r to take the author's proposal and adjust it to the inter- nal organizational format, present it at a formal meeting, and defend its viability. This obviously requires a considerable amount of effort, and once again I am indebted to Marjorie Spencer for shepherding my pro- posal into a contract. Copyright 2001 The McGraw-Hill Companies, Inc. Click Here for Terms of Use. Acknowledgments As a manuscript moves into the production process, it passes through the hands of copyeditors, illustrators, cover and backcopy designers, and other specialists whom I would like to collectively thank. Last but cer- tainly not least, I would like to thank my wife, Beverly, for her patience and understanding during the long nights and lost weekends while I worked researching and writing this book. CHAPTER Introduction Chapter One Imagine working in an environment where you can dynamically obtain extra bandwidth to satisfy different operational requirements. Suppose it is 8:00 A.M. on a Tuesday after a long weekend. As workers arrive and dis- cuss their weekend activities, your organization's requirement for band- width may be minimal. As the week progresses, the activity of your organization increases. Customers call in seeking support, employees access a variety of remote databases, and your organization's bandwidth requirements increase. The current bandwidth requirements of organizations are satisfied through the use of a fixed capacity local loop line linking organization- al locations to each other or to different networks. Even when capacity to a degree appears variable, such as when using Frame Relay where it is possible to burst above your committed information rate (CIR), you can burst only up to the fixed line operating rate. Now imagine the use of communications lines connecting each organizational location to a net- work where each local loop line has such a large-in fact, virtually unlimited-transmission capacity. As your organizational requirements grow and you need more bandwidth, the transmission capacity of the lin