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DAILY NEWS AND INFORMATION
FOR THE GLOBAL GRID COMMUNITY /
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Special Features:
THE RISE OF THIRD-GENERATION
GRIDS
By Charlie Catlett, Global Grid Forum Chairman
When technology first breaks out of the research world it usually has a
cool
new name. In the 1980s people asked, "What's a Supercomputer?" In the early
1990s, it was, "What is the Internet?" In the end, the definition was less
important than the practical benefit the technology brought to real
applications, both scientific and commercial (and usually in that order). The
reason people have stopped asking for definitions of supercomputers or the
Internet today is not because someone finally wrote a good definition, but
because high performance computing and networking technologies have become
commodities. Standards are enablers to this transition, not definitions. We
can build supercomputers out of commodity PC's today because of standards, and
we can build Internets today because of standards.
I believe we are entering a new phase of Grid computing where standards
will
define Grids in the same way –- by enabling Grid systems to become easily-
built commodity systems. I'm going to call standard Grid systems "Third-
Generation Grids," or 3G Grids.
First generation "1G Grids" involved local "Metacomputers" with basic
services
such as distributed file systems and site-wide single sign on, upon which
adventurous software developers created distributed applications with custom
communications protocols. Gigabit test beds extended 1G Grids across distance,
and attempts to create "Metacenters" explored issues of inter-organizational
integration. 1G Grids were totally custom made, top to bottom -- proofs of
concept.
2G Grid systems began with projects such Condor, I-WAY (the origin of
Globus)
and Legion (origin of Avaki), where underlying software services and
communications protocols -- plumbing -- could be used as a basis for
developing distributed applications and services. 2G Grids offered basic
building blocks, but deployment involved significant customization and filling
in lots of gaps. Independent deployments of 2G Grid technology today involve
enough customized extensions that interoperability is problematic, and
interoperability among 2G Grid systems is very difficult. That's why we need
3G Grids.
The GGF community is taking lessons learned from 1G and 2G Grids and from
web
services technologies and concepts to create 3G architectures like the Open
Grid Services Architecture (OGSA), whereby a set of common interface
specifications supports the interoperability of discrete, independently
developed services. The recently released Open Grid Services Infrastructure
(OGSI) service specification is the keystone in this architecture.
By introducing standard technical specifications, 3G Grid technology will
have
the potential to allow both competition and interoperability not only among
applications and toolkits, but among implementations of key services. You know
that you've got a commodity when you can mix and match components. But this
potential won't be achieved by a better definition for "Grids" and it
certainly will take more than coining a term like 3G Grids. It will only come
if the community continues to work hard at defining standards. That is what
GGF is all about.
GGF "Grid Connections" Fall Issue is online at
www.ggf.org/L_News/Newsletter/Grid%20Connections/grid_connections_fall_03.pdf.
Global Grid Forum is online at www.globalgridforum.org/.
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