t for fiber to the home to be economically justified, let's examine the one area where business is literally booming. That area is known as a bypass technology. Bypass The mention of the term bypass to a local telephone company is in many ways similar to a matador waving a red flag at a bull. The reason for the ill-will toward this term is the fact that it results in a loss of revenue to the communications carrier. There are many types of bypass operations, ranging from the manner in which a residential Fiber in the Neighborhood customer bypasses the long-distance telephone company by dialing a number using a "1010" prefix, to the apartment or office building man- ager, which permits a competitive local exchange carrier to directly connect their building to the CLEC network. In this section we will focus on the latter, as it is normally accomplished via the use of optical fiber. Figure 7.9 illustrates the relationship between cabling performed by a CLEC and an existing local exchange carrier (LEC); the latter term is used to denote the incumbent telephone company. Although the CLEC may be independently located, it can also have its office within the incumbent telephone company central office. Thus, the primary differ- ence between the two concerns the type and structure of cabling. The incumbent telephone company built their network infrastruc- ture over a period of approximately 50 to 100 years by routing copper cable directly into buildings. In comparison, a CLEC providing a bypass capability that enables subscribers to avoid the high cost of local terminations commonly constructs a fiber loop in an urban area with termination points at buildings that sign up for their services. One of the earliest firms to offer this type of service was Metropolitan fiber Figure 7.9 Comparison of Office cabling methods of Office the incumbent tele- Building phone company and a competitive local exchange carrier Legend: metallic Central CLEC competitive cable Office local exchange carrier Office Building Office Building Chapter