1 / 32

Rivier College CS575: Advanced LANs Gigabit Ethernet

Rivier College CS575: Advanced LANs Gigabit Ethernet. Overview. What is Gigabit Ethernet? Why Gigabit Ethernet Physical Layer Technologies Functional Elements of Gigabit Ethernet Technology Performance Issues Gigabit Ethernet Migration and Application Environments

corin
Télécharger la présentation

Rivier College CS575: Advanced LANs Gigabit Ethernet

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Rivier CollegeCS575: Advanced LANsGigabit Ethernet Gigabit Ethernet

  2. Overview • What is Gigabit Ethernet? • Why Gigabit Ethernet • Physical Layer Technologies • Functional Elements of Gigabit Ethernet Technology • Performance Issues • Gigabit Ethernet Migration and Application Environments • Vendor Implementation Examples Gigabit Ethernet

  3. What is Gigabit Ethernet? • An extension to 10 Mbps and 100 Mbps IEEE 802.3 Ethernet • Offering 1000 megabits per second data rate • An emerging IEEE 802.3z Ethernet standard • The first draft of the standard was produced by IEEE in January 1997 • The final standard was approved in June 1998 • Can be implemented in either hubs (repeaters) or switches • The hub is a shared medium technology (medium access control such as CSMA/CD is needed) and the switch is a dedicated medium technology (no medium access controls are needed) • Allows half-duplex (HDX) and full-duplex (FDX) operation at speeds of 1000 Mbps (2000 Mbps effective throughput for FDX) • Expected to be deployed initially as a backbone network as well as for high speed server connections Gigabit Ethernet

  4. What is Gigabit Ethernet? (concluded) • Evolutionary high speed network using existing standards and proven technology • Compatible with existing Ethernet • Unchanged Ethernet MAC Layer (CSMA/CD) protocol • Unchanged Ethernet frame format and frame size (both maximum and minimum) • Support existing star-wired topology • Support existing Ethernet applications Gigabit Ethernet

  5. Why Gigabit Ethernet? • Faster and more power computers continues to grow • The need for gigabit LAN backbone to interconnect faster LANs such as Fast Ethernet • Growing number of complex, time critical, and bandwidth intensive applications such large image file transfers • Capability to support new applications and data types such as voice and video • Easy migration to higher performance levels (from wide installation base of Ethernet/Fast Ethernet) without disruption (compare to ATM or other technologies) • Low cost of ownership including both purchasing cost and support cost • Internetworking and network design flexibility Gigabit Ethernet

  6. Applications Driving Network Growth Source: Gigabit Ethernet Alliance Gigabit Ethernet

  7. Physical Layer Technology • The Physical Layer technology for Gigabit Ethernet is mainly based on the ANSI X3T11 standards for Fibre Channel • Since Fibre Channel technology has been in use for for several years, the IEEE 802.3z standards committee decided to adopt this technology to reduce development time and risk for the Gigabit Ethernet standard • Four physical media types are defined for Gigabit Ethernet • Single mode fiber • Multimode fiber • Shielded twisted pair cable (STP) • Unshielded twisted pair (UTP-5) cable • Two Physical Layer standards • 1000BASE-X (IEEE 802.3z) • 1000BASE-T (IEEE 802.3ab) Gigabit Ethernet

  8. Physical Layer Technology (continued) • 1000BASE-X is based on Fibre Channel Physical Layer standard • Three media types included in 1000BASE-X • 1000BASE-SX: Short wavelength (850 nm) laser on multimode fiber • 1000BASE-LX: Long wavelength (1300 nm) laser on single mode and multimode fiber • 1000BASE-CX: Short haul copper “twinax” STP • 1000BASE-SX is targeted at lowest cost multimode fiber runs in horizontal and shorter backbone applications • 1000BASE-LX is targeted at longer multimode building fiber backbones and single mode campus backbones • 1000BASE-CX is used for interconnection of equipment within a short distance (25 m) in a computer room • Based on Fibre channel’s 8B/10B encoding (25% overhead) • 1.25 Gbps wire speed to achieve 1 Gbps data rate Gigabit Ethernet

  9. Physical Layer Technology (continued) 1000BASE-X Cable Type and Distances Source: Gigabit Ethernet Alliance Gigabit Ethernet

  10. Physical Layer Technology (continued) • 1000BASE-T Standard • A standard (IEEE 802.3ab) for Gigabit Ethernet over 4 pairs of Category 5 UTP for distance up to 100 meters • Based on the specifications of ANSI/TIA/EIA-568A (1995) • No need to replace existing Category 5 cabling (conforming to 1995 ANSI/TIA/EIA-568A standards) to use 1000BASE-T • Any link supporting 100BASE-TX should support 1000BASE-T • Installed cabling should be tested for return loss (echo), caused by impedance mismatches (typically the fault of of poor connectors) and far-end crosstalk (signal leakage from adjoining wire pairs at the far end of the transmitter creates electrical noise) • Uses a symbol rate of 125 Mbaud • uses a more sophisticated 4-dimensional, 5-level Pulse Amplitude Modulation (4D-PAM5) coding scheme Gigabit Ethernet

  11. Physical Layer Technology (concluded) • 4-levels to achieve 2 bits per symbol and the fifth level for Trellis Froward Error Correction coding • Supports FDX on each pair of Category 5 UTP Gigabit Ethernet

  12. Functional Elements of Gigabit Ethernet Technology Ethernet Upper Layers Media Access Control (MAC) Full duplex/ Half duplex Gigabit Media Independent Interface (GMII) 1000BASE-T Encoder/Decoder 1000BASE-X 8B/10B Encoder/Decoder 1000BASE-SX SWL Fiber Optic Tranceiver 1000BASE-CX Shielded Balanced Copper Tranceiver 1000BASE-LX LWL Fiber Optic Tranceiver 1000BASE-T UTP Category 5 Tranceiver 50 u MMF - 550 m 62.5 u MMF - 220 - 275m 9 u SMF - 5km 50 u MMF - 550 m 62.5 u MMF - 500 m 25 m 100 m 802.3ab physical layer 802.3z physical layer Gigabit Ethernet

  13. Performance Issues • Limitations of shared medium (HDX) Gigabit Ethernet • Without modification to the Ethernet MAC layer protocol, the maximum network diameter/size of Gigabit Ethernet is limited to about 20 m • To keep the maximum network diameter/size of Gigabit Ethernet to 200 m (same as Fast Ethernet), the minimum CSMA/CD carrier time and the Ethernet slot time have been extended to 512 bytes (should be 640 bytes) • Packets smaller than 512 bytes have an extra carrier extension • If all traffic consisting of 64-byte frames, the effective throughput would drop to 120 Mbps • The Gigabit Ethernet throughput would be between 300 - 400 Mbps for average frame size on most Ethernet in the 200- 500-byte range Gigabit Ethernet

  14. Performance Issues (continued) • Gigabit Ethernet switches must be used to extend network size • Not appropriate for seamless integration of LAN, MAN, and WAN • Doesn’t deliver the QoS guarantees needed by multimedia applications • Working on standards to provide Quality of Service (QoS) and Class of Service (CoS) to IP traffic • Use 802.1Q/p to provide priority information for frames in the network • Use 802.3x for flow control • QoS support by switch vendors such as Foundry Networks • Policy-based traffic classification on • Type of Service (ToS) • IP precedence mapping • Layer 2/3/4 defined traffic flow Gigabit Ethernet

  15. Performance Issues (continued) • Queue management • Strict Priority (SP) Queue • Weighted Fair Queue (WFQ) • 802.1p queue mapping Gigabit Ethernet

  16. Performance Issues (concluded) Source: Stallings: Data and Computer Communications Gigabit Ethernet

  17. Gigabit Ethernet Migration and Application Environments Fast Ethernet Switch to Switch Links Source: Gigabit Ethernet Alliance Gigabit Ethernet

  18. Gigabit Ethernet Migration and Application Environments (continued) UpgradingSwitch to Switch Links Source: Gigabit Ethernet Alliance Gigabit Ethernet

  19. Gigabit Ethernet Migration and Application Environments (continued) Fast Ethernet Switch to Server Links Source: Gigabit Ethernet Alliance Gigabit Ethernet

  20. Gigabit Ethernet Migration and Application Environments (continued) Upgrading Switch to Server Links Source: Gigabit Ethernet Alliance Gigabit Ethernet

  21. Gigabit Ethernet Migration and Application Environments (continued) Switched Fast Ethernet Backbone Source: Gigabit Ethernet Alliance Gigabit Ethernet

  22. Gigabit Ethernet Migration and Application Environments (continued) Upgrading Switched Fast Ethernet Backbone Source: Gigabit Ethernet Alliance Gigabit Ethernet

  23. Gigabit Ethernet Migration and Application Environments (continued) Shared FDDI Backbone Source: Gigabit Ethernet Alliance Gigabit Ethernet

  24. Gigabit Ethernet Migration and Application Environments (continued) Upgrading Shared FDDI Backbone Source: Gigabit Ethernet Alliance Gigabit Ethernet

  25. Gigabit Ethernet Migration and Application Environments (concluded) Upgrading High-Performance Desktops Source: Gigabit Ethernet Alliance Gigabit Ethernet

  26. Examples of Gigabit Ethernet Switches Extreme BlackDimaond Gigabit Ethernet Switch Foundry BigIron 4000 Gigabit Ethernet Switch Lucent P550 Cajun Switch Gigabit Ethernet

  27. Enterprise-Campus Network Example Source: Foundry Networks Gigabit Ethernet

  28. Traditional Router and Hub Campus Intranet Source: Cisco White Paper Gigabit Ethernet

  29. Traditional Campus Wide VLAN Design Source: Cisco White Paper Gigabit Ethernet

  30. Campus Wide VLAN with Multilayer Switching Source: Cisco White Paper Gigabit Ethernet

  31. Multilayer Model with Server Farm Source: Cisco White Paper Gigabit Ethernet

  32. W. Stalling, Local and Metropolitan Area Networks, 6th edition, Prentice Hall, 2000, Chapter 7 References W. Stalling, Data and Computer Communications, 6th edition, Prentice Hall, 2002, Chapters 13-14 A. Wu, Advanced Local Area Networks, Lectures & Slides, Rivier College, 2001. Gigabit Ethernet

More Related