Network Security: Basic Principles

Network security is about protecting the integrity, confidentiality, and availability of data as it travels across or is stored in computer networks. It ensures that only authorized users can access resources, while keeping attackers out.

Core Principles (CIA Triad)

• Confidentiality – Preventing unauthorized access to sensitive data.
• Integrity – Ensuring data is not altered or tampered with.
• Availability – Making sure resources are accessible to authorized users when needed.

Basic Network Security Measures

• Firewalls – Control and filter incoming/outgoing network traffic.
• Intrusion Detection & Prevention Systems (IDS/IPS) – Monitor networks for suspicious activity.
• Encryption – Secures data during transmission (e.g., HTTPS, VPN).
• Access Controls – Ensuring only authorized devices and users can connect.
• Regular Updates & Patching – Closing security holes in network devices and software.

Common Threats

• Unauthorized Access – Hackers gaining entry to the network.
• Man-in-the-Middle (MITM) Attacks – Intercepting and altering communications.
• Denial of Service (DoS/DDoS) – Overloading a network to make it unavailable.
• Malware Propagation – Spreading viruses or worms across the network.

Best Practices

• Use strong Wi-Fi encryption (WPA3 or WPA2).
• Change default router and device passwords.
• Segment networks (e.g., guest Wi-Fi separate from main).
• Monitor network activity regularly.
• Educate users on safe connection practices.

Key Takeaway

Network security is built on layered protection—a mix of technology, monitoring, and safe user practices. A secure network keeps data safe, prevents intrusions, and ensures smooth operations.