The growth of the Internet is fundamentally reshaping communications and proving that too much bandwidth is not enough. According to communications research firm RHK Inc. of South San Francisco, the explosive growth of Internet Protocol traffic creates the prospect of a public network with 30 times the current traffic -- in just four years. This demand will be driven by increased access to high-speed Internet connections by consumers and businesses, increased Internet access outside of the US and other technologies enabling fast and cheap access. While the demand for bandwidth creates opportunities for service providers, it also creates a need for them to reduce network costs. The future network carrying 30 times today's traffic cannot cost 30 times more than today's network. Optical amplification and wavelength division multiplexing have enabled communications systems to meet bandwidth requirements and save money by using optical elements, rather than electrical elements, wherever possible. A key question facing designers of dense wavelength division multiplex (DWDM) systems is how to continue to reduce network costs...