Chapter 13 Network Security Auditing Antivirus Firewalls Authentication Authorization Encryption

Security Policy Steps Assets Threats Vulnerabilities Risk Protective measure –Virus protection –Firewall –Authentication –Encryption

Auditing Personal: internal or external Methods –Manual auditing: policy auditing or off-line audit (policy development & implementation) –automated auditing: event detection or real-time audits (software & exception reports) –Security probes: weak spots & improvement Intrusion detection systems or Security Analyzer Tool for Analyzing Networks (SATAN) Courtney

Antivirus Technology Virus scanning: signature scanners Emulation technology: activity monitors (virtual PC) CRC checkers: hashing checkers

Firewall Architectures Packet filtering Application gateway

Packet Filtering Port-level filter, network-level filter, or packet filter Filter tables: source and destination addresses Weakness: IP spoofing

Application Gateways Application-level filters, assured pipe-lines, application gateways, or proxies Sources, services or application Weakness –Inability to detect malicious code

Firewall Functions Encryption Virus scanning Violation notification Authentication System monitoring Auditing and logging Attack protection

Authentication categories –What you know –What you have –What you are Types –Token authentication –Biometric authentication

Encryption methods Private key encryption –Same algorithm –Data encryption standard (DES): 64-bit key Public key encryption –Rivest-Shamir-Adelman: RSA –Public/private key encryption Digital signature encryption –Private key, hashing program, original document

Assignment Review chapters 8, 9, & 13