Published by Pearson IT Certification (September 22, 2023) © 2024
William EasttomAll you need to know about defending networks, in one book
- Clearly explains concepts, terminology, challenges, tools, and skills
- Covers key security standards and models for business and government
- The perfect introduction for all network/computer security professionals and students
Welcome to today's most useful and practical introduction to defending modern networks. Drawing on decades of experience, Chuck Easttom brings together updated coverage of all the concepts, terminology, techniques, and solutions you'll need to be effective.
Easttom thoroughly introduces the core technologies of modern network security, including firewalls, intrusion-detection systems, and VPNs. Next, he shows how encryption can be used to safeguard data as it moves across networks.
You'll learn how to harden operating systems, defend against malware and network attacks, establish robust security policies, and assess network security using industry-leading standards and models. You'll also find thorough coverage of key issues such as physical security, forensics, and cyberterrorism.
Throughout, Easttom blends theory and application, helping you understand both what to do and why. In every chapter, quizzes, exercises, projects, and web resources deepen your understanding and help you use what you've learned—in the classroom and in your career.
LEARN HOW TO
- Evaluate key network risks and dangers
- Choose the right network security approach for your organization
- Anticipate and counter widespread network attacks, including those based on "social engineering"
- Successfully deploy and apply firewalls and intrusion detection systems
- Secure network communication with virtual private networks
- Protect data with cryptographic public/private key systems, digital signatures, and certificates
- Defend against malware, including ransomware, Trojan horses, and spyware
- Harden operating systems and keep their security up to date
- Define and implement security policies that reduce risk
- Explore leading security standards and models, including ISO and NIST standards
- Prepare for an investigation if your network has been attacked
- Understand the growing risks of espionage and cyberterrorism
Preface xxiii
Chapter 1: Introduction to Network Security 2
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
The Basics of a Network.. . . . . . . . . . . . . . . . . . . . . . . . . 3
Basic Network Utilities.. . . . . . . . . . . . . . . . . . . . . . . . . 11
The OSI Model.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
What Does This Mean for Security?. . . . . . . . . . . . . . . . . . . . 16
Assessing Likely Threats to the Network. . . . . . . . . . . . . . . . . . 16
Classifications of Threats.. . . . . . . . . . . . . . . . . . . . . . . . 20
Likely Attacks.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Threat Assessment.. . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Understanding Security Terminology.. . . . . . . . . . . . . . . . . . . . 26
Choosing a Network Security Approach.. . . . . . . . . . . . . . . . . . 30
Network Security and the Law.. . . . . . . . . . . . . . . . . . . . . . 32
Using Security Resources. . . . . . . . . . . . . . . . . . . . . . . . 34
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter 2: Types of Attacks 42
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Understanding Denial of Service Attacks.. . . . . . . . . . . . . . . . . . 43
Defending Against Buffer Overflow Attacks.. . . . . . . . . . . . . . . . . 63
Defending Against IP Spoofing. . . . . . . . . . . . . . . . . . . . . . 64
Defending Against Session Hijacking.. . . . . . . . . . . . . . . . . . . 66
Blocking Virus and Trojan Horse Attacks. . . . . . . . . . . . . . . . . . 66
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Chapter 3: Fundamentals of Firewalls 82
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
What Is a Firewall?. . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Implementing Firewalls.. . . . . . . . . . . . . . . . . . . . . . . . . 90
Firewall Deployment.. . . . . . . . . . . . . . . . . . . . . . . . . . 95
Selecting and Using a Firewall.. . . . . . . . . . . . . . . . . . . . . . 96
Using Proxy Servers.. . . . . . . . . . . . . . . . . . . . . . . . . . 97
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Chapter 4: Firewall Practical Applications 106
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Using Single Machine Firewalls.. . . . . . . . . . . . . . . . . . . . . 107
Windows 10 Firewall.. . . . . . . . . . . . . . . . . . . . . . . . . . 108
User Account Control.. . . . . . . . . . . . . . . . . . . . . . . . . 110
Linux Firewalls.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Using Small Office/Home Office Firewalls.. . . . . . . . . . . . . . . . . 118
Using Medium-Sized Network Firewalls.. . . . . . . . . . . . . . . . . . 121
Using Enterprise Firewalls. . . . . . . . . . . . . . . . . . . . . . . . 124
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Chapter 5: Intrusion-Detection Systems 132
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Understanding IDS Concepts.. . . . . . . . . . . . . . . . . . . . . . 133
IDS Components and Processes.. . . . . . . . . . . . . . . . . . . . . 135
SIEM.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Evasion Techniques.. . . . . . . . . . . . . . . . . . . . . . . . . . 137
Understanding and Implementing IDSs.. . . . . . . . . . . . . . . . . . 138
Understanding and Implementing Honeypots. . . . . . . . . . . . . . . . 141
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Chapter 6: Encryption Fundamentals 152
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
The History of Encryption.. . . . . . . . . . . . . . . . . . . . . . . . 153
Learning About Modern Encryption Methods.. . . . . . . . . . . . . . . . 160
Identifying Good Encryption.. . . . . . . . . . . . . . . . . . . . . . . 173
Understanding Digital Signatures and Certificates.. . . . . . . . . . . . . . 174
MAC and HMAC.. . . . . . . . . . . . . . . . . . . . . . 179
Understanding and Using Decryption.. . . . . . . . . . . . . . . . . . . 179
Cracking Passwords.. . . . . . . . . . . . . . . . . . . . . . . . . . 180
Steganography. . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
Steganalysis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Quantum Computing and Quantum Cryptography. . . . . . . . . . . . . . 186
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Endnote.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Chapter 7: Virtual Private Networks 194
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Basic VPN Technology.. . . . . . . . . . . . . . . . . . . . . . . . . 195
Using VPN Protocols for VPN Encryption.. . . . . . . . . . . . . . . . . 197
IPsec.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
SSL/TLS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Other VPN Protocols.. . . . . . . . . . . . . . . . . . . . . . . . . . 209
Implementing VPN Solutions.. . . . . . . . . . . . . . . . . . . . . . 210
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Chapter 8: Operating System Hardening 222
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Configuring Windows Properly.. . . . . . . . . . . . . . . . . . . . . . 223
Configuring Linux Properly.. . . . . . . . . . . . . . . . . . . . . . . 244
Patching the Operating System.. . . . . . . . . . . . . . . . . . . . . 245
Configuring Browsers.. . . . . . . . . . . . . . . . . . . . . . . . . 246
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Chapter 9: Defending Against Virus Attacks 260
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Understanding Virus Attacks.. . . . . . . . . . . . . . . . . . . . . . 261
Virus Scanners.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Virus Scanning Techniques. . . . . . . . . . . . . . . . . . 272
When Antivirus Causes a Problem. . . . . . . . . . . . . . . 274
Commercial Antivirus Software.. . . . . . . . . . . . . . . . 274
Antivirus Policies and Procedures.. . . . . . . . . . . . . . . . . . . . 283
Additional Methods for Defending Your System.. . . . . . . . . . . . . . . 284
What to Do If Your System Is Infected by a Virus.. . . . . . . . . . . . . . 285
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Chapter 10: Defending Against Trojan Horses and Phishing 296
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Trojan Horses.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Phishing.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Chapter 11: Security Policies 318
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
ISO 27002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Important Standards.. . . . . . . . . . . . . . . . . . . . . . . . . . 322
Defining User Policies.. . . . . . . . . . . . . . . . . . . . . . . . . 324
Defining System Administration Policies.. . . . . . . . . . . . . . . . . . 331
Defining Access Control.. . . . . . . . . . . . . . . . . . . . . . . . 336
Defining Developmental Policies.. . . . . . . . . . . . . . . . . . . . . 337
Disaster Recovery.. . . . . . . . . . . . . . . . . . . . . . . . . . . 338
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
Chapter 12: Assessing System Security 346
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Risk Assessment Concepts.. . . . . . . . . . . . . . . . . . . . . . . 347
Evaluating the Security Risk.. . . . . . . . . . . . . . . . . . . . . . . 348
Conducting the Initial Assessment. . . . . . . . . . . . . . . . . . . . 351
Probing the Network.. . . . . . . . . . . . . . . . . . . . . . . . . . 357
Vulnerabilities.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381
McCumber Cube.. . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Security Documentation.. . . . . . . . . . . . . . . . . . . . . . . . 385
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Chapter 13: Security Standards 394
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
COBIT.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
ISO Standards.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
NIST Standards.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
U.S. DoD Standards.. . . . . . . . . . . . . . . . . . . . . . . . . . 403
Using the Common Criteria.. . . . . . . . . . . . . . . . . . . . . . . 405
Using Security Models.. . . . . . . . . . . . . . . . . . . . . . . . . 407
U.S. Federal Regulations, Guidelines, and Standards.. . . . . . . . . . . . 410
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414
Chapter 14: Physical Security and Disaster Recovery 422
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Physical Security.. . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Disaster Recovery.. . . . . . . . . . . . . . . . . . . . . . . . . . . 428
Ensuring Fault Tolerance.. . . . . . . . . . . . . . . . . . . . . . . . 432
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435
Chapter 15: Techniques Used by Attackers 438
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 438
Preparing to Hack.. . . . . . . . . . . . . . . . . . . . . . . . . . . 439
The Attack Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . 453
Session Hijacking. . . . . . . . . . . . . . . . . . . . . . . . . . . 457
Wi-Fi Hacking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459
Bluetooth Hacking.. . . . . . . . . . . . . . . . . . . . . . . . . . . 459
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 462
Chapter 16: Introduction to Forensics 466
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 466
General Forensics Guidelines.. . . . . . . . . . . . . . . . . . . . . . 467
FBI Forensics Guidelines. . . . . . . . . . . . . . . . . . . . . . . . 470
Imaging a Drive.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
Finding Evidence on the PC.. . . . . . . . . . . . . . . . . . . . . . . 474
Gathering Evidence from a Cell Phone.. . . . . . . . . . . . . . . . . . 485
Forensic Tools to Use.. . . . . . . . . . . . . . . . . . . . . . . . . 491
AccessData Forensic Toolkit.. . . . . . . . . . . . . . . . . 491
EnCase.. . . . . . . . . . . . . . . . . . . . . . . . . . 492
The Sleuth Kit. . . . . . . . . . . . . . . . . . . . . . . 492
OSForensics. . . . . . . . . . . . . . . . . . . . . . . . 492
Forensic Science.. . . . . . . . . . . . . . . . . . . . . . . . . . . 493
To Certify or Not to Certify?.. . . . . . . . . . . . . . . . . . . . . . . 493
Expert Witnesses.. . . . . . . . . . . . . . . . . . . . . . . . . . . 494
Additional Types of Forensics.. . . . . . . . . . . . . . . . . . . . . . 495
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
Endnote.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
Chapter 17: Cyber Warfare and Terrorism 504
Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504
Defending Against Computer-Based Espionage. . . . . . . . . . . . . . . 505
Defending Against Computer-Based Terrorism. . . . . . . . . . . . . . . 508
Choosing Defense Strategies.. . . . . . . . . . . . . . . . . . . . . . 514
Summary.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524
Endnotes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524
Appendix A: Answers 530
Glossary 542
9780138200589, 9/1/2023