APPLICATIONS

Two organizations have recently recognized Pittsburgh Supercomputing Center (PSC) senior network engineering specialist, Matt Mathis, for his network research. In August, the Special Interest Group on Data Communication (SIGCOMM), of the Association for Computing Machinery (ACM), notified Mathis that he will receive their Test of Time Award. ACM SIGCOMM is the leading forum for professional discussion of data communications and computer networks. The award recognizes Mathis’s 1997 paper, co-authored with former PSC staff members Jamshid Mahdavi and Jeff Semke and with Teunis Ott (then at Bellcore, now at the New Jersey Institute of Technology), “The macroscopic behavior of the TCP congestion avoidance algorithm.” The paper was published in the ACM journal Computer Communication Review. The Test of Time Award honors papers from 10 to 12 years ago in CCR deemed by a committee to be “an outstanding paper whose contents are still a vibrant and useful contribution today.” In October, Cisco System’s Collaborative Research Initiative presented an unrestricted gift of $65,500 to Carnegie Mellon University to support Mathis's research proposal titled “Rebalancing Internet Congestion Control.” The project will explore the possibility of changing how the Internet manages traffic. “Our goal,” says Mathis, “is to shift responsibility for allocating network capacity from the end-systems to the network itself, such that the network can support the safe operation of diverse control algorithms.” Mathis has been a network engineer at PSC since 1988. His network research includes Network Path and Application Diagnosis (NPAD), which assembled tools and resources to enable people who aren’t necessarily network experts to quickly diagnose and correct most flaws that affect users connected to high-speed networks. He helped to lead PSC research efforts in the Web100 and Net100 projects. In Web100, a team that included the National Center for Atmospheric Research (NCAR) and the National Center for Supercomputing Applications (NCSA), with funding from NSF and Cisco Systems, developed software to “tune” the Internet protocol in computer operating systems to better exploit available network bandwidth. This software is now used in the Linux operating system and is incorporated in many research projects nationwide. In the related Net100 project, funded by the U.S. Department of Energy, Mathis and others of PSC’s network group collaborated with Lawrence Berkeley National Laboratory, Oak Ridge National Laboratory and NCAR to create software tools that allow operating systems to tune themselves in response to changing conditions on the network. Mathis has participated in authoring several RFCs, official standards of the Internet Engineering Task Force, an open international community of network designers, operators, vendors, and researchers concerned with evolution and operation of the Internet. In 2007, Mathis and PSC engineer John Heffner authored “Packetization Layer Path MTU Discovery,” a new standard for improved Internet performance, which describes a method to automatically assess the best Maximum Transfer Unit (MTU) — the biggest data packet a connection can efficiently use — for a given network connection. Also in 2007, Mathis, Heffner and Rajiv Raghunarayan of Cisco published “TCP Extended Statistics MIB.” This important standard, an outcome of the Web100 project, describes extended performance statistics for TCP (transmission control protocol), a core software protocol that underlies the majority of Internet applications. With the performance statistics defined by this document, diagnostic tools can — in situations of poor network performance — directly ask TCP why it is slow and gather information on the nature of the problem.