LEARNING PATH

Networking Fundamentals

From the OSI model and TCP/IP up through everyday protocols like HTTP, DNS, and SSH — build the network foundation every security learner needs.

16 lessons
  1. The OSI Reference Model — Seven Layers and How They Map to TCP/IP The ISO Basic Reference Model (Open Systems Interconnection Reference Model) is the 1984 i...
  2. TCP/IP Explained — The 4-Layer Model and TCP vs UDP TCP/IP names both 'the protocol suite that runs the Internet' and 'the four-layer referenc...
  3. IP Addresses Explained — IPv4 / IPv6 / Subnets / Routing IP (Internet Protocol) handles addressing and packet forwarding at the heart of the TCP/IP...
  4. What Is NAT? — Translating Private IPs to a Public IP, and Port Forwarding NAT (Network Address Translation) rewrites IP addresses as packets cross a border router....
  5. Ethernet Explained — Frame Format, MAC Addresses, and Switching Ethernet is the L2 protocol that has survived nearly 50 years as the only practical choice...
  6. What Is ARP? — Resolving a MAC Address from an IP Address ARP (Address Resolution Protocol) is the foundational IPv4 protocol that asks, on a local...
  7. What Is a VLAN? — Splitting One Switch Logically at Layer 2 A VLAN (Virtual LAN) logically divides one physical switch / one physical network into sev...
  8. ICMP Explained — How ping and traceroute Work and What the Message Types Mean ICMP is the control protocol that signals errors and path conditions on IP networks. This...
  9. What Is DHCP? — The DORA Flow That Hands Out IP Addresses Automatically DHCP (Dynamic Host Configuration Protocol) automatically assigns an IP address, subnet mas...
  10. DNS Explained — How Name Resolution Works and the Record Types DNS is the distributed database that converts memorable domain names into the IP addresses...
  11. HTTP/HTTPS HTTP/HTTPS is the protocol the World Wide Web uses to move content. This article covers th...
  12. SSL/TLS Explained — How HTTPS Encrypts the Web and How Certificates Work SSL/TLS is the protocol that gives Internet traffic confidentiality, authentication, and t...
  13. SSH — How It Works, Public-Key Authentication, and Essential Commands SSH is the protocol for operating another computer safely over the network. It replaced cl...
  14. VPN Explained — IPsec, OpenVPN, and WireGuard Compared A VPN (Virtual Private Network) is the umbrella term for virtually stretching an 'encrypte...
  15. IPsec Explained — Tunnel/Transport Modes and the IKE Key Exchange IPsec is a family of protocols that encrypts and authenticates IP packets themselves at L3...
  16. Wi-Fi (IEEE 802.11) Explained — Standards, Bands, and WPA Wi-Fi shares Ethernet's frame format but rides on radio waves — a shared medium, half-dupl...