Lesson 6: Network Security
Week of Mon, Oct 26 · lesson closes Sun, Nov 1
By the end of this lesson you can:
- →Explain multi-factor authentication factors and access control principles. CCR-5 MSDE-CTE-IT-6.1 MSDE-CTE-IT-7.1 FC0-U71 3.6
- →Describe how symmetric encryption, asymmetric encryption, and hashing protect data. CCR-5 MSDE-CTE-IT-6.1 MSDE-CTE-IT-7.1 FC0-U71 3.6
- →Identify the purpose of firewalls, IDS/IPS, and SIEM tools in a layered security model. CCR-5 MSDE-CTE-IT-6.1 MSDE-CTE-IT-7.1 FC0-U71 3.6
- →Identify common cybersecurity threats including phishing, malware, and social engineering. CCR-5 MSDE-CTE-IT-6.1 MSDE-CTE-IT-7.1 FC0-U71 3.6
Take Meerk's quiz for Lesson 6
This lesson's items
Exact due times are in Canvas.
Watch — Professor Messer
Professor Messer's Free Security+ SY0-701 Training Course
Free, independent educational resource. Not affiliated with or endorsed by CompTIA. Watch, then read the notes below.
Know these cold
Common Threats
- Phishing uses fake emails to steal credentials or deliver malware; spear phishing targets specific individuals.
- DoS (Denial of Service) floods a target with traffic; DDoS uses many compromised systems (botnet) simultaneously.
- Man-in-the-Middle (MitM) intercepts communication between two parties; often on unencrypted Wi-Fi.
- SQL injection inserts malicious SQL code into a web form input to manipulate a backend database.
Authentication and Access
- Authentication factors: something you know (password), have (token/smart card), are (biometric). MFA uses two or more.
- Passwords should be ≥12 characters, mix upper/lower/numbers/symbols, and be unique per account.
- Password managers securely store and generate unique passwords; preferred over reusing passwords.
- Account lockout policies prevent brute-force attacks by locking accounts after N failed login attempts.
Encryption Basics
- Symmetric encryption uses one key (AES-256 is standard); fast but key distribution is a challenge.
- Asymmetric encryption uses a key pair (RSA, ECC); public key encrypts, private key decrypts; solves key distribution.
- HTTPS uses TLS (Transport Layer Security) to encrypt web traffic between browser and server.
- Hashing (SHA-256) produces a fixed-length fingerprint of data; one-way — cannot be reversed.
Firewalls and Monitoring
- Firewalls filter traffic by IP, port, and protocol; stateful firewalls track connection state.
- An IDS (Intrusion Detection System) detects and alerts; an IPS (Intrusion Prevention System) also blocks.
- Antivirus uses signatures (known malware) and heuristics (behavioral detection) to find malware.
- Log monitoring and SIEM (Security Information and Event Management) aggregate events for threat detection.
Quick check — before the quiz
1. Which attack floods a target with traffic from many compromised computers?
2. MFA requires authentication using:
Meerk's quiz — open the Lesson 6 gate
10 questions, no time limit. 85% on your first attempt in a 24-hour window opens the gate. Retakes inside the window are practice — they help you learn, they don't count. Work alone; the point is to know it, not to have seen it.
Stuck?
Raise your hand. Mr. James gets a message right away and can help you remotely. Nothing else is stored — just your last name, grade, and where you're stuck.
Dinner Table Question
Ask at home: Have you ever created the same password for multiple accounts? Why is that dangerous?
En español: ¿Alguna vez usaste la misma contraseña en varias cuentas? ¿Por qué es peligroso?