An obvious application for 802.11b is to provide the infamous "last mile" network service. This term refers to the stretch that sits between those who have good access to the Internet (ISPs, telcos, and cable companies) and those who want it (consumers). This sort of arrangement requires 802.11b equipment at both ends of the stretch (for example, at an ISP's site and at a consumer's home).
Unfortunately, the nature of radio communications at microwave frequencies requires line of sight for optimal performance. This means that there should be an unobstructed view between the two antennas, preferably with nothing but a valley between them. This is absolutely critical in long distance, low power applications. Radio waves penetrate many common materials, but range is significantly reduced when going through anything but air. Although increasing transmission power can help get through trees and other obstructions, simply adding amplifiers isn't always an option, as the FCC imposes strict limits on power. (See Appendix A for a copy of the FCC Part 15 rules that pertain to 2.4GHz emissions. We will return to this subject in detail in Chapter 7.)
Speaking of amplifiers, a related technical obstacle to wireless nirvana is how to deal with noise in the band. The 2.4GHz band isn't reserved for use solely by 802.11b gear. It has to share the band with many other devices, including cordless phones, wireless X-10 cameras, Bluetooth equipment, burglar alarms, and even microwave ovens! Using amplifiers to try to "blast" one's way through intervening obstacles and above the background noise is the social equivalent of turning your television up to full volume so you can hear it in your front yard (maybe also to hear it above your ringing telephone and barking dog, or even your neighbor's loud television...).
If data is going to flow freely over the air, there has to be a high degree of coordination among those who set it up. As the airwaves are a public resource, the wireless infrastructure should be built in a way that benefits the most people possible, for the lowest cost. How can 802.11b effectively connect people to each other?