Preface

Complex networks are networks that have complex and irregular connectivity patterns. Unlike regular networks that have clear motifs on the organization of nodes and edges, complex networks are challenging to understand and characterize. The study of complex networks is important due to the fact that complex networks appear in many aspects of our life, including, for example, biological networks, molecular networks, social networks, transportation networks, electric power grids, communication networks, and the Internet. In fact, most physical and biological systems can behave as a complex network of subsystems and connectivity between them. Therefore, complex network modeling spans a large number of natural as well as man-made networks. Study of complex networks can in fact help in the study of many of those physical systems. Further, there has been an evolution of Big Data in the form of huge networks arising from the Internet, social, biological, and computer networks. This book is an effort toward bringing the networking, information sciences, signal processing, and statistical physics communities together.

This book provides a novel treatment on complex networks, with an engineering perspective, by focusing on communications, networking, as well as signal processing dimensions. The book is primarily intended for pedagogy at the senior undergraduate and graduate level. A secondary audience for the book includes researchers and practitioners. For classroom pedagogy, we provide a large number of examples and end-of-chapter exercises. For researchers, we have included many topics, such as a section on open research issues, in each chapter.

The book is designed to be used primarily as a classroom textbook for senior undergraduate and graduate students. To make it suitable for teaching, it contains more than 100 examples, more than 200 figures, and more than 20 comparison tables. Each chapter has a section that lists open research issues and a set of end-of-chapter exercises. Further, the book’s appendices include additional information for the following: (i) relevant basic concepts and definitions, (ii) a list of top quality research conferences, (iii) a list of research journals, (iv) a list of useful software tools available for complex network analysis, (v) complex network datasets available for research, and (vi) top research groups in complex networks from various parts of the world.

The main supplementary materials we provide are as follows: (i) solutions manual for instructors; (ii) presentation slides with LaTeX source code for each chapter; (iii) code fractions for a selected subset of figures, simulations, and examples; and (iv) in addition to the online information provided by the publisher, we provide a support website (https://complexnetworksbook.github.io) to disseminate new and relevant information about complex networks.

We would like to acknowledge our peers, colleagues, and students whose feedback helped us during the preparation of this book. We thank Prof. K. R. Ramakrishnan of Indian Institute of Science, Bangalore, India, for his help in clarifying certain aspects of graph signal processing. Our sincere thanks extend to Prof. Aleksandar Dogandžić of Iowa State University, USA, for the discussions on various topics related to signal processing on graphs. We express our thanks to Indian Institute of Space Science and Technology (IIST) faculty members Prof. Deepak Mishra, Prof. Gorthi Sai Subramanyam, and Prof. Vineeth Bala Sukumaran for their help in our research in graph signal processing and complex networks. We also would like to thank our collaborators Prof. C. Siva Ram Murthy, Prof. Ramesh Rao, Prof. Bheemarjuna Reddy Tamma, and Prof. Venkata Ramana Badarla. We would like to thank Prof. Theodore S. Rappaport for having accepted our book as part of his highly respected Prentice Hall Communications Engineering and Emerging Technologies Series. Our thanks are extended to Mr. Chetan Kumar Verma, Ms. Aditi Verma, Mr. Sarath Babu, Ms. Nivedita Gaur, Mr. Gaurav Jain, and Ms. Priti Singh. Our Acquisition Editor at Pearson Inc., Ms. Kim Boedigheimer, has helped us with all necessary support during this work. Ms. Divya R. S., our lab tutor at the Systems and Networks lab, IIST, helped in many logistics arrangements during the preparation of this textbook. We thank the IIST library, its librarian Mr. Abdunnasar, and staff of the reprographic section of IIST library for helping us with certain reprographic support during the preparation of the book.

We also thank our family members who stood by us during the preparation of the book.

We thank the Indian Institute of Space Science and Technology, Thiruvananthapuram, India, and its director, Dr. Vinay Kumar Dadhwal, for permitting us to publish this book.

We also thank the reviewers and editors at Pearson and associated organizations for their help in reviewing, editing, and publishing this textbook. In particular, we thank Angela Urquhart, Julie Nahil, and Andrea Archer for their help in producing the book on time.

This book reviews or cites more than 200 scientific works. However, it is impossible to discuss all the relevant contributions in the field of complex networks. We have made choices based on our focus and structure of this book. Our topic selection does not, by any means, imply that work not included in the book is less valuable, and we apologize, in advance, to all the researchers and students who feel that their work has been overlooked.

We have taken good care to avoid typographical errors, mistakes in figures, and other inconsistencies in the book. It is, however, still possible to have some errors remain undetected in the textbook. Kindly let us know, by email or other contact information, any errors that you may spot. Our current email addresses are provided in the following pages for our readers to contact us with any queries, comments, suggestions, or error reporting.

B. S. Manoj
Abhishek Chakraborty
Rahul Singh