R&D Information

Secure and Reliable Sharing of User Attributes
among Websites—Information Sharing Control
Technology Enabled by the Latest Liberty Alliance
Specifications

NTT has developed a new system for secure andreliable sharing of user-attributes among websites,
providing a new information-sharing platform forInternet services. The two main features of the system
are as follows.
1. The system is one of the world’s first applications of the Phase 2 Specifications of the Liberty Alliance Project*1. The Liberty Alliance isdeveloping open standards for federated*2 network-identity management and identity-basedservices.
2. The end-user has flexible control of the conditions for sharing user-attributes among websites. This prevents the leakage of private information against the user’s wishes.
The system provides a platform for creating new
business models for the Internet and should findapplication in various fields.
Background
Internet services such as online shopping are now
providing more personalized services through user
authentication and utilization of user-attributes suchas names or addresses. Sharing user-attributes among
websites is an effective tool in providing personalizedservices; it requires both interoperable standards andsecurity for private information. For this purpose,*1 Liberty Alliance Project (http://www.projectliberty.org/) wasformed in September 2001 to serve as the premier open-standards
organization for federated identity and identity-based services.
The Alliance is delivering specifications and guidelines for a complete network identity infrastructure that will resolve many of thetechnological and commercial issues hindering the deployment ofidentity-based web services. Alliance members include major service providers, vendors, and carriers from North America, Europe,and Japan.
*2 Federation refers to an association of some set of service providers
and identification providers. Federating means the binding ofproviders as network entities.

106

NTT has implemented the latest open standards fromthe Liberty Alliance Project (Phase 2 Specifications)along with a sharing-policy control mechanism
developed in house, to provide improved privacy protection in the sharing of user information among websites.
The Phase 1 Liberty Alliance Specifications are for
the Identity Federation Framework, which enables“simplified sign-on”. With Liberty-enabled simplified sign on, users are given access to websites in a“circle of trust” after a single successful authentication of the user at the first site. This frees users fromhaving to enter passwords every time they accesssecure websites. More than 20 products and services
enabled by the Liberty Alliance Phase 1 Specifications are now on the market.
The Phase 2 Specifications define an Identity Web
Services Framework, which enables the sharing ofuser-attributes between federated websites based on
per-user-defined permission. NTT’s system is one of
the first in the world to utilize the Phase 2 Specifications.
Technical points
In addition to the single-sign-on user authentication
and user-attribute sharing among websites defined by
the Liberty Alliance, NTT provides a new method for
securely sharing user-attributes in which end-users
can configure the sharing policy for their own private
information. For example, users might want to provide only their names to music sites but they must
give out addresses to online shopping sites in order toreceive delivery. Below is an outline of the system’s
main features.
1. Sharing of user attributes among federated entities on the Internet.
The Phase 2 Specifications from the Liberty
Alliance describe the sharing of user attributes by
NTT Technical ReviewR&D Information

multiple organizations that hold the attributes.
This is achieved through Internet Web-sites that
represent the organizations, and frees users fromtyping attributes such as their names, addresses,
and telephone numbers every time they accesssecure websites. NTT’s system can handle Japanese-language data for Japanese web-sites.
2. Privacy Protection
The Phase 2 Specifications describe the sharingof user-attributes according to user-defined permission. Moreover, NTT’s new informationresource-sharing method improves privacy protection by ensuring that only the minimum essential information is shared among the organizations.

Future plans
NTT will contribute to further development of theinformation society by developing techniques for
integrating various network services, providing customers with convenient one-stop services. The Phase
3 and later specifications will be aimed more towards
service concepts. They will define methods for sharing extended attributes such as users’ presence information. This will enable the provision of morestrongly individualized services. NTT will continue
to contribute as a member of the Liberty Alliance andwill energetically promote these specifications inJapan.
For further information, please contact
NTT Information Sharing Platform Laboratories
Musashino-shi, 180-8585 Japan
E-mail: koho@mail.rdc.ntt.co.jp

Vol. 2 No. 1 Jan. 2004

107