1 / 51

Modern Ethernet

Modern Ethernet. Chapter 5. Objectives. Describe the varieties of 100-megabit Ethernet Discuss copper- and fiber-based Gigabit Ethernet Compare the competing varieties of 10-Gigabit Ethernet. Overview. Three Parts to Chapter 5. 100-megabit Ethernet standards Gigabit Ethernet standards

gala
Download Presentation

Modern 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. Modern Ethernet Chapter 5

  2. Objectives • Describe the varieties of 100-megabit Ethernet • Discuss copper- and fiber-based Gigabit Ethernet • Compare the competing varieties of 10-Gigabit Ethernet

  3. Overview

  4. Three Parts to Chapter 5 • 100-megabit Ethernet standards • Gigabit Ethernet standards • 10-Gigabit Ethernet standards

  5. Ethernet Facts • There are only four Ethernet speeds: 10 mega-bit, 100 megabit, 1 gigabit, and 10 gigabit • Every version of Ethernet uses either unshield-ed twisted pair (UTP) or fiber-optic. (With a few, rare exceptions) • Every version of Ethernet uses a hub or switch, although hubs are incredibly rare today.

  6. Ethernet Facts (continued) • Only 10- and 100-megabit Ethernet may use a hub. Gigabit and 10-Gigabit Ethernet networks must use a switch. • Every version of Ethernet has a limit of 1024 nodes. • Every UTP version of Ethernet has a maximum distance from the switch or hub to the node of 100 meters.

  7. 100-Megabit Ethernet

  8. 100BaseT • 100BaseT4 • CAT 3 or better cabling • Uses all four pair of wires • Disappeared from the market after 100BaseTX generally accepted • 100BaseTX • Dominant 100-megabit standard by the late 1990s • The term “100BaseT” now applies to this standard

  9. 100BaseTX Summary • Speed: 100 Mbps • Signal type: Baseband • Distance: 100 meters between the hub and the node • Node limit: No more than 1,024 nodes per hub • Topology: Star bus topology: physical star, logical bus • Cable type: Uses CAT5(e) or better UTP cabling with RJ-45 connectors

  10. Upgrading 10BaseT network to 100BaseT • CAT 5 cable or better • Replace all old 10BaseT NICs with 100BaseT NICs • Replace 10BaseT hubs or switches with 100BaseT hubs or switches • Multispeed, auto-sending NICs and hubs/switches ease the upgrade

  11. Multispeed, autosensing NIC • When first connected, it negotiates automatically with the hub or switch • If both do 100BaseT, they will use that mode • If the hub/switch only does 10BaseT, NIC does 10BaseT

  12. Figure 5.1 Typical 100BaseT NIC

  13. Figure 5.2 Auto-negotiation in action

  14. Distinguishing 10BaseT NIC from 100BaseT NIC • Inspect closely • Look for something indicating the card’s speed • All modern NICs are multispeed and auto-sensing

  15. Figure 5.3 Typical 100BaseT NIC in Vista

  16. 100BaseFX • UTP versus fiber-optic • UTP cannot meet the needs of every organization • 100-meter distance limit inadequate for large buildings and campuses • Lack of electrical shielding • Easy to tap • Fast Ethernet refers to all the 100-Mbps Ethernet standards

  17. 100BaseFX Summary • Speed: 100 Mbps • Signal type: Baseband • Distance: Two kilometers between hub and node • Node limit: No more than 1,024 nodes per hub • Topology: Star bus topology: physical star, logical bus • Cable type: Uses multimode fiber cabling with ST or SC connectors

  18. Full-Duplex Ethernet • Early 100BaseT NICs were half-duplex • Could both send and receive data • But not at the same time • IEEE added full-duplex to the standard • Device sends and receives at the same time • By late 1990s, most 100BaseT cards could auto-negotiate for full-duplex • NIC and hub/switch determine full-or-half duplex • Setting can be forced through the operating system

  19. Figure 5.4 Half-duplex; sending at the top, receiving at the bottom

  20. Figure 5.5 Full-duplex

  21. Figure 5.6 Forcing speed and duplex in Windows Vista

  22. Gigabit Ethernet

  23. IEEE 802.3ab called 1000BaseT • Most dominant Gigabit Ethernet • Four-pair UTP • Maximum cable length 100 meters • Connectors and ports look exactly like 10BaseT, 100BaseT

  24. IEEE 802.3z known as 1000BaseX • 1000BaseCX • Twinaxial cable • Shielded 150-Ohm • Maximum length of 25 meters • This standard made little progress

  25. Figure 5.7 Twinaxial cable

  26. IEEE 802.3z (continued) • 1000BaseSX • More common • Multimode fiber-optic cable • Maximum cable length 200 to 500 meters, depending on manufacturer • Uses 850-nm wavelength LED • Devices look exactly like 100BaseFX products • SC is the most common type of connection

  27. IEEE 802.3z (continued) • 1000BaseLX • Long distance carrier • Single-mode (laser) cables • Maximum cable length 5 kilometers • Special repeaters increase distance to 70 kilometers! • Positioned as the Ethernet backbone of the future • Connectors look like 100BaseSX connectors

  28. New Fiber Connectors • Problems with ST and SC connectors • ST connectors are large, twist-on • Installer must twist cable—danger of fracturing fibers • Techs have trouble getting fingers around closely packed connectors • SC connectors snap in and out, but are also large • Manufacturers wanted smaller connectors for more ports

  29. New Fiber Connectors (continued) • Solution: Small Form Factor (SFF) connectors • Mechanical Transfer Registered Jack (MT-RJ) • Local Connector (LC) • Very popular • Considered the predominant fiber connector • Other fiber connectors exist • Only standards are ST and SC • Manufacturers have different connectors

  30. Figure 5.8 MT-RJ connector

  31. Figure 5.9 LC-type connector

  32. Table 5.1 Gigabit Ethernet Summary Standard Cabling Cable Details Connectors Length 1000BaseCX Copper Twinax Twinax 25 m 1000BaseSX Multimode 850 nm Variable – 220 – 500 m fiber SC is common 1000BaseLX Single- 1,300 nm Variable – 5 km mode fiber LC, SC are common 1000BaseT CAT 5e/6 Four-pair / RJ-45 100 m UTP full-duplex

  33. 10-Gigabit Ethernet

  34. Introduction to 10-Gigabit Ethernet (10-GbE) • Showing up in high-level LANs • Expected to trickle down to the desktops in near future • New technology • Large number of fiber standards • Two copper standards • 10-GbE copper product available only since 2008

  35. Fiber-base 10-GbE • IEEE challenge • Maintain the integrity of Ethernet frame • How to transfer frames at high speeds • Could use traditional Ethernet Physical layer mechanisms • Already a usable ~10 GbE fiber network (SONET) used for WANs

  36. Fiber-base 10 GbE (continued) • IEEE Actions • A set of 10GbE standards using traditional LAN Physical-layer mechanisms • A set of 10 GbE standards using SONET infrastructure over WAN fiber • Recognized need for different networking situations

  37. IEEE created several standards defined by • The type of fiber used • The wavelength of the laser or lasers • The Physical layer signaling type • Maximum signal distance (defined by previous factors)

  38. Naming convention begins with 10GBasexy • x = type of fiber (usually) and the signal wavelength • y = Physical layer signaling standard • R for LAN-based signaling • W for SONET/WAN-based signaling

  39. 10GBaseSy uses a short-wavelength (850 nm) signal over multimode Fiber-based 10GBaseSy Summary

  40. Figure 5.10 A 10GBaseSR NIC (photo courtesy of Intel Corporation)

  41. 10GBaseLy uses a long-wavelength (1310 nm) signal over single-mode Fiber-based 10GBaseLy Summary

  42. 10GBaseEy uses an extra-long-wave-length (1550 nm) signal over single-mode fiber Fiber-based 10GBaseEy Summary

  43. 10 GbE connectors • Standards do not define the type of connector • Manufacturers determine connectors

  44. Copper-based 10GbE (10GBaseT) • 2006: IEEE standard for 10GbE running on UTP • Looks and works like slower versions of UTP Ethernet • Downside: 10GBaseT running on CAT 6 has maximum cable length of only 55 meters • 10GBaseT running on CAT 6a can to go to 100 meters

  45. Table 5.2 10-GbE Summary Wavelength / Standard Cabling Cable Details Connectors Length 10GBaseSR Multimode 850 nm Not defined 26 – 300 m /SW fiber 10GBaseLR Single- 1310 nm Variable – LC 10 km /LW mode fiber is common 10GBaseER Single- 1550 nm Variable – LC, 40 km mode fiber SC are common 10GBaseT CAT 6/6a Four-pair / RJ-45 55 – 100 m UTP full-duplex

  46. 10-GbE Physical Connections • Hodgepodge of 10-GbE types • Problem: single router may need to support several connector types • Solution: multisource agreement (MSA) • Modular transceiver plugs into10-GbE equipment • Converts between media types • Many competing media types recently • 10-GbE equipment exclusive domain of high-bandwidth LANs and WANs, including the Internet

  47. Figure 5.11 XENPAK MSA

  48. Backbones • Multispeed network works best for many situations • Series of high-speed switches create a backbone • No computers (except maybe servers) on the backbone • Each floor has its own switch connecting to every node on floor • Each floor switch has a separate high-speed connection to a main switch

  49. Figure 5.12 Typical network configuration showing backbone

  50. Figure 5.13 Switches with dedicated, high-speed add-on ports

More Related