Evolving the Internet

Princeton-supported network serves as testing ground

By Steven Schultz

Princeton NJ -- Princeton Researchers are helping to develop an experimental global network of computers that is expected to become a testing ground for a future generation of the Internet.

Larry Peterson, chair of Princeton's computer science department  

Larry Peterson, chair of Princeton's computer science department, is a founder of PlanetLab, an experimental global computer network designed to help shape a future generation of the Internet.


The network, called PlanetLab, is designed to allow researchers to develop and test powerful new types of software that are not confined to a single computer but run on many computers at once, treating the global network, in a sense, as one large, widely distributed computer.

Once fully developed, such a network could yield many benefits, from faster downloads to more powerful search engines. A person watching an online video, for example, might receive it from many computers that work together to avoid congested parts of the Internet. Software that scans the entire Internet for malicious behavior could catch problems before they could be detected by a single computer at one particular site.

"If I can observe the behavior of the Internet from multiple vantage points, I can see what the traffic looks like, where the losses are and where the congestion is," said Larry Peterson, chair of Princeton's computer science department and one of the founders of PlanetLab.

In its initial stages, PlanetLab is expected to be most useful as a vehicle -- open to any researcher in industry or academia -- for testing globally distributed applications. Previously, researchers relied on network simulation, or a cluster of computers in a single room or building. With PlanetLab, which is built onto the Internet as an "overlay" network, researchers have a real-life testing ground that would be impossible for any single institution or company to create, said Peterson. "The Internet is much flakier than a controlled machine room," he said. "And it's just not practical for any one researcher to have hundreds of machines spread all over the world."

The PlanetLab project began in March 2002 when researchers from several institutions met to discuss the idea. The founding group included David Culler of Intel and the University of California-Berkeley, Tom Anderson of the University of Washington and Peterson. Intel, the world's largest computer chip maker and a manufacturer of networking products, provided seed grants of equipment to set up an initial network of 100 computers, which are hosted by 60 international institutions that quickly joined the project. The technology firms HP and Google also are joining the project and will commit resources to it.

Princeton recently has committed to hosting a formal consortium of PlanetLab users and developers. The University will provide administrative and technical support as the system grows toward a goal of 1,000 nodes worldwide.

"PlanetLab is unlike any other collaborative research effort I've been involved in," said Peterson. "It has an energy much like existed in the earliest days of the Internet. Researchers are using PlanetLab as a platform for advancing their individual research agendas, but at the same time, they are looking for opportunities to contribute to PlanetLab's core infrastructure. If I had to put my finger on the key idea in the architecture, it's that we have designed PlanetLab to provide a level playing field for innovation, and the research community has responded in force."

PlanetLab researchers believe the project will help the Internet evolve beyond a simple structure for transmitting data from place to place and toward a system that can manipulate the data before and after it travels. It is a first step toward an Internet that has processing power built into the infrastructure of the network. Because it is so decentralized, the Internet cannot change overnight. But if PlanetLab demonstrates value, companies that sell Internet hardware might begin to work aspects of the system into their products, said Peterson.


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