Introduction to Computer Networks and Cybersecurity (Hardback) book cover

Introduction to Computer Networks and Cybersecurity

By Chwan-Hwa (John) Wu, J. David Irwin

© 2013 – CRC Press

1,336 pages | 1136 B/W Illus.

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Hardback: 9781466572133
pub: 2013-02-04
eBook (VitalSource) : 9781498760133
pub: 2015-09-15
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If a network is not secure, how valuable is it? Introduction to Computer Networks and Cybersecurity takes an integrated approach to networking and cybersecurity, highlighting the interconnections so that you quickly understand the complex design issues in modern networks. This full-color book uses a wealth of examples and illustrations to effectively connect the principles of networks and networking protocols with the relevant cybersecurity issues.

Get the Fundamentals of Internet Architecture and the Protocol Layers

Organized into six parts, the book walks you through the fundamentals, starting with the way most people first encounter computer networks—through the Internet architecture. Part 1 covers the most important Internet applications and the methods used to develop them. Part 2 discusses the network edge, consisting of hosts, access networks, LANs, and the physical media used with the physical and link layers. Part 3 explores the network core, including packet/circuit switches, routers, and the Internet backbone, and Part 4 examines reliable transport and the management of network congestion.

Learn about Malware and Security Systems

Building on the concepts and principles, the book then delves into state-of-the-art cybersecurity mechanisms in Part 5. It reviews the types of malware and the various security systems, made up of firewalls, intrusion detection systems, and other components. Crucially, it provides a seamless view of an information infrastructure in which security capabilities are built in rather than treated as an add-on feature. The book closes with a look at emerging technologies, including virtualization and data center and cloud computing unified communication.

Understand Cyber Attacks—and What You Can Do to Defend against Them

This comprehensive text supplies a carefully designed introduction to both the fundamentals of networks and the latest advances in Internet security. Addressing cybersecurity from an Internet perspective, it prepares you to better understand the motivation and methods of cyber attacks and what you can do to protect the networks and the applications that run on them.

Pedagogical Features

The book’s modular design offers exceptional flexibility, whether you want to use it for quick reference, self-study, or a wide variety of one- or two-semester courses in computer networks, cybersecurity, or a hybrid of both. Learning goals in each chapter show you what you can expect to learn, and end-of-chapter problems and questions test your understanding. Throughout, the book uses real-world examples and extensive illustrations and screen captures to explain complicated concepts simply and clearly. Ancillary materials, including PowerPoint® animations, are available to instructors with qualifying course adoption.


"Introduction to Computer Networks and Cybersecurity is much more than an introductory book. … It is a well written, organized, and comprehensive book regarding the security in the Internet. The authors present analytically a useful manual concerning wireless security, malware defense, and the applications in Web security. The book helps readers to follow their own paths of learning while it is structured in distinctive modules that allow for flexible reading. It is a well-informed, revised, and comprehensible educational book that addresses not only professionals but also students or anybody else interested in cyber security and needs an integrated source."

—Nicolas Sklavos, Information Security Journal: A Global Perspective (April 2014)

"This book touches every corner of the topic of computer network and cybersecurity. It explains thoroughly the concept of network layers. There are detailed instructions and illustrations on the design of each network layer employing the newest Cisco technology. In addition, the book discusses the security issues in the context of computer networks. Then it presents different prevention algorithms and techniques, starting with cryptographic techniques. Firewalls, intrusion detection/prevention systems, authentication using hash, secure socket layer, virtual private network, and wireless network security are some of the security topics, which are described with real-life scenarios. The strength of the book lies in the fact that it also includes the recent and emerging Internet Engineering Task Force and Institute of Electrical and Electronic Engineers standards and drafts that govern computer network and security technologies. Both the Instructor and the students would be able to maintain an up-to-date knowledge on the state-of-the-art technologies regarding network security. … The text book presents a comprehensive overview of the fundamental concepts as well as state-of-the-art technologies in computer networks and security in cyber domain. The modular structure of the book makes it easy to adapt it for a variety of programs, including computer engineering, computer science, computer networks, computer security, and security systems, with different student backgrounds."

—Nazrul Islam, Farmingdale State College, New York, USA, Journal of Applied Security Research (January 2014)

"This book represents one of the most comprehensive overviews of computer security I have seen recently. The reader can quickly identify and learn about various cyber attacks, and become familiar with terminology of attacks, authentication, and protocols (chain of trust, phishing attacks, cross-site request forgery attacks, bonnet attacks, DNSSEC, DKIM, SNMP, …). … The coupling of networking protocols and networks with their corresponding cybersecurity issues is a very good idea."

—Milos Manic, University of Idaho, Idaho Falls, USA

"This book combines good technical details with higher-level insights designed to help the reader focus on the right things and to understand them sufficiently. … an up-to-date and well-written book on an exciting area of computing that forms the foundation for our modern, connected lives."

—Tim Watson, Cyber Security Centre, De Montfort University, Leicester, UK

"This book is an invaluable resource for students at all levels interested in computer cybersecurity. It also serves as an excellent reference in cybersecurity for professionals in this fast-evolving and critical field. This is an excellent text, content is very refreshing, informative, and easy to follow for students ranging from novice to advanced levels. It contains an impressive collection of up-to-date cybersecurity issues and analysis."

—Simon Y. Foo, Florida State University, Tallahassee, USA

"… this book offers a full and comprehensive view of the state of the art on computer networks and cyber security issues and could serve as a sort of handbook for this area by providing clear and detailed explanations of the related various topics."

—Huijun Gao, Institute of Intelligent Control and Systems, Harbin Institute of Technology, China

"Easy-to-read, current and very well-written text."

—Jayantha Herath, St. Cloud State University, Minnesota, USA

"One cannot deal with cybersecurity without being familiar with networking (and systems and programming for that matter) but I cannot remember seeing them in the same book, especially treated at that level of detail."

—Phil Janson, EPFL (Swiss Federal Institute of Technology, Lausanne), Switzerland

"Every chapter presents its own goals, giving the students the proper perspective. Identifying learning goals is the first step to proper learning. … [This book] makes cybersecurity a concrete object that students can touch and feel, rather than just an abstract concept."

—Alptekin Küpçü, Koç University, Istanbul, Turkey

"This book by Wu and Irwin is one-stop shopping for a book that covers introduction to computer networks and to network security. Based on their industrial experience the authors selected the most important topics of both areas and created a text that can be used to learn about issues of network security while catching up on necessary details of computer networks."

—Aleksander Malinowski, Bradley University, Peoria, Illinois, USA

"I will recommend this book to any one that seeks to have in-depth knowledge in network security."

—Inah Omoronyia, School of Computing Science, University of Glasgow, Scotland, UK

"A very flexible textbook, suitable for a number of different types of lectures."

—Peter Palensky, Austrian Institute of Technology, Vienna

"This book provides valuable details of many key network protocols and algorithms that help the readers gain insight quickly. … Examples and homework problems given in the book are highly valuable, considerably beneficial for the readers to better understand the materials covered."

—Nian-Feng Tzeng, University of Louisiana, Lafayette, USA

"This is an excellent book to teach a course on network security. … The material will prepare the students for exercising better protection in terms of understanding the motivation of the attackers and how to deal with and mitigate the situation."

—Shambhu Upadhyaya, University at Buffalo, The State University of New York, USA

"This is a fantastic and practical book that provides great introduction to computer networking technology and comprehensive treatment of cybersecurity. The scope of the book covers the technology widely used in today’s computers, Internet, and servers through practical examples. The book provides important insights into how to enjoy a better and secure Internet life–it is a must read."

—Maria C. Yuang, National Chiao Tung University, Hsinchu, Taiwan

"Chapters dealing with cybersecurity are solidly rooted in modern computer networking technologies and are well situated in real interconnection scenarios. … Concepts are introduced with a clear language and progressively explained with a satisfactory degree of accuracy without exceeding in formalism. This enables understanding cybersecurity principles with small effort and makes the book suitable also to readers with little or no specific background in this area. … The coverage of topics is very comprehensive and well balanced to satisfy a large number of teaching and learning requirements through different possible selections of parts of the material presented."

—Adriano Valenzano, CNR-IEIIT National Research Council, Italy

"It gives a complete treatment of the critical important field of computer networks and cybersecurity in a clear and methodical manner. … The learning features are comprehensive, including the learning goals for each chapter, extensive examples to illustrate fundamental principles, numerous diagrams and illustrations to enhance the presentation, and a large number of end-of-chapter problems and questions to evaluate the student’s understanding of the chapters’ content."

—Gerhard P. Hancke, University of Pretoria, South Africa

"This is the main strength of the book—it is specifically designed to be helpful to teach courses on networks and its security. It is student-oriented as well as instructor-oriented—it makes the job of learning and teaching easier to the both sides."

—Wojciech Mazurczyk, Warsaw University of Technology, Poland

"… stands out as a different book. … This book can be adopted as a primary textbook for the undergraduate and the graduate classes in computer security. Even professionals working in the networking and security domain will find this book as an invaluable reference material. The strength of this book is its complete coverage of various layers of network layers from a security point of view."

—Professor Tony Thomas, Ph.D., Indian Institute of Information Technology and Management, Kerala, India

"The authors seem to have struck the right balance between technical detail and descriptiveness. Without glossing over the operational aspects of the multitude of architectures and protocols they discuss, the authors manage to retain the holistic picture across all the communication-oriented layers of the ISO OSI Model. Numerous elaborate examples illustrate new concepts immediately after they are introduced, and guide the reader almost by hand in understanding ‘how stuff works’. Inclusion of wireless and mobile networking, network virtualization and cybersecurity makes the book truly state of the art. The last part that deals with cybersecurity is especially exciting and documents the authors' vast knowledge of information security, communication protocols and application-level programming alike."

—Jerzy Konorski, Gdansk University of Technology, Poland

"To do something in the real world of networks, you need to understand the protocols in bit-by-bit, byte-by-byte level of details, as done in this book. I would also encourage my graduate students to read this book, since following through the book can guide the students to easily understand the networking protocols in a straightforward way as a software engineer and also as a network designer."

—Lynn Choi, Korea University, Seoul, Korea

Table of Contents

An Introduction to Information Networks


The Internet Architecture

Access Networks

The Network Core

Circuit Switching vs. Packet Switching

Packet Switching Delays and Congestion

The Protocol Stack

Providing the Benefits of Circuit Switching to Packet Switching

Cyber Security

History of the Internet

Concluding Remarks




The Application Layer


Client/Server and Peer-to-Peer Architectures

Inter-process Communication through the Internet


Transport Layer Services

The Hypertext Transfer Protocol (http)

Cookies: Providing States to HTTP

The Design of Efficient Information Delivery through Use of a Proxy

The File Transfer Protocol (FTP)

Electronic Mail

Concluding Remarks



DNS and Active Directory

The Domain Name Service (DNS)

Active Directory (AD)

Concluding Remarks



XML-Based Web Services

Overview of XML-Based Web Applications

Client/Server Web Application Development

The PHP Server Script



XML Schema

The XML Document Object Model (DOM)

Concluding Remarks



Socket Programming


Socket Concepts

TCP Socket Programming

Single-Thread TCP Socket Programming

Multi-thread TCP Socket Programming

UDP Socket Programming

Multi-thread UDP Socket Programming

IPv6 Socket Programming

Concluding Remarks



Peer-to-Peer (P2P) Networks and Applications


Types of P2P Networks

Pure P2P: Gnutella Networks

Partially Centralized Architectures

Hybrid Decentralized (or Centralized) P2P

Structured vs. Unstructured P2P


P2P Client Software

Peer-to-Peer Name Resolution (PNRP)

Apple’s Bonjour

Wi-Fi Direct Devices and P2P Technology

P2P Security

Internet Relay Chat (IRC)

Concluding Remarks




The Data Link Layer and Physical Layer

The Physical Layer

Link Layer Functions

Link Layer Realization

Multiple Access Protocols

The Link Layer Address

MAC Layer Frame Format

The 802.2 Logic Link Control (LLC) Sublayer

Loop Prevention and Multipathing

Error Detection

Concluding Remarks



The Ethernet and Switches

Ethernet Overview

The 802.3 Medium Access Control and Physical Layers

The Ethernet Carrier Sense Multiple Access/Collision Detection Algorithm

Ethernet Hubs

Minimum Ethernet Frame Length

Ethernet Cables and Connectors

Gigabit Ethernet and Beyond

Bridges and Switches

A Layer 2 (L2) Switch and Layer 3 (L3) Switch/Router

Design Issues in Network Processors (NPs) and ASICs

Design Issues for the Packet Buffer/Memory and Switch Fabric

Cut-Through or Store-and-Forward Ethernet for Low-Latency Switching

Switch Management

Concluding Remarks



Virtual LAN, Class of Service, and Multilayer Networks

The Virtual LAN (VLAN-802.11q)

Class of Service (CoS-802.11p)

Switch Design Issues in CoS, Queues and Switch Fabric

Asynchronous Transfer Mode (ATM)

Classical IP over ATM

Multiprotocol Label Switching (MPLS)

Multilayer Network (MLN) Architectures

Concluding Remarks



Wireless and Mobile Networks

An Overview of Wireless Networks

802.11 Wireless LANs

Wireless Personal Area Network (WPAN)

WLANs and WPANs Comparison

WiMAX (802.16)

Cellular Networks

Concluding Remarks




The Network Layer

Network Layer Overview

Connection-Oriented Networks

Connectionless Datagram Forwarding

Datagram Networks vs. Virtual Circuit ATM Networks

Network Layer Functions in the Protocol Stack

The IPv4 Header

IP Datagram Fragmentation/Reassembly

Type of Service (ToS)

The IPv4 Address

The Dynamic Host Configuration Protocol (DHCP)

IP Multicast

Routing between LANs

Multiprotocol Label Switching (MPLS)

Network Address Translation (NAT)

The Internet Control Message Protocol (ICMP)

The Mobile Internet Protocol

Concluding Remarks




The Need for IPv6

The IPv6 Packet Format

IPv6 Addresses

The Transition from IPv4 to IPv6

IPv6 Configuration and Testing

Concluding Remarks



Routing and Interior Gateways

Routing Protocol Overview

Configuring a Router

VLAN Routing

Open Shortest Path First (OSPF)

The OSPF Routing Algorithm

The Routing Information Protocol (RIP)


Concluding Remarks



Border Gateway Routing

Autonomous Systems

Border Gateway Protocol (BGP) Overview

A Real-World BGP Case

BGP Route Advertisements

BGP Route Selection

BGP Import and Export Policies

BGP Security

Concluding Remarks




The Transport Layer

Transport Layer Overview

The Socket

The User Datagram Protocol (UDP)

A Reliable Transport Protocol: TCP

The TCP Packet Header and Options

The Buffer and Sliding Window

Features of the Stream Control Transmission Protocol (SCTP)

The SCTP Packet Format

SCTP Association Establishment


SCTP Multi-Homing

Concluding Remarks



Packet Loss Recovery

Packet Acknowledgment (ACK) and Retransmission

Round Trip Time and Retransmission Timeout

Cumulative ACK and Duplicate ACK

The Sliding Window and Cumulative ACK

Delayed ACK

Fast Retransmit

Lost Synchronization (SYN) Packet and Recovery

The Silly Window Syndrome/Solution

The TCP Selective Acknowledgment (SACK) Option

Concluding Remarks



TCP Congestion Control

TCP Flow Control

TCP Congestion Control

Standard TCP End-to-end Congestion Control Methods

TCP Tahoe and TCP Reno in Request for Comment (RFC) 2001

An Improvement for the Reno algorithm—RFC 2581 and RFC 5681

TCP NewReno

TCP Throughput for a Real-World Download in Microsoft’s Windows XP

A Selective Acknowledgment (SACK)-Based Loss Recovery Algorithm

High-Speed TCP (HSTCP) Congestion Control Design Issues


Loss-Based TCP End-to-End Congestion Control Summary

Delay-Based Congestion Control Algorithms

Compound TCP (CTCP)

The Adaptive Receive Window Size

TCP Explicit Congestion Control and Its Design Issues

The Absence of Congestion Control in UDP and TCP Compatibility

Concluding Remarks




Cyber Security Overview


Security from a Global Perspective

Trends in the Types of Attacks and Malware

The Types of Malware

Vulnerability Naming Schemes and Security Configuration Settings

Obfuscation and Mutations in Malware

The Attacker’s Motivation and Tactics

Zero-Day Vulnerabilities

Attacks on the Power Grid and Utility Networks

Network and Information Infrastructure Defense Overview

Concluding Remarks





Unified Threat Management


Stateless Packet Filtering

Stateful/Session Filtering

Application-Level Gateways

Circuit-Level Gateways

A Comparison of Four Types of Firewalls

The Architecture for a Primary-Backup Firewall

The Windows 7/Vista Firewall as a Personal Firewall

The Cisco Firewall as an Enterprise Firewall

The Small Office/Home Office Firewall

Emerging Firewall Technology

Concluding Remarks



Intrusion Detection/Prevention System


The Approaches Used for IDS/IPS

Network-Based IDS/IPS

Host-Based IDS/IPS


The Detection of Polymorphic/Metamorphic Worms

Distributed Intrusion Detection Systems and Standards


The TippingPoint IPS

The McAfee Approach to IPS

The Security Community’s Collective Approach to IDS/IPS

Concluding Remarks



Hash and Authentication

Authentication Overview

Hash Functions

The Hash Message Authentication Code (HMAC)

Password-Based Authentication

The Password-Based Encryption Standard

The Automated Password Generator Standard

Password-Based Security Protocols

The One-Time Password and Token

Open Identification (OpenID) and Open Authorization (OAuth)

Concluding Remarks



Symmetric Key Ciphers and Wireless LAN Security

Block Ciphers

Stream Ciphers

The US Government’s Cryptography Module Standards

Side Channel Attacks and the Defensive Mechanisms

Concluding Remarks



Public Key Cryptography, Infrastructure and Certificates


The Digital Signature Concept

Public Key Cryptography Characteristics

Elliptic Curve Cryptography (ECC)

Certificates and the Public Key Infrastructure

Public Key Cryptography Standards (PKCS)

X.509 certificate and Private Key File Formats

U.S. Government Standards

Attacks Which Target the Public Key Infrastructure and Certificates

Email Security

Concluding Remarks



Secure Socket Layer/Transport Layer Security (SSL/TLS) Protocols for Transport Layer Security

Introductory Overview

The Handshake Protocol

Attacks on the Handshake Protocol

The Record Protocol

SSL/TLS Cryptography

Datagram Transport Layer Security (DTLS)

US Government Recommendations

Extended Validation SSL (EV-SSL)

Establishing a Certificate Authority (CA)

Web Server’s Certificate Setup and Client Computer Configuration

A Certificate Authority’s Self-Signed Root Certificate

Browser Security Configurations

Concluding Remarks



Virtual Private Networks for Network Layer Security

Network Security Overview

Internet Protocol Security (IPsec)

The Internet Key Exchange (IKE)

Data Link Layer VPN Protocols

VPN Configuration Procedure Examples

Concluding Remarks



Network Access Control and Wireless Network Security

An Overview of Network Access Control (NAC)


The Trusted Platform Module (TPM)

Multiple Factor Authentications: Cryptographic Tokens and TPM


Enterprise Wireless Network Security Protocols

Concluding Remarks



Cyber Threats and Their Defense

Domain Name System (DNS) Protection

Router Security

Spam/Email Defensive Measures

Phishing Defensive Measures

Web-Based Attacks

Database Defensive Measures

Botnet Attacks and Applicable Defensive Techniques

Concluding Remarks




Network and Information Infrastructure Virtualization

Virtualization Overview

The Virtualization Architecture

Virtual Machine Monitor (VMM) Architecture Options

CPU Virtualization Techniques

Memory Virtualization

I/O Virtualization

Server Virtualization

Virtual Networking

Data Center Virtualization

Cloud Computing

Concluding Remarks



Unified Communications and Multimedia Protocols

Unified Communications (UC)/Unified Messaging (UM)

Internet Protocol Telephony and Public Service Telephone Network Integration

Implementations of Unified Communications

The Session Initiation Protocol (SIP)

The SIP Distributed Architecture

Intelligence in Unified Communications

The Media in a Session Initiation Protocol Session

The Real-Time Protocol (RTP) and Its Packet Format

The Real-Time Control Protocol (RTCP) and Quality of Service (QoS)

Integrated Services in the Internet

The Real-Time Streaming Protocol (RTSP)

Unified Communication/Unified Messaging Security

Concluding Remarks



Glossary of Acronyms


About the Authors

Chwan-Hwa "John" Wu joined the faculty of Auburn University, Alabama, in 1987, and is currently a professor of electrical and computer engineering. He has been the principal investigator on research projects funded by NSF, the U.S. Army, NASA, USDA, and many companies, including Northrop Grumman and Lockheed Martin. His current research interests include cybersecurity. He is an author and co-author of two books, 58 journal papers, and more than 130 conference publications. He also holds five U.S. patents. Dr. Wu is a Fellow of the IEEE.

J. David Irwin joined Auburn University, Alabama, in 1969, and is currently the Earle C. Williams Eminent Scholar in the Electrical and Computer Engineering Department. He is the author or co-author of numerous publications, including 17 textbooks. He has held numerous positions within the IEEE, including president of both the Industrial Electronics and Education Societies, as well as editor-in-chief of the IEEE Transactions on Industrial Electronics. He is a Life Fellow of the IEEE and a Fellow of both the ASEE and the AAAS. He is the recipient of numerous education and technical awards.

Subject Categories

BISAC Subject Codes/Headings:
COMPUTERS / Information Technology
COMPUTERS / Networking / General
COMPUTERS / Security / General