Cybersecurity
Firewall
Definition
A firewall is a network security device that monitors incoming and outgoing network traffic and decides whether to allow or block specific traffic based on a defined set of security rules.
Why It Matters
Firewalls are a first line of defense in network security. They establish a barrier between a trusted internal network and an untrusted external network, such as the Internet.
Contextual Example
A company configures its firewall to block all incoming traffic except for requests to its public web server on port 443. This prevents attackers from directly accessing internal servers and databases.
Common Misunderstandings
- Firewalls can be hardware devices, software programs, or both.
- While essential, a firewall is not a complete security solution and must be part of a layered security strategy.