*****  To join INSNA, visit http://www.sfu.ca/~insna/  *****

Here's a press release just out from Rennselaer Polytechnic University. It
cites a Science story but doesn't give the URL
 Barry
 ___________________________________________________________________

  Barry Wellman        Professor of Sociology       NetLab Director
  [log in to unmask]   http://www.chass.utoronto.ca/~wellman

  Centre for Urban & Community Studies        University of Toronto
  455 Spadina Avenue   Toronto Canada M5S 2G8   fax:+1-416-978-7162

  *** Now Out: _The Internet in Everyday Life_ (Blackwell, 2002) ***
 ___________________________________________________________________


Rensselaer Polytechnic Institute (RPI)
31-Jan-03


Uniting with Only a Few Random Links

Keywords: NETWORKS SYSTEMS PARALLEL COMPUTING SMALL-WORLD
Description: A Rensselaer Polytechnic Institute physics researcher has
found that "small-world networking"-- which links a computer to its
nearest neighbor and also a few other random computers in a group-- could
lead to faster, more accurate parallel-computing techniques for
simulation. (Science, 31-Jan-2003)

TROY, N.Y. - Researchers searching for information about highly complex
systems, such as the spread of diseases, the rise and fall of financial
markets, or cell-phone communication networks, benefit from large-scale
networked computer simulation.

These simulations are frequently implemented using large networks of
computers that break down the problem into many parts. Tackling weighty
problems, bit by byte, allows the simulation process to run faster --
sometimes.

The problem comes when the computers have to compare notes, says Gyorgy
Korniss, assistant professor of physics at Rensselaer Polytechnic
Institute. Korniss' solution is to use "small-world" networking -- which
links a computer to its nearest neighbor, and also a few other random
computers in the group. Korniss' findings are published in the Jan. 31
issue of the journal Science.

Korniss's research could lead to better parallel-computing techniques for
simulation. Parallel computing divides a task among many smaller computers
instead of one large one to do the job faster and more efficiently.

Typically, each computer in a network is connected to its closest
"neighbor." But getting information from the machine next door doesn't
allow each computer to get the whole picture of what the entire
neighborhood is doing. When one system is collecting data at a greater
pace than another, the result is a data traffic jam, causing a major
slowdown in the simulation process.

"Enormous amounts of additional time or memory are required for computers
to keep track of information they need from each other to create accurate
simulations," Korniss says.

The solution, according to Korniss, lies with creating a "small
world"-like communication network in which the individual computers
randomly "check in" with each other to make sure they are in sync.

"Our results indicate that only a few random links are necessary for each
computer to know how the network as a whole is behaving." Korniss adds.
"Many of us know the concept of six degrees of separation in which any one
person is only a few acquaintances away from anyone else. The same idea
can be applied to complex problem-solving network systems for more
effective large-scale model simulations."

Mathematicians Duncan Watts and Steve Strogatz at Cornell University were
the first to formulate the significance of small-world networks in
natural, artificial, and social systems in 1998.

Korniss' collaborators are Mark Novotny, professor at Mississippi State
University, Hasan Guclu, graduate student at Rensselaer, Zoltan Toroczkai,
technical staff member at Los Alamos National Laboratory, and Per Rikvold,
professor at Florida State University. The research is funded through the
National Science Foundation, the Research Corporation, and the U.S.
Department of Energy.

Rensselaer Polytechnic Institute, founded in 1824, is the nation's oldest
technological university. The school offers degrees in engineering, the
sciences, information technology, architecture, management, and the
humanities and social sciences. Institute programs serve undergraduates,
graduate students, and working professionals around the world. Rensselaer
faculty are known for pre-eminence in research conducted in a wide range
of research centers that are characterized by strong industry
partnerships. The Institute is especially well known for its success in
the transfer of technology from the laboratory to the marketplace so that
new discoveries and inventions benefit human life, protect the
environment, and strengthen economic development.

CONTACT: Gyorgy Korniss (518) 276-2555, [log in to unmask]

_____________________________________________________________________
SOCNET is a service of INSNA, the professional association for social
network researchers (http://www.sfu.ca/~insna/). To unsubscribe, send
an email message to [log in to unmask] containing the line
UNSUBSCRIBE SOCNET in the body of the message.