rform strategic planning assumes that the carrier will penetrate the top 7,000 buildings (100 in year 1, 900 more in year 2, and so on) and will achieve an average of 3 broadband Chapter 5 customers per building. This conservative financial approach to the matter fits well with the result of this table. 18. This is based on the order flow seen at a MASP. 19. As discussed in a number of places in this book, cost-effective NEs are one component of a viable broadband carrier undertaking. Other components include reduced operational and fiber spur costs. 20. This is similar to the example discussed earlier with the sol-gel approach. CHAPTER Coarse Wavelength Division Multiplexing (CWDM) Technology Chapter 6 This chapter covers coarse wavelength division multiplexing (CWDM), which appears to be a reasonably good technology for metro access applica- tions if certain extensions are developed by vendors; however, it has not yet experienced widespread use. We also cover some related technologies in this chapter. 6.1 Technology Scope In principle, CWDM can be used by metropolitan area carriers that want to keep the cost per building low, SO that they can turn a positive net bottom line. Figure 6-1 shows a simple application of the technology, although more sophisticated systems and designs are possible. 1 CWDM technology may be used effectively until either the cost of dense WDM (DWDM) remains higher than that of CWDM or the bandwidth requirement per enterprise building exceeds 10, 40, or 320 Gbps. We discussed in Chapter 1, "Advances and Opportunities in Next-Generation SONET and Other Optical Archi- tectures," that a typical 16,000-square-foot office building in the United States currently needs about 10 Mbps and will need about 73 Mbps by Figure 6-1 Example of a simple Office Office application of Building A Building B CWDM. Data Center Switch Switch Switches 00000 10000 Office Building C Switch CWDM optical networking technology makes it possible for network switch manufacturers to easily upgrade their current Ethernet