e computer industry. InP is a compound made of binary crystals produced by combining one element from the metallic Group III of the periodic table with an element from the nonmetallic Group V. InP has photonic properties that allow for the large-scale integration of components such as lasers, detectors, dynamic components, passive waveguides, and electronics onto the same chip. Its qualities make InP a good fit for circuits in wireless devices as well. Components built with InP consume very little power, permitting them to remain connected to the Internet over high-speed wireless networks for extended periods. InP's short- comings include low yields of InP wafers in manufacturing (less than 40%) and the labor-intensive effort to build optical networking equipment, which make these components expensive. Integrated optical circuits could lower costs of components by 90%. Currently, components account for as much as 50% of the cost on a long-haul US$100,000 DWDM device and 15% of the cost on a US$40,000 metro WDM system. Innova- tions in optical chip making will make possible 100Mbps network connections for homes at less than $10 per month. Optical Network Management One of the most important areas of any networking technology is network manage- ment, which in the case of optical networks involves network restoration, wave- length services, and performance. As discussed earlier in this chapter, most optical networks today are based on an existing SDH/SONET architecture. One of the great strengths of SDH/SONET is, in fact, its network restoration capabilities. However, as new elements such as WDM systems are added, it can be difficult to ensure that restoration techniques are not in conflict. At the very least, the network management system must enable the service provider to identify any possible conflicts (not to mention resolve them). Along with managing the overall network, the network management sys- tem performs some specific tasks, such as monitoring the signal performance for each wavelength. And the more ele