CCNA Cisco Netacad: Network Security Fundamentals

Introduction

• Focus on:
  • Configuring switches and routers for security
  • Security threats and vulnerabilities
  • Network attacks and mitigation
  • Device security

Security Threats and Vulnerabilities

Types of Threats

• Information Theft: Unauthorized access to confidential information (e.g., social insurance numbers).
• Data Loss and Manipulation: Destroying or altering data records (e.g., changing grades or reformatting hard drives).
• Identity Theft: Stealing personal data to assume someone else's identity. Affects individuals and corporations.
• Disruption of Services: Preventing legitimate access to services (e.g., DDoS attacks).

Types of Vulnerabilities

• Technological Vulnerabilities:
  • TCP/IP protocol weaknesses
  • OS security issues
  • Network equipment weaknesses
• Configuration Vulnerabilities:
  • Unsecured accounts
  • Default settings and passwords
  • Misconfigured services
• Security Policy Vulnerabilities:
  • Lack of policies
  • Authentication issues
  • No disaster recovery plan

Network Attacks

Types of Malware

• Viruses: Attach to executables; need user action to spread.
• Worms: Standalone; exploit vulnerabilities to spread without user help.
• Trojan Horses: Appear legit; create backdoors for unauthorized access.

Types of Network Attacks

• Reconnaissance Attacks: Mapping systems and vulnerabilities.
• Access Attacks: Unauthorized data/system access.
• Denial of Service (DoS) Attacks: Disrupting communication by overwhelming systems.

Access Attack Techniques

• Password Attacks: Brute force, trojans, packet sniffers
• Trust Exploitation: Misuse of privileged access.
• Port Redirection: Using a compromised system to attack others.
• Man-in-the-Middle (MitM): Intercepting and altering communications.

Network Attack Mitigation

Defense in Depth

• VPN: Secure tunnels for remote access.
• Firewalls: Prevent unauthorized access.
• Intrusion Prevention System (IPS): Monitors and responds to detected threats.
• AAA (Authentication, Authorization, Accounting): Control access and track usage.

Security Strategies

• Regular updates and patches for OS and software.
• Strong and regularly changed passwords.
• Encrypting communications (e.g., SSH).

Device Security

Cisco Auto Secure

• Default security settings are inadequate; use Auto Secure to enhance security.

Practical Security Measures

• Change default usernames and passwords.
• Restrict resource access
• Disable unnecessary services.
• Regular backups stored securely off-site.

Conclusion

• Review key points including types of threats, vulnerabilities, network attacks, and mitigation strategies.
• Importance of strong security policies and proactive device management.