1. 1 Chapter Overview Ethernet Token Ring FDDI Wireless Networking

2. 2 Ethernet Standards Ethernet is the most popular local area network (LAN) protocol operating at the data- link layer. There are two sets of Ethernet standards: DIX Ethernet Institute of Electrical and Electronic Engineers (IEEE) 802.3

3. 3 DIX Ethernet Standards DIX Ethernet. Also known as thick Ethernet, ThickNet, or 10Base5 DIX Ethernet II. Retains 10Base5 and adds 10Base2 (thin Ethernet)

4. 4 IEEE 802.3 Standards IEEE 802.3. 10Base5, 10Base2, and 10Base-T IEEE 802.3u. Fast Ethernet IEEE 802.3z and IEEE 802.3ab. Gigabit Ethernet

5. 5 DIX Ethernet/IEEE 802.3 Components Physical layer specifications Frame format CSMA/CD MAC mechanism

6. 6 Standard 10-Mbps Ethernet Specifications DesignationCable TypeTopologyMaximum Length 10Base5RG-8 coaxialBus500 meters 10Base2RG-58 coaxialBus185 meters 10Base-TCategory 3 UTPStar100 meters Fiber Optic Inter- Repeater Link (FOIRL) Multimode fiber optic Star1,000 meters 10Base-FMultimode fiber optic Star500–2,000 meters

7. 7 Fast Ethernet (100 Mbps) Specifications DesignationCable TypeTopologyMaximum Length 100Base-TXCategory 5 UTPStar100 meters 100Base-T4Category 3 UTPStar100 meters 100Base-FXMultimode fiber optic Star412 meters

8. 8 Gigabit Ethernet (1,000 Mbps) Specifications DesignationCable TypeTopologyMaximum Length 1000Base-TCategory 5 or 5E UTPStar100 meters 1000Base-LXVarious multimode fiber optic Star550–5,000 meters 1000Base-SXVarious multimode fiber optic Star220–500 meters 1000Base-LHSinglemode fiber opticStar10 kilometers 1000Base-ZXSinglemode fiber opticStar100 kilometers 1000Base-CX150-ohm copperStar25 meters

9. 9 Coaxial Ethernet Standards 10Base5 (thick Ethernet) 10Base2 (thin Ethernet)

10. 10 Coaxial Network Characteristics Runs at 10 Mbps Uses the bus topology Uses mixing segments

11. 11 Mixing Segments

12. 12 UTP Ethernet Standards 10Base-T 100Base-TX (Fast Ethernet) 100Base-T4 (Fast Ethernet) 1000Base-T (Gigabit Ethernet)

13. 13 UTP Network Characteristics Runs at various speeds up to 1,000 Mbps Uses the star topology Requires a hub Uses link segments

14. 14 Link Segments

15. 15 Fiber Optic Ethernet Fiber Optic Inter-Repeater Link (FOIRL) IEEE 802.3 fiber optic standards: 10Base-FL 10Base-FB 10Base-FP 100Base-FX Gigabit Ethernet standards

16. 16 The 5-4-3 Rule A standard network can have no more than FIVE segments, connected by FOUR repeaters, of which no more than THREE segments can be mixing segments.

17. 17 A Coaxial 5-4-3 Network

18. 18 A UTP 5-4-3 Network

19. 19 Fast Ethernet Hub Types ClassFunction IConnects different cable segment types IIConnects identical cable segment types

20. 20 Fast Ethernet Cabling Guidelines Hub Type Maximum Number of Hubs Maximum Total Cable Length (UTP) Maximum Total Cable Length (Fiber Optic) Class I1200 meters272 meters Class II2205 meters228 meters

21. 21 The Ethernet Frame Format

22. 22 Protocol Identification DIX Ethernet frames use the Ethertype field. IEEE 802.3 frames use the Logical Link Control (LLC) and Subnetwork Access Protocol (SNAP) subheaders.

23. 23 Media Access Control (MAC) Is the mechanism that enables multiple computers to use the same network medium without conflicting

24. 24 CSMA/CD Phases PhaseDescription Carrier senseA computer listens to the network before transmitting. Multiple accessWhen the network is clear, the computer transmits the packet. Collision detectionThe computer checks for signs of a collision. If one occurs, it retransmits the packet. CSMA

25. 25 Collisions Collisions are also called signal quality errors. They are normal on Ethernet networks. The frequency of collisions increases as network traffic increases. Late collisions are a sign of a serious problem. CollisionContention

26. 26 Token Ring Cable Types IBM Type 1. Proprietary shielded twisted pair (STP) (Up to 300 meters & 260 Workstations) IBM Type 3. Standard Category 5 unshielded twisted pair (UTP) (Up to 150 meters & 72 Workstations)

27. 27 IBM Type 1 Cable Lobe Cable

28. 28 Token Passing A token frame circulates continuously around the network. Only the computer holding the token can transmit data. The transmitting system is responsible for removing the data from the ring. Token PassingToken Ring Network

29. 29 Token Ring Frame Types Data frame Token frame Command frame Abort delimiter frame

30. 30 The Data Frame Format (Operates at the LLC)

31. 31 The Token Frame Format

32. 32 Fiber Distributed Data Interface (FDDI) Characteristics First commercial 100-Mbps fiber optic protocol Uses the token passing MAC mechanism Supports both: singlemode cable (600 Km segments) multimode cable (100 Km segments & 500 Workstations)

33. 33 FDDI Topologies Double ring (Wrap Ring) Logical ring Dual ring of trees

34. 34 Dual Ring of Trees

35. 35 FDDI (Fiber Distributed Data Interface) Frame Types Data frame Token frame Station Management Frame (In charge of the ring maintenance and Network diagnostics)

36. 36 The FDDI Data Frame

37. 37 Wireless Networking IEEE 802.11 Standards IEEE 802.11a. Speeds of 1 to 2 Mbps IEEE 802.11b. Speeds of 5.5 to 11 Mbps

38. 38 IEEE 802.11 Topologies Ad hoc (or Independent). Wireless computers communicating with each other Infrastructure. Wireless computers using an access point to communicate with a cabled network Wireless LANs

39. 39 IEEE 802.11 Signals Supported Direct Sequence Spread Spectrum (DSSS) Frequency Hopping Spread Spectrum (FHSS) Infrared

40. 40 CSMA/CA Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is a variation of CSMA/CD. It uses packet acknowledgment messages instead of collision detection.

41. 41 Chapter Summary Ethernet Supports multiple cable types and speeds Uses the CSMA/CD MAC mechanism to detect collisions Token Ring Uses a logical ring topology Uses the token passing MAC mechanism FDDI Uses a double ring or star topology Uses the token passing MAC mechanism Wireless Networking Runs at speeds up to 11 Mbps Uses the CSMA/CA MAC mechanism