vohongnhuy1996 blog

Security tools and techniques series – Part 1: Firewall

What is firewall?

Firewalls are devices or programs that monitors incoming and outgoing network traffic and permits or blocks data packets based on a set of security rules.

Types of firewalls

  • Hardware Firewalls: Dedicated devices like Cisco ASA, Fortinet.
  • Software Firewalls: Runs on servers, e.g., Windows Defender Firewall, iptables.
  • Next-Generation Firewall (NGFW): Integrates deep packet inspection (DPI) and threat detection.

How it works

  • Packet Filtering: Filters packets based on IP, port, and protocol.
  • Stateful Inspection: Tracks connection states.
  • Proxy-based Firewall: Acts as an intermediary between client and server.
  • Deep Packet Inspection (DPI): Analyzes data content.

If you found this helpful, you can buy me a coffee and keep me going. Thank you!
https://buymeacoffee.com/vohongnhuy1996

Võ Hồng Như Ý – 05/02/2025

Leave a comment