1. Copyright © 2002 ProsoftTraining. All rights reserved. Network Security and Firewalls

2. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 1: What Is Security

3. Objectives Define security Explain the need for network security Identify resources that need security Identify the two general security threat types List security standards and organizations

4. What Is Security? LANs WANs VPNs Network perimeters

5. Hacker Statistics One of every five Internet sites has experienced a security breach Losses due to security breaches are estimated at $10 billion each year Intrusions have increased an estimated 50 percent in the past year

6. What Is the Risk? Categorizing attacks Countering attacks systematically

7. The Myth of 100-Percent Security Security as balance Security policies

8. Attributes of an Effective Security Matrix Allows access control Easy to use Appropriate cost of ownership Flexible and scalable Superior alarming and reporting

9. What You Are Trying to Protect End user resources Network resources Server resources Information storage resources

10. Who Is the Threat? Casual attackers Determined attackers Spies

11. Security Standards Security services –Authentication –Access control –Data confidentiality –Data integrity –Nonrepudiation Security mechanisms –The Orange Book

12. Summary Define security Explain the need for network security Identify resources that need security Identify the two general security threat types List security standards and organizations

13. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 2: Elements of Security

14. Objectives Formulate the basics of an effective security policy Identify the key user authentication methods Explain the need for access control methods Describe the function of an access control list

15. Objectives (cont’d) List the three main encryption methods used in internetworking Explain the need for auditing

16. Elements of Security AuditAdministration EncryptionAccess Control User Authentication Corporate Security Policy

17. The Security Policy Classify systems Prioritize resources Assign risk factors Define acceptable and unacceptable activities Define measures to apply to resources Define education standards Assign policy administration

18. Encryption Encryption categories –Symmetric –Asymmetric –Hash Encryption strength

19. Authentication Authentication methods –Proving what you know –Showing what you have –Demonstrating who you are –Identifying where you are

20. Specific Authentication Techniques Kerberos One-time passwords

21. Access Control Access Control List –Objects Execution Control List –Sandboxing

22. Auditing Passive auditing Active auditing

23. Security Tradeoffs and Drawbacks Increased complexity Slower system response time

24. Summary Formulate the basics of an effective security policy Identify the key user authentication methods Explain the need for access control methods Describe the function of an access control list

25. Summary (cont’d) List the three main encryption methods used in internetworking Explain the need for auditing

26. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 3: Applied Encryption

27. Objectives Create a trust relationship using public-key cryptography List specific forms of symmetric, asymmetric, and hash encryption Deploy PGP in Windows 2000 and Linux

28. Creating Trust Relationships Manually Automatically

29. Rounds, Parallelization and Strong Encryption Round –Discrete part of the encryption process Parallelization –Use of multiple processes, processors or machines to work on cracking one encryption algorithm Strong encryption –Use of any key longer than 128 bits

30. Symmetric-Key Encryption One key is used to encrypt and decrypt messages

31. Symmetric Algorithms Data encryption standard Triple DES Symmetric algorithms created by RSA Security Corporation International Data Encryption Algorithm Blowfish Twofish Skipjack MARS Rijndael Serpent Advanced Encryption Standard

32. Asymmetric Encryption Asymmetric-key encryption elements –RSA –DSA –Diffie-Hellman

33. Hash Encryption Signing Hash algorithms –MD2, MD4, and MD5 –Secure hash algorithm

34. Applied Encryption Processes E-mail PGP and GPG S-MIME Encrypting drives Web server encryption

35. Summary Create a trust relationship using public-key cryptography List specific forms of symmetric, asymmetric, and hash encryption Deploy PGP in Windows 2000 and Linux

36. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 4: Types of Attacks

37. Objectives Describe specific types of security attacks Recognize specific attack incidents

38. Brute-Force and Dictionary Attacks Brute-force attack –Repeated access attempts Dictionary attack –Customized version of brute-force attack

39. System Bugs and Back Doors Buffer overflow Trojans and root kits

40. Social Engineering and Nondirect Attacks Call and ask for the password Fraudulent e-mail DOS and DDOS attacks Spoofing Trojans Information leakage Hijacking and man-in-the-middle attacks

41. Summary Describe specific types of security attacks Recognize specific attack incidents

42. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 5: General Security Principles

43. Objectives Describe the universal guidelines and principles for effective network security Use universal guidelines to create effective specific solutions

44. Common Security Principles Be paranoid Have a security policy No system stands alone Minimize damage Deploy company- wide enforcement Provide training Integrate security strategies Place equipment according to needs Identify security business issues Consider physical security

45. Summary Describe the universal guidelines and principles for effective network security Use universal guidelines to create effective specific solutions

46. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 6: Protocol Layers and Security

47. Objectives List the protocols that pass through a firewall Identify potential threats at different layers of the TCP/IP stack

48. TCP/IP and Network Security The Internet and TCP/IP were not designed around strong security principles

49. The TCP/IP Suite and the OSI Reference Model Physical layer Network layer Transport layer Application layer Presentation layer Session layer Data link layer

50. TCP/IP Packet Construction TCP Segment Header Body IP Datagram Header Body Ethernet Frames Application Message: e-mail, FTP, Telnet Header Body Trailer

51. Summary List the protocols that pass through a firewall Identify potential threats at different layers of the TCP/IP stack

52. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 7: Securing Resources

53. Objectives Consistently apply security principles Secure TCP/IP services Describe the importance of testing and evaluating systems and services Discuss network security management applications

54. Implementing Security Categorize resources and needs Define a security policy Secure each resource and service Log, test, and evaluate Repeat the process and keep current

55. Resources and Services Protecting services –Protect against profiling –Coordinate methods and techniques –Protect services by changing default settings –Remove unnecessary services

56. Protecting TCP/IP Services The Web Server –CGI scripts –CGI and programming Securing IIS Additional HTTP servers FTP servers –Access control

57. Simple Mail Transfer Protocol The Internet Worm The Melissa virus E-mail and virus scanning Access control measures

58. Testing and Evaluating Testing existing systems

59. Security Testing Software Specific tools –Network scanners –Operating system add-ons –Logging and log analysis tools

60. Security and Repetition Understanding the latest exploits

61. Summary Consistently apply security principles Secure TCP/IP services Describe the importance of testing and evaluating systems and services Discuss network security management applications

62. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 8: Firewalls and Virtual Private Networks

63. Objectives Describe the role a firewall plays in a company’s security policy Define common firewall terms Describe packet-filtering rules Describe circuit-level gateways Configure an application-level gateway Explain PKI Discuss public keys and VPNs

64. The Role of a Firewall Implement a company’s security policy Create a choke point Log Internet activity Limit network host exposure

65. Firewall Terminology Packet filter Proxy server NAT Bastion host Operating system hardening Screening and choke routers DMZ

66. Creating Packet Filter Rules Process –Packet filters work at the network layer of the OSI/RM Rules and fields

67. Packet Filter Advantages and Disadvantages Drawbacks Stateful multi-layer inspection Popular packet-filtering products Using the ipchains and iptables commands in Linux

68. Configuring Proxy Servers Recommending a proxy-oriented firewall Advantages and disadvantages –Authentication –Logging and alarming –Caching –Reverse proxies and proxy arrays –Client configuration –Speed

69. Remote Access and Virtual Private Networks Virtual network perimeter Tunneling protocols IPsec ESP PPTP L2TP

70. Public Key Infrastructure (PKI) Standards –Based on X.509 standard Terminology Certificates

71. Summary Describe the role a firewall plays in a company’s security policy Define common firewall terms Describe packet-filtering rules Describe circuit-level gateways Configure an application-level gateway Explain PKI Discuss public keys and VPNs

72. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 9: Levels of Firewall Protection

73. Objectives Plan a firewall system that incorporates several levels of protection Describe the four types of firewall systems design and their degrees of security Implement a packet-filtering firewall

74. Firewall Strategies and Goals Resource placement Physical access points Site administration Monitoring tools Hardware

75. Building a Firewall Design principles –Keep design simple –Make contingency plans

76. Types of Bastion Hosts Single-homed bastion host Dual-homed bastion host Single-purpose bastion hosts –Internal bastion hosts

77. Hardware Issues Operating system Services Daemons

78. Common Firewall Designs Screening routers Screened host firewall (single-homed bastion) Screened host firewall (dual-homed bastion) Screened subnet firewall (demilitarized zone)

79. Summary Plan a firewall system that incorporates several levels of protection Describe the four types of firewall systems design and their degrees of security Implement a packet-filtering firewall

80. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 10: Detecting and Distracting Hackers

81. Objectives Customize your network to manage hacker activity Implement proactive detection Distract hackers and contain their activity Set traps Deploy Tripwire for Linux

82. Proactive Detection Automated security scans Login scripts Automated audit analysis Checksum analysis

83. Distracting the Hacker Dummy accounts Dummy files Dummy password files Tripwires and automated checksums Jails

84. Punishing the Hacker Methods Tools

85. Summary Customize your network to manage hacker activity Implement proactive detection Distract hackers and contain their activity Set traps Deploy Tripwire for Linux

86. Copyright © 2002 ProsoftTraining. All rights reserved. Lesson 11: Incident Response

87. Objectives Respond appropriately to a security breach Identify some of the security organizations that can help you in case your system is attacked Subscribe to respected security alerting organizations

88. Decide Ahead of Time Itemize a detailed list of procedures Include the list in a written policy Be sure all employees have a copy

89. Incident Response Do not panic Document everything Assess the situation Stop or contain the activity Execute the response plan Analyze and learn

90. Summary Respond appropriately to a security breach Identify some of the security organizations that can help you in case your system is attacked Subscribe to respected security alerting organizations

91. Network Security and Firewalls What Is Security? Elements of Security Applied Encryption Types of Attacks General Security Principles Protocol Layers and Security

92. Network Security and Firewalls Securing Resources Firewalls and Virtual Private Networks Levels of Firewall Protection Detecting and Distracting Hackers Incident Response