Putting a Business Suit on Grid Technology
Two initiatives hope to make grid computing—in which scattered computers are linked together to function as a single machine—more useful to businesses. Academia has used grid computing for many years.
One focus of the new efforts is to create industry standards, which experts believe are necessary to widen corporate adoption of grid technology. Another focus is explaining the details and benefits of efficiently implementing grid technology.
To conduct distributed computing on heterogeneous systems, grid-based applications use standardized interoperability technologies such as Web services. This approach features grid and application-specific services built on the WS-Resource Framework, which defines a family of specifications for accessing resources using Web services. They are supported by lower-level protocols such as WS-Security, used to provide secure Web services-based communications, and WS-Reliable Messaging, which enables dependable message delivery between distributed applications. The Enterprise Grid Alliance (www.gridalliance.org), a group of computing companies, plans to release white papers on how to make grids more practical for corporate use.
The EGA has also developed a common set of terms that all involved parties can use to help with the development of standards and the implementation of corporate grid systems.
The EGA is working closely with standards-related, grid-oriented, and other organizations, such as the Global Grid Forum. The alliance will rely on these organizations to create grid-computing specifications, said Paul Strong, chair of the EGA technical steering committee and a Sun Microsystems systems architect.
Today, most of the few companies doing grid computing use vendor-specific tools from companies such as Data Synapse, IBM, Oracle, and United Devices, said Jonathan Eunice, an analyst at Illuminata, a market research firm. Standards would help widen grid adoption by allowing system interoperability and providing common development criteria.
The Globus Alliance (www.globus.org), a consortium of grid researchers and research institutions, has released the open source Globus Toolkit 4.0 for writing applications that run on grid systems.
The toolkit manages distributed-computing and -storage resources. Companies could then build high-level enterprise grid-based applications atop the toolkit, explained Ian Foster, senior scientist and head of Argonne National Laboratory's Distributed Systems Lab and a member of the Globus Alliance's board of directors.
To conduct distributed computing on heterogeneous systems, Foster noted, the toolkit uses standardized interoperability technologies such as Web services and Grid FTP.
By letting companies distribute work among a system of computers, grid technology offers businesses versatility, agility, and improved efficiency, Strong said.
Grids can also help companies save money by performing tasks via the unused time of existing computers, rather than by buying new servers, he added. If a machine isn't used for a certain amount of time, the grid server can offload a job to it. When the workstation is used again, the system moves the task to an available computer.
Companies could use grid computing for problems that can be divided into pieces for assignment to multiple PCs, such as complex analytics, computation-heavy activities, and engineering applications with large or bursty workloads, explained Foster.
Unusual Attack Holds Computer Files for Ransom
Hackers have launched a new type of attack in which they remotely lock up documents on computers and demand a ransom from the victims to unlock them. Although this attack wasn't widespread, experts fear criminals could up the stakes.
Security researchers at Websense, a Web-filtering- and Web-security-software vendor, discovered the ransomware scheme when hackers victimized a corporate customer's computer and left a ransom note. The company declined to provide specifics about the victim or many details of the attack.
The attack infected computers when users visited a Web site vandalized by hackers who added malicious software to it by exploiting a Web-server or operating-system vulnerability.
Hackers then took advantage of a problem with the Internet Explorer help function that let them upload software to a victim's computer and then run it. Microsoft provided a patch for this problem last summer.
The attack used the vulnerability to infect victims' unpatched PCs with the Trojan.Pgpcoder Trojan horse. Once downloaded and run, this program downloads a second application that searches for and scrambles 15 file types, including word-processing documents, digital photographs, and spreadsheets.
The attack leaves a ransom note in the only readable text file left on the infected computer. According to Hubbard, the note contains instructions to send a message with a specific subject line to a designated e-mail address.
A reply then tells the victim to send hackers $200 via e-gold—an e-payment company—in return for the unscrambled files. Hubbard said the attackers probably asked for only $200 to encourage payment.
The attack used apparently is a form of weak obfuscation, which entails file scrambling, said Dave Cole, director of security product management for Symantec Security Response. The technique was sufficient to make it difficult for victims to get their files without either paying the attackers or obtaining expert assistance , he noted.
Investigators could follow the money trail, say security experts. However, Cole said, because law-enforcement agencies have limited resources and because no one has reported giving money to the attackers, police might not investigate the case unless it becomes more significant.
Experts said there were no reports that the new threat was spreading. In addition, the vandalized Web sites that spread the infection are no longer active. However, the problem is still significant because attackers could use e-mail or other means besides infected Web sites to distribute Trojan. Pgpcoder.
According to Cole, "This appears to be a proof-of-concept attack."
Security researchers worry that improved versions of the attack might be more dangerous and more difficult to either prevent or solve.
Schools Increasingly Use Software to Grade Essays
Schools are increasingly turning to software to analyze and grade student essays. Computers have long graded multiple-choice tests, which entail the easily automated task of matching a student's response to the correct answer. However, scoring essays is a more complex task involving a range of variables and requiring subtle analysis.
Software now scores a variety of written assignments, from high school papers to an essay that appears on the Graduate Management Admission Test (GMAT), the standard exam for US graduate business-school applicants.
Most essay-grading software analyzes sentences and paragraphs, looking for keywords and relationships between terms that indicate the writer has properly explained important concepts.
The systems use a number of technologies to determine how well an essay has met an assignment's requirements. These technologies include natural language understanding to recognize keywords and word patterns, case-based reasoning to help compare unanalyzed essay segments with analyzed segments, and machine learning to identify patterns that could help with the evaluation process.
Typically, these systems extract information from a pool of human-graded essays to develop their own comparable evaluation approaches.
e-Rater essay-grading software by ETS, a major educational-assessment company that offers the GMAT and other tests, can develop its grading techniques for an assignment by analyzing papers that aren't even necessarily on the assigned theme, explained Jill Burstein, ETS's principal development scientist.
"Most programs use statistical modeling to build a predictive model," explained Ed Brent, a University of Missouri sociology professor who designed SAGrader (pronounced "essay grader") software, which he uses to grade first drafts of papers in his introductory sociology classes.
SAGrader uses modeling to come up with the material that should appear in essays that properly address the assigned topic, including definitions of terms and supportive information, he said. The application also generates comments to students.
Frequently, to make essay-grading software work properly, teachers must prepare it for specific assignments, such as by entering keywords and important elements, taking into accounts different ways students might express them.
Proponents say essay-grading software reduces some of the subjectivity and tedious work that occurs when teachers grade papers. It also reduces grading-related overtime costs, noted Stan Jones, Indiana's commissioner of higher education. Indiana high schools are using software to grade year-end English assessments for 60,000 juniors. Jones noted that the machines tend to grade the essays "marginally higher" than teachers.
Skeptics have said that using software to grade essays would encourage students to figure out ways to trick the technology, such as by scattering obvious keywords or phrases meaninglessly throughout a paper.
News Briefs written by
Linda Dailey Paulson, a freelance technology writer based in Ventura, California. Contact her at ldpaulson@yahoo.com.
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