System and Network Security:
A Comprehensive Introduction

Building a Secure Organisation

Real threats that impact cybersecurity

• Hackers inside and out
• Eavesdropping
• Spoofing
• Sniffing
• Trojan horses
• Viruses
• Wiretaps

A cybersecurity policy: the foundation of your protection

• Defining your information assurance objectives
• Assessing your exposure

A Cryptography Primer

Securing data with symmetric encryption

• Choosing your algorithm: DES, AES, RC4 and others
• Assessing key length and key distribution

Solving key distribution issues with asymmetric encryption

• Generating keys
• Encrypting with RSA
• PGP and GnuPG
• Evaluating Web of Trust and PKI

Ensuring integrity with hashes

• Hashing with MD5 and SHA
• Protecting data in transit
• Building the digital signature

Verifying User and Host Identity

Assessing traditional static password schemes

• Creating a good quality password policy to prevent password guessing and cracking
• Protecting against social engineering attacks
• Encrypting passwords to mitigate the impact of password sniffing

Evaluating strong authentication methods

• Challenge-response to prevent man-in-the-middle attacks
• Preventing password replay using one-time and tokenised passwords
• Employing biometrics as part of two-factor authentication

Authenticating hosts

• Shortcomings of IP addresses
• Address-spoofing issues and countermeasures
• Solutions for wireless networks

Preventing System Intrusions

Discovering system vulnerabilities

• Searching for operating system holes
• Discovering file permission issues
• Limiting access via physical security

Encrypting files for confidentiality

• Encryption with application-specific tools
• Recovering encrypted data

Hardening the operating system

• Locking down user accounts
• Securing administrator's permissions
• Protecting against viruses

Guarding against Network Intrusions

Scanning for vulnerabilities

• Restricting access to critical services
• Preventing buffer overflows

Reducing denial-of-service (DoS) attacks

• Securing DNS
• Limiting the impact of common attacks

Deploying firewalls to control network traffic

• Contrasting firewall architectures
• Preventing intrusions with filters
• Implementing cybersecurity policy

Building network firewalls

• Evaluating firewall features
• Selecting an architecture and a personal firewall

Ensuring Network Confidentiality

Threats from the LAN

• Sniffing the network
• Mitigating threats from connected hosts
• Partitioning the network to prevent data leakage
• Identifying wireless LAN vulnerabilities

Confidentiality on external connections

• Ensuring confidentiality with encryption
• Securing data-link layer with PPTP and L2TP
• Middleware information assurance with SSL and TLS
• Deploying SSH (the Secure Shell)

Protecting data with IPsec

• Authenticating remote locations
• Tunnelling traffic between sites
• Exchanging keys

Managing Your Organisation's Security

• Developing a security plan
• Responding to incidents
• Enumerating the six critical steps