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Gigabit Ethernet Comes of Age

Scaling Network Performance to 1000 Mbps

Gigabit Ethernet Comes of Age
Scaling Network Performance to 1000 Mbps Contents
Factors Driving Network Bandwidth What Is Gigabit Ethernet? Why Gigabit Ethernet? Gigabit Ethernet Delivers Cost-Effective 1000 Mbps Ethernet Performance Gigabit Ethernet Leverages Ethernet Equipment CostsThe Gigabit Ethernet Standard Leveraging Experience and Expertise: Lowering the Cost of Ownership (box) Gigabit Ethernet Cabling and Distance Specifications Multimode vs. Single-Mode Fiber Cabling (box) Implementing Gigabit Ethernet in the Network Gigabit Ethernet and Link Aggregation Optimizing Servers to Handle Gigabit Ethernet PCI Bus Bandwidth Network Operating System CPU Utilization atGigabit Speeds Memory Subsystems Partnering Gigabit Ethernet with ATM in Enterprise Networks (box) Guidelines for Using Gigabit Ethernet and ATM (box) Storage Subsystems Gigabit Ethernet and Layer 3 Switching Gigabit Ethernet Migration Scenario Summary For Further Reference 2 2 3 4 4 4 5 6 8 8 8 9 9 10 10 11 11 11 12 12 12 13 15

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Gigabit Ethernet Comes of Age
Scaling Network Performance to1000 Mbps Acronyms and Abbreviations
ASIC application-specific integrated circuit ATM Asynchronous Transfer Mode CoS Class of Service CPU central processing unit CSMA/CD carrier sense multiple access/collision detection FDDI Fiber Distributed Data Interface GbE Gigabit Ethernet GBIC gigabit interface connector GMII Gigabit Media Independent Interface IEEE Institute of Electrical and ElectronicsEngineers IP Internet Protocol MAC media access control MAN metropolitan area network MM multimode MTU maximum transmission unit

Is there a cost-effective way to accommodate exploding application and user bandwidth demands on network backbones while limiting network complexity? This white paper presents 3Com’s strategy for IT managers faced with bandwidth capacity constraints and consideringmigrating to a Gigabit Ethernet (GbE) technology solution. The paper briefly examines the forces driving the adoption of Gigabit Ethernet, the concepts behind the technology, and the key advantages of implementing Gigabit Ethernet over other technologies. The paper also explains the recently ratified Institute of Electrical and Electronics Engineers (IEEE) 802.3z Gigabit Ethernet standard andaccompanying cabling specifications and their significance in network implementation. Finally, the paper covers some important deployment issues and presents an incremental migration path to a Gigabit Ethernet infrastructure.
Factors Driving Network Bandwidth Progress is relentless; new technologies spur new application development, and new applications, in turn, fuel the need for further technologyadvancements. In a relatively short time span, network connections have evolved from shared or switched Ethernet to shared or switched Fast Ethernet to accommodate rising bandwidth demand. Within the enterprise networks, business applications are now advancing to embrace high-resolution graphics, video, and other rich media types that exceed the capacity of even Fast Ethernet performance. This latestgeneration of bandwidth-intensive applications can be organized into four categories: • Scientific modeling, publication, and medical imaging applications produce multimedia and graphics files that are ballooning in size from megabytes to gigabytes to terabytes. • Internet and intranet applications create unpredictable any-to-any traffic patterns. Increasingly, with servers distributed across theenterprise and users accessing Web sites inside and outside the corporate network,

there is no way to predict where traffic will go. • Data warehousing and backup applications handle gigabytes or terabytes of data distributed among hundreds of servers and storage systems. • Bandwidth-intensive groupware applications such as desktop video conferencing, interactive whiteboarding, and real-time...