n algorithms to thermal and mechanical modeling adopted in the design of telecommunica- tion equipment platforms. The network is present almost everywhere in the world, allowing seamless communica- tion of sounds and images through a chain of different types of equipment produced by several equipment vendors. Not only is communication carried out smoothly in normal conditions, but its quality is also monitored continuously, allowing it to survive failure of individual components and even to maintain a certain degree of functionality in case of catastrophic events like earthquakes. The aim of this book is to present the telecommunication network as a whole, adopting a practical approach that examines evidence of not only recent developments and research directions, but also engineering subjects and key market needs that are no less important in guaranteeing the network operation standard. The great attention to standardization, both in the description of standards and in the bibliography, is functional to part of this strategy. The only area not covered by this book, out of a generic discussion, is constituted by radio systems. Considering that cellular systems are part of the access area and that radio bridges are used only in emergency situations out of the access area, this mainly impacts the way in which access to the network is performed. It will be the task of a future work to carry out an analysis of the trend toward the integration of mobile and fixed access and its effects. This book starts with a market analysis of the telecommunication environment needed to individuate trends in services and equipment development. Technical advancements, thus, do not appear as mere improvements, but as answers to precise market needs. Moreover, attention is devoted throughout the book to issues such as power consump- tion and real estate, which in some practical cases are more important than engineering key performances like capacity or reach in determining the success of a product. Quantitative data are provided for al