Security & Networking Foundations
Security first principles and the network stack for defenders — CIA triad, threat modeling, TCP/IP, the Linux CLI, cryptography, and identity & access.
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Course Content
Foundations
Core concepts and groundwork
CIA Triad, Threat Actors and Attack Surfaces
Reading
Risk, Threat, Vulnerability and Likelihood vs Impact
Reading
Security Frameworks — NIST CSF, ISO 27001, CIS Controls
Reading
Defense in Depth and Zero-Trust Principles
Reading
Common Attack Lifecycle — MITRE ATT&CK Overview
Reading
Practice — Build a Threat Model for a Sample Web App
Exercise
Core Skills
Essential techniques and patterns
OSI and TCP/IP Models for Security Engineers
Reading
IP Addressing, Subnetting and NAT
Reading
DNS — Resolution, Records and Abuse (Spoofing, Tunnelling)
Reading
HTTP/HTTPS Lifecycle and TLS Handshake Walkthrough
Reading
Firewalls, Proxies, Load Balancers and WAFs
Reading
Practice — Capture and Analyse Traffic with Wireshark
Exercise
Applied Practice
Hands-on, real-world scenarios
Linux File Permissions, Ownership and Sudo Model
Reading
Processes, Services and Systemd Hardening Basics
Reading
Users, Groups and SSH Key-Based Authentication
Reading
Bash Scripting for Security Automation
Reading
Log Files and Syslog — Where Evidence Lives
Reading
Practice — Harden a Fresh Ubuntu Server Checklist
Exercise
Advanced Topics
Deeper, more complex material
Symmetric vs Asymmetric Encryption — AES, RSA, ECC
Reading
Hashing, Salting and Password Storage (bcrypt, Argon2)
Reading
Digital Signatures and Certificate Chains
Reading
PKI — CAs, CSRs and Certificate Lifecycle
Reading
TLS 1.3 Improvements and Common Misconfigurations
Reading
Practice — Generate Keys, Certs and Sign Data with OpenSSL
Exercise
Production & Scale
Building for the real world
Authentication Factors — Passwords, MFA, Biometrics
Reading
Authorization Models — RBAC, ABAC and Least Privilege
Reading
Session Management and Cookie Security Attributes
Reading
SSO Concepts — SAML, OAuth 2.0 and OIDC at a Glance
Reading
Password Policies, Credential Stuffing and Breach Data
Reading
Practice — Configure MFA and Session Hardening on a Demo App
Exercise
Mastery & Capstone
Projects and final review
Project Brief — Segmented Network for a Small SaaS Company
Reading
Design Subnets, Firewall Rules and DMZ
Exercise
Implement TLS, Hardened SSH and MFA on Lab Hosts
Exercise
Document Threat Model and Risk Register
Exercise
Capstone — Submit Secure Network Design Portfolio
Project
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Topic Overview
What you'll learn
- Core concepts and fundamentals of Security & Networking Foundations
- Industry best practices and design patterns
- Hands-on exercises with real-world scenarios
- Performance optimization and advanced techniques
- Building production-ready applications