(La)TeX Entry

  title = {Tree Transfer Stream Initiation Profile},
  author = {Eatmon, Ryan},
  type = {XEP},
  number = {0105},
  version = {0.3.1},
  institution = {XMPP Standards Foundation},
  url = {https://xmpp.org/extensions/xep-0105.html},
  date = {2003-07-09/2018-11-03},