Network Security & Defense — Illustrated Study Guide

A vendor-neutral, defender-first study guide for the Network Security & Defense certification. Five modules build real defensive judgement: network models and segmentation, firewalls and access control, secure remote access and encryption, secure DNS and wireless, and monitoring with defense-in-depth architecture. Rich with Mermaid diagrams (segmented/DMZ topology, firewall rule evaluation, IPSec tunnel, TLS handshake, IDS/IPS placement), comparison tables (firewall types, VPN protocols, WPA generations), worked examples, and self-checks. Every topic is taught from the blue-team perspective: how to defend, detect, and respond.

Key facts

• Course price: $91 (one-time payment)
• Field: Cybersecurity & Information Security
• Prepares for: Network Security & Defense
• 5 modules · 15 lessons · about 3 hours of lessons
• Self-paced, online, illustrated lessons

Course outline

1. Network Models and Segmentation — Reading the OSI/TCP-IP stack through a security lens, then dividing the network into defended zones with VLANs and a DMZ.
   • The OSI and TCP/IP Models for Defenders
   • Network Segmentation and VLANs
   • The DMZ and Secure Zoning
2. Firewalls and Access Control — Stateful and next-generation firewalls, designing and ordering rules, and detecting intrusions with IDS/IPS.
   • Stateful Firewalls and NGFWs
   • Designing Firewall Rules
   • Intrusion Detection and Prevention (IDS/IPS)
3. Secure Remote Access and Encryption — VPNs with IPSec and SSL/TLS for remote access, and the TLS/PKI/certificate trust that underpins secure communication.
   • VPNs: IPSec and SSL/TLS
   • TLS and the Handshake
   • PKI, Certificates, and Trust
4. Secure DNS and Wireless — Hardening DNS with DNSSEC and encrypted DNS, securing Wi-Fi with WPA2/WPA3 and 802.1X, and enforcing posture with NAC and zero trust.
   • Securing DNS and DNSSEC
   • Wi-Fi Security: WPA2, WPA3, and 802.1X
   • NAC and Zero-Trust Networking
5. Monitoring and Defense in Depth — Defending against classic network attacks, monitoring with logs and NetFlow, and tying it together in a layered, hardened architecture.
   • Defending Against Common Network Attacks
   • Logging, Monitoring, and NetFlow
   • Defense in Depth and Secure Architecture