tailieunhanh - Network+ Certification (Outline) - Chapter 5: Data-link layer protocols

Chapter summary: Supports multiple cable types and speeds, uses the CSMA/CD MAC mechanism to detect collisions, uses a logical ring topology, uses the token passing MAC mechanism, uses a double ring or star topology, uses the token passing MAC mechanism, runs at speeds up to 11 Mbps, uses the CSMA/CA MAC mechanism. | 1 Chapter 5 Data-Link Layer Protocols Chapter Overview A. B. C. D. Ethernet Token Ring FDDI Wireless Networking Chapter 5 Lesson 1 Ethernet 2 1. Ethernet Standards A. B. Ethernet is the most popular LAN protocol operating at the data-link layer. There are two sets of Ethernet standards 1. 2. DIX Ethernet the original Ethernet protocol 1. DIX Ethernet Institute of Electrical and Electronic Engineers IEEE 3 C. 4 D. Developed by Digital Intel and Xerox a. Known as thick Ethernet ThickNet or 10Base5 Privately held standard DIX Ethernet II a. Retains thick Ethernet 10Base5 b. Adds thin Ethernet 10Base2 The frame contains an Ethertype field that identifies the network layer protocol that generated the data in each packet. a. Ethertype is the only element of the DIX Ethernet standard that is still commonly used. IEEE 1. 2. 3. 4. 5. 6. 2. 3. 4. 5 E. F. G. Developed by the IEEE Retains 10Base5 and 10Base2 Added 10Base-T to the existing physical standards Not privately held It cannot legally use the name Ethernet. Virtually all implementations called Ethernet today are actually IEEE . Differences from DIX Ethernet a. IEEE has additional physical layer standards. b. Slight frame format differences IEEE 1. Fast Ethernet IEEE and IEEE 1. Gigabit Ethernet DIX Ethernet IEEE components 7. 6 7 8 9 10 11 12 13 14 2 1. Physical layer specifications 2. Frame format 3. Carrier Sense Multiple Access with Collision Detection CSMA CD Media Access Control MAC mechanism 2. Ethernet Types A. Standard 10-Mbps Ethernet B. Fast Ethernet 100 Mbps C. Gigabit Ethernet 1 000 Mbps 3. Physical Layer Specifications A. Coaxial Ethernet standards 1. 10Base5 thick Ethernet 2. 10Base2 thin Ethernet B. Coaxial network characteristics 1. Runs at 10 Mbps 2. Uses the bus topology 3. Uses mixing segments cable segments that connect more than two computers 4. 10Base5 a. Also called thick Ethernet or ThickNet b. Uses RG-8 coaxial cable c. 500-meter maximum .