Firewall
A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It acts as a barrier between a trusted internal network and untrusted external networks, such as the internet, to prevent unauthorized access and cyber threats. Basic firewalls typically operate at the network layer (Layer 3) and transport layer (Layer 4) of the OSI model, filtering traffic based on IP addresses, ports, and protocols.
Developers should learn about basic firewalls to secure applications and infrastructure by implementing access controls and protecting against common attacks like DDoS or unauthorized intrusions. This is essential for roles involving DevOps, cloud computing, or any system exposed to the internet, such as web servers or APIs, to ensure compliance and data safety. Understanding firewalls helps in configuring network policies and troubleshooting connectivity issues in development and production environments.