Note Headers are added to the data at lavers 6,5,4,3,and2. Trailers are usually added only at laver 2 CSIE NTUT TANAN
CSIE, NTUT, TAIWAN 16 Headers are added to the data at layers 6, 5, 4, 3, and 2. Trailers are usually added only at layer 2
An exchange using the OSI model L7 data L7 data L7 data 6 l7 data H6 L6 data H5 L6 data H5 「L5daaH4 L5 data H4 L4 dataH3 765432 L4 data H3 L3 data L 3 data 010101010101101010000010000 0101010101011010100001000 Transmission medium Figure 2-3 CSIE, NTUT, TANAN
CSIE, NTUT, TAIWAN 17 Figure 2-3 An exchange using the OSI model
2.2 LAYERS IN THE OSI MODEL CSIE NTUT TANAN
CSIE, NTUT, TAIWAN 18 LAYERS IN THE OSI MODEL 2.2
Physical layer Coordinates the functions required to transmit a bit stream over a physical medium Concerns Physical characteristics of interfaces and medium Representation of bits Data rate(Transmission rate bits/sec Synchronization of bits CSIE NTUT TANAN
CSIE, NTUT, TAIWAN 19 Physical Layer • Coordinates the functions required to transmit a bit stream over a physical medium • Concerns – Physical characteristics of interfaces and medium – Representation of bits – Data rate (Transmission rate): bits/sec – Synchronization of bits