ven Bandwidth per Figure 1-5 Typical Building Bandwidth requirements per building as a function 70 Mbps of time. 60 Mbps 50 Mbps 40 Mbps 30 Mbps 20 Mbps 10 Mbps Chapter 1 higher numbers. According to published sources such as the Yankee Group, the market for wavelength services is expected to reach $1 billion by 2004.21 On the equipment front, in the second quarter of 2001 worldwide rev- enues for optical last-mile Customer Premises Equipment (CPE) reached $75 million, and they are expected to grow to $138 million by the second quarter of 2002, with Ethernet CPEs accounting for 18 and 37 percent of these revenues, respectively.5 According to CIR, the market opportunity for networking vendors supplying SONET, DWDM, and optical Ethernet for U.S. metro access/metro core applications could reach $2.5 billion by 2005. Market forecasts are typically optimistic; we have quoted herewith some of the best possible sources. In other sections of the book, we occasionally provide smaller forecasts based on our own assessment of the potential opportunities. It is a well-known fact that less than 5 percent of commercial buildings in the United States with more than 5,000 square feet of space have fiber connectivity (only between 21,000 and 35,000, depending on the estimate, out of the 735,000 commercial office buildings in the United States, not to mention the entire set of 4.6 million commercial buildings). 23,24 Therefore, there is a tremendous opportunity in the next 5 to 10 years to develop products that will support the eventual mandatory connectivity that all of these buildings will need to support their existence in an information/ Internet-based economy. The fiber glut of the early 2000s only existed in the long-haul environment, if at all, not in metropolitan network environments. Without any doubt, broadband penetration will grow for the rest of the decade. It is worth noting, however, that a debate was under way at the time of this writing regarding the growth of the Internet. One source summa- rized the debate as fo