Large-scale attacks on computer networks are growing significantly, according to Arbor Networks’ Fourth Annual Worldwide Infrastructure Security Report, released this morning. At the same time, the types of attacks are becoming more diverse and more sophisticated, the report says.

The report, which can be downloaded free from the company’s Web site, is based on a survey of network operators that included a number of academic organizations. Almost a third of those surveyed said that fighting spam consumes the most resources, followed by preventing threats from “constant background activity” (such as worms and scans) and avoiding distributed denial-of-service attacks. Looking ahead to the next 12 months, the network operators said they were most worried about attacks from bots and botnets and from DNS-cache poisoning.

The increasing scale of distributed denial-of-service attacks is...

As part of today’s Olive Harvest Festival at the California Institute of Technology, a Caltech administrator named Thomas N. Mannion is giving a tour during which he will show people how to “find, recognize, and prepare the plants and herbs around campus.” For those who can’t make the tour — and as a reference tool for those who can — Mr. Mannion has also created a Google Earth map of edible and medicinal plants on the campus.

The map not only offers directions — to orange, lemon, lime, tangerine, and grapefruit trees; to grapes, figs, passion fruit, pumpkins, and wild strawberries; to asparagus, arugula, chives, lavender, and carob — but clicking on an icon pops open a box with photos of the relevant plant and information about it. The Mexican fan palm, for instance, “bears fruit that is not a date but similar,” the map says. “It is a spherical, blue-black, thin-fleshed fruit with one...

Researchers at the Georgia Institute of Technology have created a robot, named El-E, that can perform 10 of the 70-plus tasks that service dogs normally perform for people with physical impairments.

Like a service dog, El-E can heed voice commands. But instead of watching a human’s gestures for visual clues to accompany each command, the robot follows a laser-pointer beam to learn what object the command refers to. The laser might point, for instance, to a door handle to be opened or an item to be brought to the person delivering the command.

Charles C. Kemp, an assistant professor of biomedical engineering at Georgia Tech, is director of the Healthcare Robotics Lab, which developed the robot (the lab is a joint undertaking between Georgia Tech and Emory University). Mr. Kemp says his team studied a golden retriever named Betty for clues in creating the robot. He notes that while a...

A new building at the U. of Illinois will house a high-powered supercomputer. (U. of Illinois image)

The University of Illinois at Urbana-Champaign will break ground Wednesday for an 88,000-square-foot building to house a new petascale supercomputer that it plans to bring online in 2011. The IBM machine, for which the National Science Foundation is giving the university a $208-million grant, will be called Blue Waters and “will have greater computing capacity than all the current Top 500 supercomputers combined,” according to John R. Melchi, senior associate director for administration at the National Center for Supercomputing Applications, which will oversee the machine.

The $72.5-million building’s 20,000-square-foot machine room will have space enough for both the petascale machine and whatever machine comes after it. The building will also house about 40 staff members and...

Updated at 3:30 p.m.

The U.S. Education Department has chosen five companies to take part in a $300-million upgrade of the Web site students visit to complete a key federal financial-aid application.

Accenture Ltd., Computer Science Corp., Lockheed Martin Corp., Science Applications International Corp. and Vangent Inc. have won the right to compete for elements of the modernization, according to Washington Technology.

Students use the department’s Web site to complete the Free Application for Federal Student Aid, or Fafsa. The form not only allows students to apply for federal grants and loans, but also serves as the basic information-gathering tool for a host of other aid programs, including those of colleges and states. The Web site lets students create their own password-protected accounts, collect relevant information in one place, and calculate both their college costs and...

Seismologists at the University of California at Riverside and Stanford University are creating an earthquake-detection network on the cheap by using distributed-computing technology to link up laptop computers that have built-in motion sensors. The researchers’ Quake-Catcher Network has already detected several quakes — in Nevada in April and in Los Angeles in late July.

The system is the brainchild of Elizabeth Cochran, an assistant professor of seismology at Riverside. Volunteers download special software that quickly reports sudden motions to a central server on the Internet. If the server receives reports of sudden motions from several computers in different places simultaneously, it determines that an earthquake probably caused them.

Laptop manufacturers have been adding motion sensors — accelerometers — that protect data by turning off machines’ hard drives in case the machine...

The Hubble Space Telescope’s wide-field planetary camera, which astronomers have come to think of as an essential research tool, could be back in business as early as tomorrow now that the telescope’s managers have succeeded in switching on a backup computer that formats data for transmission to earth.

According to reports in the Los Angeles Times and elsewhere, engineers at the National Aeronautics and Space Administration’s Goddard Space Flight Center were able to boot up the backup machine — unused for the past 18 years — after a couple of false starts. The wide-field planetary camera, the telescope’s main imaging device, could resume sending pictures as early as tomorrow, NASA officials said.

The Hubble Space Telescope, carried into space aboard the shuttle Discovery in 1990, has long ...

A federal judge in Philadelphia sentenced a University of Pennsylvania student who directed large-scale botnet attacks to three months in jail and nine months of confinement in a halfway house and at home, according to a report on The New York Times’ Web site.

The student, Ryan Goldstein, will be on probation for five years. He also will be required to pay the government a $30,000 fine and to pay the university $6,100 in restitution because one of its servers crashed while Mr. Goldstein was using it to conduct an attack using a 50,000-machine botnet. A botnet is a network of computers that have been made into digital zombies controlled by a hacker or hackers.

After negotiating with prosecutors, Mr. Goldstein pleaded guilty in February to charges of aiding and abetting another computer hacker to break into a computer remotely. He could have been sentenced to up to six months in jail....

The University of Virginia’s Institute for Advanced Technology in the Humanities will help the Colonial Williamsburg Foundation develop interactive digital re-creations of five of the town’s historic sites as they appeared in 1776.

The three-dimensional models, intended for use by researchers as well as the general public, will incorporate “the wealth of historical documentation amassed by Williamsburg scholars,” the foundation said in a news release. The project is being paid for by a $943,000 grant from the federal government’s Institute of Museum and Library Services.

Jim Horn, Colonial Williamsburg’s vice president of research and historical interpretation, said that creating detailed virtual tours would be “extremely helpful to museums seeking to enrich visitors’ on-site experiences with a compelling online experience and will be of great benefit in expanding museum audiences, ...

Yale University is adding eight courses to its free online offerings, the university announced.

The courses, which were recorded as taught, are available in video and audio formats from the Open Yale Courses Web site, which the university says is among the most often visited of all its Web pages. For each course the university also posts searchable transcripts, syllabi, reading assignments, and additional materials such as problem sets.

Seven courses were already online. The new additions are: “Frontiers of Biomedical Engineering,” taught by W. Mark Saltzman; “Game Theory,” taught by Benjamin Polak; “Financial Markets,” taught by Robert Shiller; “Milton,” taught by John Rogers; “The American Novel Since 1945,” taught by Amy Hungerford; “The Civil War and Reconstruction Era,” taught by David Blight; “Introduction to Ancient Greek History,” taught by Donald Kagan; and “France Since 187...