ODRL Creative Commons Profile

Working Draft: 28 January 2005

This version:
http://odrl.net/Profiles/CC/WD-20050128.html
Latest version:
http://odrl.net/Profiles/CC/WD.html
Previous version:
http://odrl.net/Profiles/CC/WD-20041130.html
Editor(s):
Renato Iannella, ODRL Initiative, renatoodrl.net

Abstract

This Working Draft describes the semantics of the Creative Commons licenses and how they can be represented using a Profile of the ODRL rights expression language.

Status of this document

This is a public Working Draft of the ODRL Creative Commons Profile document. It has been produced by the ODRL Creative Commons Profile Working Group. Comments on this document should be sent to the editors and discussion of this document takes place on the working group mailing list.

Publication as a Working Draft does not imply endorsement by the ODRL Initiative. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This is a Last Call Working Draft for review by WG Members and other interested parties. If no substantive issues are found then the Working Group plans to submit it for consideration as a Draft Specification as per the WG Process and Procedures. Comments can be sent until 11 February 2005.

Table of contents

1 Overview
2 Creative Commons Licenses
3 Mapping to ODRL
4 Example Scenarios
Appendix A: Data Dictionary
Appendix B: XML Schemas
Appendix C: CC License Mapping
References
Change History

1 Overview

The Creative Commons [CC] project has created a number of licenses and semantics for describing usage rights over content. The CC licenses are primarily intended to convey the semantics to the end user of the content. The ODRL is an advanced rights expression language (REL) [ODRL]. The objective of this document is to outline a Profile of the ODRL REL that incorporates the semantics and licenses from CC. This will then enable those who require more advanced REL mechanisms to utilise both the CC license semantics and the ODRL REL features.

The requirements of this Profile are to:

2 Creative Commons Licenses

The CC Licenses are described by three major characteristics:

Each of these three characteristics contain specific values representing different Permissions, Prohibitions, and Requirements. Each also has a unique URI.

For example, the Permissions include the following: And the Prohibitions includes: And the Requirements includes:

The complete list of all CC license characteristics can be found in Appendix A.

There are a number of formal licenses defined by CC in version 2.0. These include various combinations of the above license characteristics. The primary licenses, including their unique URIs, include:

Appendix C defines all the current CC Licenses in terms of the new XML elements required to express the same semantics using the ODRL/CC Profile.

The purpose of this Profile is not to replace the standard CC licenses, but to allow additional semantics to be expressed in separate ODRL offers or agreements.

3 Mapping to ODRL

The CC Permissions and Requirements map directly to ODRL Permissions and Requirements. ODRL already covers the semantics of CC Attribution and the others are defined in the Profile Data Dictionary (See Appendix A) and extension XML schema (See Appendix B).

CC defines two Permissions that all licenses include:

More specifically [CC-Full] CC Reproduction includes the right: These allow the typical private end-use rights, which ODRL makes more explicit in its Play, Display, Execute, and Print Permissions.

The CC Distribution [CC-Full] includes the right:

Both Reproduction and Distribution are examples of new semantics that are captured in the ODRL/CC Profile (see Appendix A and B).

Given that there is an overlap in semantics of the new CC terms and the existing ODRL terms, new ODRL expressions will need to ensure that the final semantics are clear and unambiguous. For example, since the CC Reproduction right is a superset of the ODRL Print right, any expression including CC Reproduction and ODRL Print will be expressing the same rights. However, there maybe an issue if the Print included a Constraint, as then the two Permissions are in conflict. There is no general technical solution to this as the semantics involved are overlapping so care must be undertaken when creating such expressions.

However, in the cases were the rights holder does wish to be more specific with the CC Reproduction right, then the expression should not include the CC Reproduction right but only the more specific ODRL Permissions and Constraints. For example, the rights holder may only wish that their work be displayed (publicly and privately) and printed once (privately). In this case the expression would include the ODRL display and print with a Constraint, and the CC Distribution elements.

The current ODRL 1.1 model does not support the concept of CC Prohibitions. This is because the behavior of the ODRL model is that if a right (permission) does not explicitly appear in the expression then it is not allowed. Hence, in an ODRL expression, if Commercial Use was prohibited, then it would simply not be mentioned in the XML code. Conversely, if Commercial Use was explicitly allowed (such as the ODRL Sell permission), then it would appear in the XML code.

There are two ways in which the CC Commercial Use semantics can be represented in ODRL. The first way would be to define Commercial Use in the negative and to make this an ODRL Constraint. The second way would be to utilise the existing ODRL Purpose constraint and define a URI for non-Commercial use. For the purposes of this Profile, it would be more flexible and consistent to define a new NonCommercialUse Constraint in ODRL.

It would also be useful to add links from the ODRL expression to one of the standard CC Licenses. This will allow access to the human-readable versions of the CC semantics, as well as link the two machine expressions. The context of the entire ODRL expression can be used to indicate this reference link. Note, however, that referencing the CC License URI is an informative link - the ODRL expression is normative. In addition it is not recommended that a link to the CC license be used when the overall ODRL expression narrows (or restricts) the rights more than the original CC license.

4 Example Scenarios

Consider the scenario described on the CC website about Anita and her song Volcano Love. Anita chooses the Attribution-NonCommercial-ShareAlike CC license. We can now express that using the ODRL CC Profile, and include additional information about Anita (as the rights holder), and direct links to the content (asset).

<?xml version="1.0" encoding="UTF-8"?>
<o-ex:rights xmlns:o-ex="1.1/ODRL-EX"
  xmlns:o-dd="1.1/ODRL-DD"
  xmlns:cc="CC-20">
  <o-ex:offer>
     <o-ex:context>
        <o-dd:reference>http://creativecommons.org/licenses/by-nc-sa/2.0/
        </o-dd:reference>
      </o-ex:context>
    <o-ex:asset>
      <o-ex:context>
        <o-dd:uid>urn:anita-music:songs:volcanoLove.mp3</o-dd:uid>
      </o-ex:context>
    </o-ex:asset>
    <o-ex:permission>
      <cc:Reproduction/>
      <cc:Distribution/>
      <cc:DerivativeWorks/>
    </o-ex:permission>
    <o-ex:constraint>
      <cc:NonCommercialUse/>
    </o-ex:constraint>
    <o-ex:requirement>
      <o-dd:attribution/>
      <cc:Notice/>
      <cc:ShareAlike/>
    </o-ex:requirement>
    <o-ex:party>
      <o-ex:context>
        <o-dd:uid>urn:music-people:id-anita-001</o-dd:uid>
        <o-dd:name>Anita Music</o-dd:name>
        <o-dd:dLocation>anita@anita-music.biz</o-dd:dLocation>
      </o-ex:context>
      <o-ex:rightsholder/> 
    </o-ex:party>     
  </o-ex:offer>
</o-ex:rights> 

Extending the above example, lets say that Anita wants to make two additions. Firstly she wants to limit the Distribution permission to the USA only. Secondly, she wants to make clear the exact text that should be used for the Attribution requirement. In this case, the above example would be modified with the following two updated elements.

      <cc:Distribution>
        <o-ex:constraint>
          <o-dd:spatial>
            <o-ex:context>
              <o-dd:uid> urn:iso3166:US </o-dd:uid>
            </o-ex:context>
          </o-dd:spatial>     
        </o-ex:constraint>
      </cc:Distribution>

      <o-dd:attribution>
        <o-ex:context>
          <o-dd:remark>
              This work created by Anita Music with lyrics by
              Mary Music and sound by Jacky Music. 
          </o-dd:remark>
        </o-ex:context>
      </o-dd:attribution>

Since the above Distribution permission is narrower than the original CC license, Anita removes the link from the reference element to the original CC license.

Next, Anita wishes to make the lyrics to her song available. Anita chooses the Attribution-NonCommercial-NoDerivs CC license as this is the closest. However, she decides that she only wants the public to print her lyrics no more than once, so she includes the Display and Print permission with a Count constraint. She does not include the Reproduction permission and does not include a Reference to the CC License (as the semantics are not the same).

<?xml version="1.0" encoding="UTF-8"?>
<o-ex:rights xmlns:o-ex="1.1/ODRL-EX"
  xmlns:o-dd="1.1/ODRL-DD"
  xmlns:cc="CC-20">
  <o-ex:offer>
    <o-ex:asset>
      <o-ex:context>
        <o-dd:uid>urn:anita-music:lyrics:volcanoLove.pdf</o-dd:uid>
      </o-ex:context>
    </o-ex:asset>
    <o-ex:permission>
      <o-dd:display/>
      <o-dd:print>
        <o-ex:constraint>
          <o-dd:count>1</o-dd:count>     
        </o-ex:constraint>
      </o-dd:print>
      <cc:Distribution/>
    </o-ex:permission>
    <o-ex:constraint>
      <cc:NonCommercialUse/>
    </o-ex:constraint>
    <o-ex:requirement>
      <o-dd:attribution/>
      <cc:Notice/>
    </o-ex:requirement>
    <o-ex:party>
      <o-ex:context>
        <o-dd:uid>urn:music-people:id-anita-001</o-dd:uid>
      </o-ex:context>
      <o-ex:rightsholder/> 
    </o-ex:party>     
  </o-ex:offer>
</o-ex:rights> 

Appendix A: ODRL/CC Profile Data Dictionary (Normative)

The Creative Commons Profile data dictionary definitions:

Type Identifier Definition
Permission Reproduction The work may be reproduced
Permission Distribution The work (and, if authorized, derivative works) may be distributed, publicly displayed, and publicly performed
Permission DerivativeWorks Derivative works may be created and reproduced
Permission Sharing Noncommercial copying and distribution (like file-sharing) of the entire work are allowed
Constraint NonCommercialUse Rights may NOT be exercised for commercial purposes
Constraint NonHighIncomeNationUse Rights may NOT be exercised in nations defined as high-income enconomies by the World Bank
Requirement Notice Copyright and license notices must be kept intact
Requirement ShareAlike Derivative works must be licensed under the same terms as the original work
Requirement SourceCode Source code (the preferred form for making modifications) must be provided for all derivative works

Note: The Constraint type maps to the CC Prohibits characteristic.

Appendix B: ODRL/CC Profile XML Schema (Normative)

The Creative Commons Profile data dictionary XML Schema:

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema targetNamespace="CC-20"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:o-ex="1.1/ODRL-EX" 
    xmlns:cc="CC-20"
    elementFormDefault="qualified" attributeFormDefault="qualified">
    <xsd:import namespace="1.1/ODRL-EX" 
                 schemaLocation="1.1/ODRL-EX-11.xsd"/>
    <xsd:element name="Reproduction" type="o-ex:permissionType" 
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="Distribution" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="DerivativeWorks" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="Sharing" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="NonCommercialUse" type="o-ex:constraintType" 
                 substitutionGroup="o-ex:constraintElement"/>
    <xsd:element name="NonHighIncomeNationUse" type="o-ex:constraintType" 
                 substitutionGroup="o-ex:constraintElement"/>
    <xsd:element name="Notice" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
    <xsd:element name="ShareAlike" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
    <xsd:element name="SourceCode" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
</xsd:schema>

The file location of this XML Schema is:

  http://odrl.net/Profiles/CC/CC-20.xsd

Appendix C: CC License Mapping (Normative)

The Creative Commons License definitions and corresponding XML elements required to express the license:

CC License Name
URI
Permission Constraint Requirement
Attribution
http://creativecommons.org/
licenses/by/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
  <cc:Notice>
<o-dd:attribution>
Attribution-NoDerivs
http://creativecommons.org/
licenses/by-nd/2.0/
<cc:Reproduction>
<cc:Distribution>
  <cc:Notice>
<o-dd:attribution>
Attribution-NonCommercial-NoDerivs
http://creativecommons.org/
licenses/by-nc-nd/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:NonCommercialUse> <cc:Notice>
<o-dd:attribution>
Attribution-NonCommercial
http://creativecommons.org/
licenses/by-nc/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
<cc:NonCommercialUse> <cc:Notice>
<o-dd:attribution>
Attribution-NonCommercial-ShareAlike
http://creativecommons.org/
licenses/by-nc-sa/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
<cc:NonCommercialUse> <cc:Notice>
<o-dd:attribution>
<cc:ShareAlike>
Attribution-ShareAlike
http://creativecommons.org/
licenses/by-sa/2.0/
<cc:Reproduction>
<cc:Distribution>
  <cc:Notice>
<o-dd:attribution>
<cc:ShareAlike>
Music Sharing License
http://creativecommons.org/
licenses/by-nc-nd/2.0/deed-music
<cc:Reproduction>
<cc:Distribution>
<cc:NonCommercialUse> <cc:Notice>
<o-dd:attribution>
Sampling
http://creativecommons.org/
licenses/sampling/1.0/
<cc:Reproduction>
<cc:DerivativeWorks>
  <cc:Notice>
<o-dd:attribution>
Sampling Plus
http://creativecommons.org/
licenses/sampling+/1.0/
<cc:Reproduction>
<cc:Sharing>
<cc:DerivativeWorks>
  <cc:Notice>
<o-dd:attribution>
Noncommercial Sampling Plus
http://creativecommons.org/
licenses/nc-sampling+/1.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
<cc:NonCommercialUse> <cc:Notice>
<o-dd:attribution>
Developing Nations
http://creativecommons.org/
licenses/devnations/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
<cc:NonHighIncomeNationUse> <cc:Notice>
<o-dd:attribution>
GNU GPL
http://creativecommons.org/
licenses/GPL/2.0/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
  <cc:Notice>
<cc:ShareAlike> <cc:SourceCode>
GNU LGPL
http://creativecommons.org/
licenses/LGPL/2.1/
<cc:Reproduction>
<cc:Distribution>
<cc:DerivativeWorks>
  <cc:Notice>
<cc:ShareAlike> <cc:SourceCode>

Note: The above elements would use the appropriate XML Namespace prefix.

References

[CC] Creative Commons Project <http://creativecommons.org/>

[CC-Full] Creative Commons - Baseline rights and restrictions in all licenses <http://creativecommons.org/learn/licenses/fullrights>

[ODRL] Open Digital Rights Language (ODRL), Version 1.1. <http://odrl.net/1.1/ODRL-11.pdf> Technical Specification, ODRL Initiative, August 2002

Change History

Section Description
2 Slight editing of text for clarity
3 Added recommendation not to link to CC license if semantics are narrowed
4 Updated examples
Appendix A Added new elements (Sharing, NonHighIncomeNationUse)
Appendix B Updated XML Schema
Appendix C Added all known CC licenses