and nonterrestrial facilities combined-is important because in disastrous events such as earthquakes, floods, and fires, if one alternative is completely disabled, another medium might still work. As discussed in this chapter, you can assess various parameters to determine which media type is most appropriate for a given application. This chapter focuses on the five traditional transmission media formats: twisted-pair copper used for analog voice telephony, coaxial cable, microwave and satellite in the context of traditional carrier and enterprise applications, and fiber optics. (Contemporary transmission solutions are discussed in subsequent chap- ters, including Chapter 11, "Optical Networking," and Chapter 16, "Emerging Wireless Applications.") Table 2.1 provides a quick comparison of some of the Traditional Transmission Media Table 2.1 Traditional Transmission Media Characteristics Performance: Media Type Bandwidth Typical Error Rate Twisted-pair for analog voice applications Poor to fair (10-5) Coaxial cable Good (10-7 to 10-9) Microwave 100GHz Good (10-9) Satellite 100GHz Good (10-9) Fiber 75THz Great (10-11 to 10-13) important characteristics of these five media types. Note that recent developments in broadband alternatives, including twisted-pair options such as DSL and wire- less broadband, constitute a new categorization of media. The frequency spectrum in which a medium operates directly relates to the bit rate that can be obtained with that medium. You can see in Table 2.1 that tradi- tional twisted-pair affords the lowest bandwidth (i.e., the difference between the highest and lowest frequencies supported), a maximum of 1MHz, whereas fiber optics affords the greatest bandwidth, some 75THz. Another important characteristic is a medium's susceptibility to noise and the subsequent error rate. Again, twisted-pair suffers from many impairments. Coax and fiber have fewer impairments than twisted-pair because of how the cable is constructed, and fiber suffers the least because it is not affected by electric