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An Assessment of Gigabit Ethernet Technology and Its Applications at the NASA Glenn Research Center

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An Assessment of Gigabit Ethernet Technology and Its Applications at the NASA Glenn Research Center NASA / TMm2000-209803 An Assessment of Gigabit Ethernet Technology and Its Applications at the NASA Glenn Research Center Catherine Murphy Bakes Kent Sate University, Kent, Ohio Chan M. Kim and Calvin T. Ramos Glenn Research Center, Cleveland, Ohio February 2000 The NASA STI Program Office... in Profile Since its founding, NASA has been dedicated to CONFERENCE PUBLICATION. Collected the advancement of aeronautics and space papers from scientific and technical science. The NASA Scientific and Technical conferences, symposia, seminars, or other Information (STI) Program Office plays a key part meetings sponsored or cosponsored by in helping NASA maintain this important role. NASA. The NASA STI Program Office is operated by SPECIAL PUBLICATION. Scientific, Langley Research Center, the Lead Center for technical, or historical information from NASA's scientific and technical information. 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Scientific [email protected] and technical findings that are preliminary or of specialized interest, e.g., quick release • Fax your question to the NASA Access reports, working papers, and bibliographies Help Desk at (301) 621-0134 that contain minimal annotation. Does not contain extensive analysis. • Telephone the NASA Access Help Desk at (301) 621-0390 CONTRACTOR REPORT. Scientific and technical findings by NASA-sponsored Write to: contractors and grantees. NASA Access Help Desk NASA Center for AeroSpace Information 7121 Standard Drive Hanover, MD 21076 NASA/TMm2000-209803 An Assessment of Gigabit Ethernet _echnology and Its Applications at the NASA Glenn Research Center Catherine Murphy Bakes Kent Sate University, Kent, Ohio Chan M. Kim and Calvin T. Ramos Glenn Research Center, Cleveland, Ohio National Aeronautics and Space Administration Glenn Research Center February2000 Acknowledgments The authors would like to thank David Pleva and Raymond Schutz for their active participation in many discussions regarding Gigabit Ethernet and for their helpful comments and Suggestions. This research was supported by the High Performance Computing and Communication Project (HPCCP) at the NASA Glenn Research Center. Available from NASA Center for Aerospace Information National Technical Information Service 7121 Standard Drive 5285 Port Royal Road Hanover, MD 21076 Springfield, VA 22100 Price Code: A03 Price Code: A03 An Assessment of Gigabit Ethernet Technology and Its Applications at the NASA Glenn Research Center Catherine Murphy Bakes Kent State University Department of Administrative Sciences College of Business Administration Kent, Ohio 44242 Phone: (330) 672-2750 Ext. 338, Fax: (330) 672-2448 Email: [email protected] Chan M. Kim and Calvin T. Ramos National Aeronautics and Space Administration Glenn Research Center Cleveland, Ohio 44135 Abstract: This paper describes Gigabit Ethernet and its role in supporting R&D programs at NASA Glenn. These programs require an advanced high-speed network capable of transporting multimedia traffic, including real-time visualization, high-resolution graphics, and scientific data. GigE is a 1 Gbps extension to 10 and 100 Mbps Ethemet. The IEEE 802.3z and 802.3ab standards define the MAC layer and 1000BASE-X and 1000BASE-T physical layer specifications for GigE. GigE switches and buffered distributors support IEEE 802.3x flow control. The paper also compares GigE with ATM in terms of quality of service, data rate, throughput, scalability, interoperability, network management, and cost of ownership. 1. Introduction As application integration, distribution, and collaboration have become more common in the network computing environment, the demand for better, faster networking technologies has grown. Not only do many of today's emerging applications demand higher bandwidth, but they also require better service in terms of quality, reliability, and security. Only a few years ago, many campus network infrastructures consisted of shared 10 Mbps Ethernet technologies and employed software-based routing. The majority of the traffic stayed within a department's local boundary and typical applications, such as electronic mail, file transfers, and printing, cooperatively shared the available bandwidth. With the development of Application Specific Integrated Circuit (ASIC) technology and communication protocol standards, high performance switches with improved services have become the most popular solution to meet new challenges in network computing. 10/100 Mbps switched Ethernet/Fast Ethernet is replacing concentrator- based 10Base-T shared Ethernet and Layer 3 switches boast wire-speed routing capabilities. Also, Asynchronous Transfer Mode (ATM) has brought a new paradigm in networking technology through its OC-3/OC-12 speeds, voice-data integration, and superb quality of service. On the Ethernet side, 1000 Mbps Gigabit Ethernet technology has made substantial progress in many key standards issues and, due to its relative simplicity and low-cost, has gained favorable support from network professionals as a formidable choice for the next generation of Local Area Network (LAN) technology. NASA/TM--2000-209803 1 This paperdealswith an overviewof Gigabit Ethernetnetworktechnologyandits role in supportingresearchanddevelopmentactivitiesat the NASA Glenn ResearchCenter.NASA's current missionrevolvesaroundfour strategicenterprises,i.e., spacescience,missionto planet earth,humanexplorationand developmentof space,and aeronauticsand spacetransportation technology.TheNASA GlennResearchCenteris actively involvedin manyof theseenterprises through in-houseresearchand collaborationwith various governmentalagencies,universities, andindustry(Bakes,et al., 1996). In order to supportNASA Glenn's scientific missions,both computingand networking infrastructureshaveto provide adequatespeed,quality, andreliability. The computingresources at NASA Glenn include desktopworkstationsand serversbasedon either Windows or Unix operating systems, plus a few LINUX systems that have been deployed recently. For computationally intensive scientific and engineeringapplications,a cluster of serverswith multiple processorsis utilized. A typical desktop workstation, in order to run necessary applications,is connectedto serversthrougha high speednetwork.In additionto scientific and engineeringapplications,many mission-critical applications,such as file transfers,back-ups, web access,andelectronicmail, occupya largeportion of the network's traffic. At theheart of all theseapplicationsis the campusbackbonenetwork, which providesa variety of servicesto reliably deliver highthroughputtransportof critical data. Optical fiber is thetransmissionmediumusedfor the campusbackbonethat carrieslocal traffic betweenbuildings at NASA Glenn. This network includesmany strandsof single mode and multimode fiber and allows any attachedstation to accessa potential bandwidthranging from 100sof Mbps to multiple Gbps.Thebackboneinterfacesto variousfiber, coaxialcable,and copper local area networks within buildings and has been extendedto selectedserversand researchers'workstationsthat requirehigh-speedconnectivity.To furtherexploit the benefitsof fiber, thepublic Wide Area Network (WAN) providershaveinstalledfiber throughouttheentire geographicareaof interestto the Glenncommunity. This enablesGlenn researchersto access remotesitesfrom their desktopworkstationsandenablesusersat remotesitesto accessGlenn facilities via a seamlessfiber network at dataratesup to andbeyond155Mbps. Futurenetwork initiativeswill includeGbpsspeeds,especiallyfor backbones. TheNASA GlennResearchCenterhas activeprogramsin computationalaerodynamics, materialscience,structuredynamics,spacecommunication,andspacesciences.Theseprograms require a communicationsnetwork capable of transporting multimedia traffic, real time visualization,and data collected from scientific experiments.The diversetasksperformedby powerful desktopworkstations,local clusters,andcentralserversalsoplacea largedemandon the network. In addition, NASA Glenn's researchcommunityis developingthenext generation of computing applications and exploring tiaeir network
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