OSI OSI 15% 20% OSI OSI ISO International Standard Organization 1984 OSI Open-data System Interface Reference Model OSI OSI OSI OSI ISO Prototype Prot

OSI

OSI OSI 15% 20% OSI OSI ISO International Standard Organization 1984 OSI Open-data System Interface Reference Model OSI OSI OSI OSI ISO Prototype Protocol OSI OSI OSI OSI OSI O S I 2-1 Application LayerPresentation Layer Session LayerTransport LayerNetwork Layer Data Link LayerPhysical Layer 2-2

第二章 OSI 七層參考模組 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical 2-1 OSI OSI OSI All People Seem To Need Data Process All People Seem To Need Domino's Pizza OSI 1. 2. 3. 2-3

4. 5. 6. OSI 1. Layer ServicesFunctions Layer lower layer 2. Protocol Protocol agreementstandard a set of rules Protocol Protocol 2W1H What is communicated Protocol When it is communicatedhow it is communicated Protocol 3. Interface OSI Interface 4. Architecture Layers + Protocols + Interfaces = Architecture Physical Layer Physical Layer Radio Frequency Physical Layer 2-4

第二章 OSI 七層參考模組 Physical Layer bit Stream bit Physical Layer bit 0 1 Physical Layer Signals0 1 encoded decoded 2-2 1 0 A A -A Time -A Time 2-2 1 0 0 0 IEEE802.3 2-3 2-5

1 0 1 1 0 0 1 A Time - A 2-3 1 0 1 1 0 0 1 Physical Layer Synchronization PSTN Symmetric A D S L ADSL Asymmetric 1 Physical Layer Bit Error Rate, BER 2-6 1 ADSL = Asymmetric Digital Subscriber Line

第二章 OSI 七層參考模組 P h y s i c a l L a y e r H u b Repeater 2-1 Physical Layer Physical Layer 2-1 Physical Layer Signal Transport Media Interference Equipments Unit Hub Repeater Bit Data Link Layer Data Link Layer IEEE Logic Link Control Sublayer, LLC Medium Access Control Sublayer, MAC 2-4 2-7

LIC Sublayer Data Link Layer MAC Sublayer 2-4 Data Link LLC frame Logic Link Control Sublayer, LLC 2-5 LLC 2-6 MAC Medium Access Control Sublayer, MAC MAC IP IPX Apple Talk LLC Ethernet II Ethernet SNAP Ethernet 802.3 Ethernet 802.2 MAC 2-5 LLC 2-8

第二章 OSI 七層參考模組 3 2 1 Ack: 2 Error 2 5 4 Ack: well done 2-6 LLC 2-7 2-8 2-9 2-7 2-7 Ethernet 2 2 LAN 2-9

CSMA/CD CSMA/CA CSMA/CD Carrier sense multiple access with collision detection Jam CSMA/ CD CSMA/CA Carrier sense multiple access with collision avoidance Idle Idle busy busy Idle Token Passing 2-8 token token token Token Ring FDDI Polling Polling MAU 2-9 2-10

第二章 OSI 七層參考模組 Token 2-8 Token Passing MAU 2-9 Polling MAC Medium Access Control Sublayer, MAC MAC MAC MAC Address MAC MAC 2-11

Port MAC Windows DOS ipconfig/all MAC 2-10 Physical Address 00-21-5C-00-51-1D MAC 48bit 6 Vendor Code 00-21-5C Intel Vendor Code 6 Windows Linux Unix-like ifconfig 2-11 Hwaddr MAC 2-10 Windows MAC 2-12 2-11 Linux MAC

第二章 OSI 七層參考模組 MAC LAN Frame LAN Switch PC PC1 PC2 PC1 LAN Switch Switch MAC table PC2 Port PC2 Switch Cut-Through Switch PC2 Switch Store and Forward Switch PC2 Switch MAC Table MAC Address Port Port MAC Switch MAC Table Switch Switch Flood Port Switch Flood Flood Switch MAC MAC table MAC Switch Switch Flood Data Link Layer Switch Bridge Wireless Access Point AP Switch AP 2-2 Data Link Layer 2-2 Data Link Layer Data Link Layer Topology Access Addressing Unit Services Error Control Equipments Bus, Ring, Polling, Tree (Star) Contention, Token Passing, Polling MAC Address, MAC Table Frame CSMA/CD, CSMA/CA Switch, Bridge, Wireless AP 2-13