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As the Information Age connects the world, researchers endeavor to understand and improve the performance of the networks that bridge continents, countries, and cultures. The Measurement and Network Analysis group of the National Laboratory for Applied Network Research (NLANR/MNA) at the San Diego Supercomputer Center (SDSC) at UC San Diego is playing an important role in an international project that is successfully linking scientists in the US, Canada, Russia, China, Korea, and the Netherlands with high speed network services.

The Global Ring Network for Advanced Applications Development (GLORIAD) project is giving scientists around the world advanced networks for communication and data exchange, making possible active, daily international collaboration on problems from weather forecasting, astronomy, and earthquake prediction to joint telemedical applications and classroom-to-classroom cooperation. According to Greg Cole, GLORIAD principal investigator, the project considers their partnership with SDSC's Active Measurement Project (AMP) a core component of GLORIAD's work in developing a solid international measurement infrastructure.

Ongoing efforts by Ronn Ritke, Co-Principal Investigator of NLANR/MNA and Tony McGregor, AMP Project Manager, have led to deploying the first Active Measurement Project (NLANR/AMP) monitor at the Computer Network Information Center (CNIC) of the Chinese Academy of Science in Beijing, which is already proving quite useful. The growing international AMP "mesh" allows the researchers to view problems in network infrastructure as well as to highlight progress. For example, the Chinese AMP data has documented the improvement in roundtrip packet time between Beijing and Tokyo, which has dropped from around 300 milliseconds to 90 milliseconds with the upgraded network infrastructure that Chinese and Japanese partners are implementing.

International collaborations require persistent person-to-person initiatives, and current efforts by Ritke and his colleagues include discussions with the CNIC on deploying as many as seven additional AMP monitors in China. In addition, the first AMP box has been delivered by GLORIAD researchers to Russia for study and eventual deployment at the Moscow central POP facility. Other GLORIAD partners, including the Korea Institute of Science and Technology Information (KISTI), SURFnet in the Netherlands, and CANARIE in Canada, are also making use of AMPs to monitor their networks.

The network analysis infrastructure created by the National Science Foundation-funded NLANR/MNA group, based at SDSC, is used for their own research and also supports the efforts of a growing number of outside researchers, system administrators, and students such as those in GLORIAD, who are enthusiastically collaborating with NLANR/MNA researchers. The NLANR/MNA research infrastructure now spans five continents, and as the GLORIAD ring network connecting the U.S., China, and Russia becomes fully operational, it will circle the globe. In addition to GLORIAD, the AMP project is a key part of networking efforts such as TranPAC2 and WHREN-LILA, where research with AMPs is also underway.

Network measurements are crucial for identifying and locating problems such as malfunctions, bottlenecks, inefficiencies, and incompatibilities in ultrafast research networks and high-speed international links. The NLANR/MNA researchers assess network performance by measuring the flow of message traffic and analyzing performance issues. The AMP project carries out site-to-site active measurements and analyses by inserting test messages into the networks and observing the progress of the messages through the systems. The measurement devices for the AMP project are rack-mounted PCs with high-speed network cards, installed in the network equipment racks of participating universities and research institutions.

More than 160 AMP monitors are deployed on high-speed research networks in the US and other countries. The monitors exchange messages with other monitors on the network, tracking the messages to determine such factors as routing pathways, round-trip times, and packet loss between sites. In addition to gathering data, the AMP project also analyzes long-term, large-scale trends in message flow patterns.

The group makes all data, analyses, and tools available to the network engineering and research community worldwide to ensure that networks can be tuned for maximum end-to-end performance. All participation is voluntary, and both NLANR/MNA and participating sites are meticulous about maintaining the privacy of network users. To do this, the researchers collect statistics about the message traffic, but don't read the content of any messages. If they were working with the Post Office instead of high-speed networks, their devices would be sending postcards to each other and reading only the postmarks on their own mail, while completely ignoring all other mail.