Network Security Fundamentals

Diffie-Hellman

• Diffie-Hellman is a key exchange protocol.
• It allows two parties to securely establish a shared secret key over an insecure channel.

Authentication Protocols

• Authentication protocols verify the identity of users or systems.
• Examples include username/password, multi-factor authentication.

Block Cipher Chaining Modes

• Block cipher chaining modes combine multiple blocks of plaintext to enhance security.
• Modes like CBC (Cipher Block Chaining) and CTR (Counter) are used in encryption.

DNS

• DNS (Domain Name System) has three levels of servers (root, authoritative, recursive).
• DNS queries can be iterative or recursive.
• DNS uses caching to improve performance.
• DNS message format includes headers, questions, answers, and authority records.
• Cache poisoning is a security vulnerability where malicious data is injected into the DNS cache, and can be mitigated via DNSSEC.

WiFi

• WiFi Basic Service Set (BSS) is the fundamental building block of a wireless LAN.
• Access point scanning methods exist to detect available WiFi networks.
• WiFi message formats vary depending on the standard.
• WEP, WPA, and WPA2 are security protocols for WiFi, with various levels of encryption and authentication.

Email

• SMTP (Simple Mail Transfer Protocol) is used for email transmission.
• Email services can provide confidentiality, message integrity, and sender authentication.
• PGP (Pretty Good Privacy) is a popular email encryption and decryption standard.
• Spam protocols filter out unwanted emails.

Anonymity

• SOCKS and Tor are anonymity systems.
• Tor uses various cryptographic algorithms to protect user anonymity.
• Tor protects against attacks by routing traffic through several nodes.

IPsec

• IPsec (Internet Protocol Security) uses security associations for establishing secure communication channels.
• IPsec protocols AH (Authentication Header) and ESP (Encapsulating Security Payload) offer authentication and encryption.
• IKEv2 (Internet Key Exchange version 2) establishes security associations and protects against attacks.

Web

• XSS (Cross-Site Scripting) vulnerabilities can exist on either the client-side or server-side.
• SQL injection exploits vulnerabilities in web applications that interact with databases.
• Slowloris is a denial-of-service attack targeting web servers.
• Heap spray is a memory management technique used in denial-of-service or other attacks.

Transport Layer

• Shrew DoS is a Denial-of-Service attack targeting the transport layer.
• TCP SYN floods are denial-of-service attacks exploiting the TCP three-way handshake.
• IP address spoofing is a technique used to hide the source IP address of a malicious connection.
• SSL/TLS (Secure Sockets Layer/Transport Layer Security) ensures secure connections.
• SSL/TLS session/connection, record protocol, and handshake protocol are vital components ensuring secure communication.
• Heartbeat protocol is used to detect connectivity issues within SSL connections; but a vulnerable implementation can cause server-side problems.

This quiz covers essential concepts in network security, including key exchange protocols like Diffie-Hellman, authentication mechanisms, block cipher chaining modes, and the intricacies of the Domain Name System (DNS). Test your knowledge on these foundational topics and enhance your understanding of secure communications.