Though some mathematical tools are used in this book, the contents described are those relating to my empirical study of teletraffic modeling and simulation. Besides, record length that is a fundamental issue in data processing and measurement of teletraffic, statistical detection of denial-of- service flood attacking, which is a hot topic in computer science, are also discussed. Although there are some theoretical results published recently, this book may yet be meaningful for engineers and graduates in the field of teletraffic engineering to comprehend how teletraffic modeling in my research evolves from the exactly self-similar process, that is, fractional Gaussian noise with the single Hurst parameter, to the current model of the generalized Cauchy process with the fractal dimension and the Hurst parameter decoupling. It is my belief that the book in methodology may also serve as a reference for random data modeling in other fields in addition to computer networks.