Browse Books

Reviewer: Guenter Haring

Vehicular ad hoc networks (VANETs) are becoming increasingly important specializations of the well-known mobile ad hoc networks for car-to-car and car-to-infrastructure wireless communications. Olariu and Weigle, the editors of this collection of 14 contributions, intend to present a comprehensive source of information about vehicular networks (VNs), from theory to practice. With this intention in mind, the reader would expect an introductory chapter on VNs, providing a global picture of the entire field. Such an umbrella would be an opportunity to show what parts are covered by the chapters presented and what is missing. Unfortunately, such an introduction does not exist. Most of the contributions are clustered into six sections that cover different areas of VNs. Section 1, on traffic engineering, comprises two chapters, one on traffic monitoring and one on models for traffic flow and vehicle motion. In both chapters, the relation to corresponding questions in VNs is rather poor. These chapters could also be part of a volume on vehicular transportation. Section 2, on US and European initiatives, contains two contributions that cover initiatives in these two geographic areas. Due to the character of these chapters, the information is of rather limited sustainable value, as it either covers historical information or is an overview of existing projects. Section 3, on applications, has four chapters that cover safety-related and emerging applications, as well as the use of infrastructure and content delivery in zero-infrastructure VANETs. Three of these four contributions come from the same department and most of their content relates too much to concrete existing projects, to the detriment of generalized information, including key aspects and current or future challenges. The fourth contribution, on emerging vehicular applications, is well structured and the material is presented in a very systematic way. The next section, on networking issues, has three contributions and is the best part of this volume, by far. The material on mobile ad hoc routing, delay-tolerant networks, and localization in VANETs gives a very good, systematic overview of the respective topics. On the other hand, Section 5, on simulation, is quite strange. The first chapter, on vehicular mobility models, is very well done but it does not really fit into this section. The content relates more to what is presented in Section 1. The second chapter in this section, on simulators, is a brief overview of existing VNs, mobility, networks, and tightly integrated simulators. It gives a product overview, without discussing the challenging questions that emerge in VANET simulations. The last section, on human factors, has one chapter on mental workload and driver distraction due to in-vehicle displays. This contribution contains a bit of everything, and the reader might not expect to see it as part of a volume on VNs. Furthermore, it would fit much better in the section on applications. In conclusion, I have rather mixed feelings about this volume. The intention to provide substantial information on VANETs is great, but the result is not really satisfying. The goal to address everybody is quite difficult to meet, and I do not think that this objective was reached. The quality of the contributions varies greatly and a general structure is missing. A summary containing future trends and challenges for each contribution, for example, would have been a substantial improvement. Also missing is a list of abbreviations, which is usually quite helpful in any book on communications and networking. Online Computing Reviews Service

Reviewer: Aun Haider

Vehicular ad hoc networks (VANETs) are becoming popular among vehicle manufacturers, regulatory and law enforcement agencies, academia, and research groups around the globe. Two different modes of wireless communication in a vehicular network have emerged: vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Although most of these technologies are currently in trial stages, it is logical to envision that in the future, VANETs will be widely adopted around the world. Thus, there is an urgent need to understand major issues regarding policy design, technical research, and deployment efforts. Also, some lessons can be learned from studying the state of affairs of various current VANET projects. This book aims to achieve these goals. An important aspect of the book is the easy style of writing that makes it suitable not only for specialists, but also generalists. Some parts of the book-for instance, parts of chapters 1, 5, and 14-could even be useful to the general public, for nice, scientific exposure to vehicular traffic-related issues. Some fundamental aspects of VANETs, thoroughly discussed in this book, include car-to-car and car-to-infrastructure (car-2-x) communication, and vehicle infrastructure cooperation. As mentioned in the preface, some topics overlap; instead of being a hindrance, this further expands the vision of the reader on crucial VANET topics. Overall, the book is a concise overview of the state-of-the-art technologies and important research issues related to VANETs. The material presented is divided into six sections: "Traffic Engineering" (two chapters), "U.S. and European Initiatives" (two chapters), "Applications" (four chapters), "Networking Issues" (three chapters), "Simulation" (two chapters), and "Human Factors" (one chapter). The two chapters in Section 1 are "Traffic Monitoring" and "Models for Traffic Flow and Vehicle Motion." The first chapter opens with a discussion on the causes of traffic congestion, followed by short discussions on traffic volume, vehicle classification, and formulas for traffic speed and traffic density. Next, it describes some commonly used sensor technologies and probe-based detection methods. The second chapter presents some already known mathematical models for vehicular motion. They can be used as a starting point for further research. Some simulation results for longitudinal and transversal hopping mode are also presented. Section 2 describes vehicle-infrastructure cooperation and car-2-x communication initiatives in the US and Europe. Essential aspects of various projects are nicely described. Figure 4.2 presents an overview of major European research and development projects, for a quick review. Reading the two chapters in this section can update one's knowledge of current projects for vehicular networks. Section 3 deals with safety-related vehicular applications. The first chapter in this section (chapter 5) quantitatively describes various types of safety-related messages. This insightful safety information will be of interest to people from various parts of society. Chapter 6 presents some emerging vehicular applications that use cellular networks and mobile worldwide interoperability for microwave access (WiMAX). VANET routing protocols, urban monitoring services, and sensor platform projects are also briefly discussed. Then, we move to important topics such as content distribution, live video, emergency video streaming, and the use of network coding for reliable video streaming. Video streaming over third-generation (3G) services, the virtual marketplace in VANETs, the vehicular information transfer protocol, and the use of peer-to-peer (P2P) systems are also presented, along with a few other interesting applications, such as voice chatting in vehicular social networks, online passenger games, and real-time road traffic views. The last chapter of this section describes traffic adaptive packet-relaying protocols for content delivery in zero infrastructure in VANETs. It presents a protocol named ZIPPER for P2P content delivery and its performance analysis, using simulations. Section 4 deals with networking issues, in detail. Chapter 9 thoroughly describes mobile ad hoc routing in the context of vehicular networks. Various existing protocols, such as destination-sequenced distance-vector (DSDV), optimized link state routing (OLSR), dynamic source routing (DSR), ad-hoc on-demand distance vector (AODV), dynamic MANET on-demand (DYMO), and zone routing protocol (ZRP) are explained in a way that is quite easy to understand. The material presented in this chapter is supported with a good number of references that can be used for further study. Delay-tolerant VANETs are also explained qualitatively. This section closes with a chapter on localization issues in VANETs. It discusses the use of a global positioning system (GPS) and a differential GPS in the positioning of vehicles. Section 5 deals with the use of simulations in VANETs. Chapter 12 mathematically describes vehicular mobility models; it can be studied in conjunction with chapter 2. This chapter is worth studying for people who are interested in the analytical modeling of vehicular traffic. Several simulation results are also presented. Chapter 13 gives an overview of various types of simulators available for VANET simulations. Although most of the information presented is available online, this chapter is very useful for students and new researchers, to help them select the right simulator for their work. Section 6 concludes with the human factor in vehicular networks. It discusses several physiological and psychological phenomena related to drivers, and investigates factors that can cause drivers to become distracted while driving. The subsections on high-risk drivers, novice drivers, and older drivers can be very useful for generalists. Mental workload and multiple resource theory are identified as two key theoretical constructs for driver distraction and the potential for in-vehicle systems to distract the driver. The chapter closes with a subsection on driver assistance systems. The book does have some weaknesses: several references lack page numbers; no numerical examples are provided, so the book cannot be readily used as a textbook; and some topics, such as traffic models, are covered multiple times-it would have been helpful if all similar material was either combined in one place or referenced. Online Computing Reviews Service