Charter of the Efficient XML Interchange Working Group

The Efficient XML Interchange Working Group is part of the W3C XML Activity and follows the Working Group process described in section 6.2 Working Groups and Interest Groups of the W3C Process Document.

Table of Contents

  1. Mission
  2. Scope and Goals
  3. Out of scope
  4. Success criteria
  5. Deliverables and duration
  6. Expected milestones
  7. Coordination with Other Groups
  8. Working Group participation
  9. Meetings
  10. Communication
  11. Confidentiality
  12. Patent Policy
  13. About this Charter


The main objective of the Efficient XML Interchange (EXI) Working Group is to develop a format that allows efficient interchange of the XML Information Set, based on the conclusions of the XML Binary Characterization Working Group.

Scope and Goals

During this Charter period the Working Group will focus on publishing a strict profile of the EXI 1.0 format for memory-constrained devices, especially devices with little or no run-time memory allocation, and on canonicalization as it pertains to the EXI format.

The Working Group may also work on gathering requirements for future work. Future work might for example include a new revision of the EXI format, to account for XML Schema 1.1 and also the XPath and XQuery Data Model (XDM), as well as working with the SVG Working Group to achieve increased benefits for that format, and perhaps also for HTML 5.

Out of scope

This Working Group is not chartered to:

  1. Introduce a new data model for XML;
  2. Develop an application-specific format. Like XML itself, the new format must support a wide variety of applications.

Success criteria

A Recommendation for the EXI Profile is to be produced.

A Recommendation for EXI Canonicalization is to be produced.

A second edition of EXI 1.0 may also be produced, if and as needed.

Deliverables and duration


The Working Group is expected to produce:


The expiration date of this charter is 31 May 2015.


Specification FPWD LC CR PR Rec
Note: The group will document significant changes from this initial schedule on the group home page.
EXI Profile N/A [July 2012] [May 2013] July 2013 October 2013
EXI Canonicalization November 2013 March 2014 July 2014 November 2014 January 2015

Timeline View Summary

February 2013
Candidate Recommendation, EXI Profile for low-resource devices
June 2013
Proposed Recommendation, EXI Profile for low-resource devices
September 2013
Recommendation, EXI Profile for low-resource devices
November 2013
FPWD of Canonicalization
March 2014
LC of Canonicalization
July 2014
CR of Canonicalization
November 2014
PR of Canonicalization
January 2015
Recommendation of Canonicalization

Coordination with Other Groups

W3C Groups

The Working Group should coordinate its efforts with W3C Working Groups, in particular in the XML Activity as well as the Technical Architecture Group.

External Groups

Open Mobile Alliance (OMA) develops standards for mobile device industry. Specifications such as OMA Device Management use XML and are designed with sensitivity to implementation foot-print and communication bandwidth.
The Web3D Consortium continues to participate in the EXI working group. Web3D intends to upgrade the Extensible 3D (X3D) Graphics Specification Compressed Binary Encoding (CBE) from utilizing Fast Infoset (FI) to EXI, once EXI becomes a W3C Recommendation.
ZigBee Smart Energy
Smart Energy 2 uses EXI with a schema-informed grammar as an alternative to plain text XML message (as of 0.9 draft).

Working Group participation

Effective participation is expected to consume one workday per week for each Working Group participant; two days per week for editors. The Chair shall ensure that the criteria for Good Standing are understood and followed.


The chair of this Working Group is Takuki Kamiya (Fujitsu).

W3C Team resources

The initial W3C Team contacts are Carine Bournez and Liam Quin. It is expected that this Working Group will consume up to 0.25 FTE, including administrative logistics.


The Working Group will have distributed meetings, one to two hours every week, and one or two face–to–face meetings each year.


The Working Group will utilize a W3C Member mailing list, member-exi-wg@w3.org.


The proceedings of this Working Group are Member-only, subject to exceptions made by the Chair, after consultation with the Working Group.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty–Free basis.

About this Charter

This charter for the EXI Working Group has been created according to section 6.2 of the Process Document. In the event of a conflict between the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Please also see the previous charter for this group.

Liam Quin, XML Activity Lead and Team Contact