Global Standardization Activities

Standardization Activities of the Liberty
Alliance
Teruko Miyata†
Abstract
This article provides an overview of the Liberty Alliance, which was established to create open global standards for federated identity management technology and related business guidelines, and surveys
its activities, achievements, and current progress.

1. Introduction
The Liberty Alliance Project (“Liberty Alliance”)
was founded in 2002 to establish open, international
standards-based specifications for federated identity
management technology and related business guidelines [1]. This international standardization organization currently has over 150 participating companies
and organizations from around the world. This article
provides an update to the April 2003 article in NTT
Technical Review [2].
2. Federated identity management technology
Federated identity management technology refers
to technology for managing several identities andlinking them to their various Web sites in a safe andsecure way. It relieves the rise in the number ofaccounts that an individual must manage as the number of Web services grows. Here, identity refers generally to any information that identifies an individual,such as user account information for a system. To
implement federated identity management, the concepts of an Identity Provider (IdP), a service provider(SP), and a federated ID [3] are introduced. IdP is astructure that provides unified management ofauthentication information. SP is a web site that provides a service, such as an e-commerce site. The concept of a federated ID refers to how a relationship iscreated between the IdP ID and the ID managed by† NTT Information Sharing Platform Laboratories
Musashino-shi, 180-8585 Japan
E-mail: lap@lab.ntt.co.jp

Vol. 4 No. 5 May 2006

the SP by generating a random string called a pseudonym.
3. Liberty Alliance standardization activities
To establish these international technical standards
for federated ID management, the Liberty Alliance isreleasing them in four major phases (Fig. 1). Phase 1
covered “single sign-on” (SSO), Phase 2 extended
the SSO standard in Phase 1 and transformed it so it
was based on user-authorized attributes. In Phase 3,
ID-FF was adopted by OASIS (Organization for theAdvancement of Structure Information Standards)
for SAML v2.0 (security assertion markup language
v2.0), extending the attribute-exchange functions andspecifications for linking to various types of Web services. Phase 1 and 2 specifications have been completed [4], and preparation for freezing the final specifications for Phase 3 is proceeding. Below, this article gives an overview of the architecture that the Liberty Alliance has settled on (“Liberty Architecture”)
and reports the current progress of Phase 3. It also
introduces a particular Web service example for theregular exchange of personal information in digital
broadcasting. Finally, it discusses future activities interms of NTT’s strategy and Phase 4.
4. Overview of Liberty Architecture
The Liberty Architecture is composed of threemain components and is based on SAML and SOAP(simple object access protocol) (Fig. 2).
• Identity Federation Framework (ID-FF): Specifications for the most basic set of functions required51

Global Standardization Activities

2003

2002
Phase 1• Single sign on(ID-FF)– 2002/07 v1.0
– 2003/01 v1.1

2004

2005

Phase 22006

Phase 3Phase 4• ID-FF adopted by OASIS for SAMLv2.0– 2005/03 SAMLv2.0• Extended attribute exchange (ID-WSF)– 2005/04 v1.1
– 2006/03 v2.0
• Service type specifications– Interface specifications for presence
and geo-location Web services– 2006/03 draft v1.0 (scheduled forpublic release)• Issue of reference documents forcomplying with Japanese personal
information protection laws
– 2005/03• Extended single sign on(ID-FF)– 2003/11 v1.2
• Attribute exchange(ID-WSF)– 2003/11 v1.0

• Strong authentication(ID-SAFE)– Simple and secure nonpassword authentication
methods– Interoperability between
authentication devices andservices– 2006Q4 (scheduled topublic release)

Personal Employee Presence Contact

OASIS SAML v2.0
SSO internationalstandards

Geo-location
profileContact
profilePresence
profileEnables interoperable identity services such as
personal identity profile service, employee service,presence service, and geo-location service
EmployeeprofileEnables identity
federation andmanagement throughfeatures such as identity/
account linkage,
simplified sign on, andsimple session
management

Liberty Identity Services Interface
Specifications (ID-SIS)

Personal
profileLiberty Identity
Federation Framework(ID-FF)

Geo-loc

Demographic
profilePreference
profileUsagehistory

Fig. 1. Liberty Alliance specification phases.

TVA Phase 1
TVA Phase 2SP006-3
Exchange ofpersonal
profileLiberty Identity Web Services Framework(ID-WSF)
Provides the framework for building interoperable identity
services, permission-based attribute sharing, identity
service description and discovery, and the associatedsecurity profiles

Liberty specifications build on existing standards(SAML, SOAP, WS-Security, XML, etc.)

Fig. 2. Position of Liberty architecture and TVA specifications.

for implementing SSO, such as ID federation. ID
federation, SSO, and single log-out were finalizedin Ver. 1.1. Ver. 1.2 enabled links between IdPs aswell as IdP anonymous authentication.
• Identity Web Service Framework (ID-WSF): Setof specifications for exchanging user attributeswith sites providing Web services. Personal information is shared with the service site based on per52

mission from the user. Identity services can also be
discovered and used.
• Identity Service Interface Specifications (IDSIS): Set of specifications for the actual service
interface for implementing Web services based onID-WSF. It prescribes specifications for providing
personal information or employee information (inthe case of a corporate service) as a Web Service
NTT Technical Review

Global Standardization Activities

based on an actual identity. In particular, the dataservice template (DST) interface of ID-WSF isessential in ID-SIS. ID-SIS can be standardized foreach service. At the Liberty Alliance, model DST
specifications for handling various services havebeen provided within the ID-WSF specification set.
Attribute information can be exchanged based on
the ID-WSF framework by using a DST to create a
new service interface.

Alliance ID-WSF v1.0 specification set, standardizing the exchange of viewer attributes. Furthermore,ETSI has decided on this viewer attribute exchange
specification (TVA Phase 2 SP006-3) as an ETSI
standard (ETSI TS 102 822-6-3, released Jan. 2006)[8]. In practical terms, the three profiles already specified by TVA (viewing usage profile, viewing preference profile, and demographic data profile) will be
managed and shared using the Liberty Alliance IDWSF v1.0 scheme.

5. Phase 3 (2004–2005)
7. Future activities
Liberty Alliance activities from 2004 to 2005 werecalled Phase 3. The main objectives for the technicalspecifications of each component were achieved. Theuse of the Liberty Alliance ID-FF specification set for
SSO in OASIS SAML v2.0 technology is expected toboost efforts to make SSO an international standard
and also to gain wider adoption. In the ID-WSF specification set, new specifications regulating personal
data management were added for social network services. In the ID-SIS specification set, three new Web
service interface specifications were published (forpresence, geo-location, and contact-book services),
adding to the existing personal data and employee
data specifications. Finally, in response to the enactment of the new personal information protection law
in Japan, which took effect in April 2005, “LibertyAlliance and Japan’s Personal Information ProtectionAct” [5] was released.
6. Adoption of Liberty ID-WSF as a personal
information exchange specification fordigital broadcasting
The Liberty Alliance is conducting liaison activities, collaborating with standardization associations
in each industry, and supporting the adoption of Liberty specifications. In 2004, it made a liaison agreement with the TV-Anytime Forum (TVA) [6], [7].
Most members of TVA are European broadcasters
and vendors, and TVA is creating international standards for new broadcast services incorporating links
to telecommunications and local storage of broadcasts. Standards adopted by TVA have already beenreferenced by the European Telecommunications
Standards Institute (ETSI) and by the Association ofRadio Industries and Businesses (ARIB). NTT is participating in both the Liberty Alliance and TVA and isestablishing itself in a leadership position in technicaland business areas in both associations. Through thisliaison agreement, TVA has adopted the Liberty
Vol. 4 No. 5 May 2006

In the final Phase 4, the Liberty Alliance will establish a group to investigate strong authentication
methods against “phishing” and ID theft and will
push forward work on interoperability between
authentication devices and services. NTT will continue to take part in Liberty Alliance standardizationactivities.
References
[1]
[2]

[3]

[4]
[5]

[6]
[7]
[8]

Liberty Alliance: http://www.projectliberty.org/K. Terada and K. Takahashi, “Activities Targeting the Standardization of the Liberty Alliance,” NTT Technical Review, Vol. 1, No. 1,
pp. 94-96, 2003.
Y. Koga, T. Miyada, and K. Takahashi, “Trends in Management of
Personal Information and ‘Liberty Alliance’, the Association forStandardization of Information Sharing,” Journal of the Institute ofElectronics Information and Communication Engineers, Vol. 87, No.
6, pp. 504-507 (in Japanese).
Liberty Alliance Specifications: http://www.projectliberty.org/specs/“Liberty Alliance and Japan’s Personal Information Protection Act,”
http://www.projectliberty.org/jp/resources/lib-JapanPIPAct-ja.pdf(in Japanese).
TV-Anytime Forum: http://www.tv-anytime.org
M. Kawamori, “Recent Activities of the TV-Anytime Forum,” NTT
Technical Review, Vol. 4, No. 3, pp. 77-80, 2006.
http://webapp.etsi.org/exchangefolder/ts_1028220603v010101p.pdf

Teruko Miyata
Senior Research Engineer, NTT Information
Sharing Platform Laboratories.
She received the B.S. and M.S. degrees inmathematical science from Ochanomizu University, Tokyo, in 1991 and 1993, respectively. She
joined NTT Laboratories in 1993. Her current
field of interest is identity management businessand technology.

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