In the pursuit of functional distributed directory services, OASIS Wednesday said it is working to
establish a better identification scheme that can be used across
domains, applications and transport protocols.
To complete this task, the OASIS Extensible Resource Identifier (XRI)
Technical Committee will define a Uniform Resource Identifer (URI), more commonly known as a URL, scheme and a corresponding Uniform Resource (URN) namespace, as well as basic
mechanisms for resolving XRIs and exchanging data and metadata associated
with XRI resources. Advanced Micro Devices, DataPower, EDS, Novell, Neustar,
NRI Pacific, OneName, Visa International and other individuals are
spearheading this task.
A fully federated XRI will address the problem of how to identify the same
logical resource stored in different physical locations. URIs uniquely
identify system resources as specifically attached to a system, such as a
Web Server or FTP server. XRI will allow for identifiers to be gauged by
both human and computers, and will provide for internationalization in the
same manner as XML.
Bill Washburn, president and managing director of the XNS Public Trust
Organization (XNSORG), which intends to contribute the Extensible Name
Service (XNS) specifications to seed the work of the OASIS committee,
explained the need for XRI definition.
“URIs are one of the three pillars of Web architecture, but most URI schemes
were developed before the era of XML and Web services,” Washburn said.
XRI examined
Jason Bloomberg, analyst for XML and Web services research firm ZapThink, told internetnews.com: “You can think of XRI as a system that provides ‘URLs for everything’ — data, systems, organizations, services, and people. Currently, we don’t
have a single, application and protocol-neutral way for identifying
these types of resources. What we do have are standards like LDAP, but
the XRI initiative goes one big step further and unifies the URL
namespaces we know and love from the Web with LDAP and other kinds of
directories, as well as other URI-based directory schemes like UDDI.”
Fellow ZapThink analyst Ronald Schmelzer
discussed the tackling of XRI with internetnews.com.
“The XRI idea is a good one, although it really conflicts with many of the
initiatives for using URLs within the context of Web Services. For example,
much of the purpose of UDDI is to facilitate the dynamic discovery and
binding to services that themselves are defined at specific URLs. Thus, the
URLs represent a specific binding location and UDDI should be the way to
isolate us from having to know those URLs ahead of time — an automated
search engine, to overly simplify things. However, XRI claims that they will
be working within the concept of URIs and directory services, such as UDDI.
But, the challenge is to get their XRI naming mechanism adopted by those
that facilitate creation and deployment of Web Services.”
Schmelzer said XRI could face major adoption challenges because Web services
superpowers — Microsoft, IBM, and Sun — are not behind it yet.
“Sure, things would work better if the universe used XRIs to identify
location-independent services, but it will require widespread and consistent
implementation. URLs were accepted because they started in an environment
where people weren’t using an alternate technology for identifying linkable
resources. Tim Berners-Lee invented the URL (URI) out of necessity. XRIs now
are emerging in an environment where URLs are everywhere. They will need to
figure out how to either co-exist or supplant this widespread naming
mechanism. My thought is that they will need support of the WS-I as well as
the ‘heavyweights’ IBM, Microsoft, Sun, BEA, and others to make this happen.
If you look at the list of participants, I don’t see any. This might be an
example of a great technology concept with major adoption challenges.”
