Transmission Media

Figure 7.1 Transmission medium and physical layer

Figure 7.2 Classes of transmission media

Figure 7.3 Twisted-pair cable

Twisted Pair Provide protection against cross talk(noise) One wire-signals Second wire-Ground reference

Twisting increases probability of both the wires are effected by noise.

Therefore no of twists per unit length determines the quality of cable.

Figure 7.4 UTP and STP cables

Table 7.1 Categories of unshielded twisted-pair cables

Figure 7.5 UTP connector

Coaxial cable

Categories of coaxial cables

Figure 7.10 Fiber optics: Bending of light ray