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[>_] ROOM · Networking
Firewall Fundamentals and Stateful Inspection
Master firewall architectures, packet filtering, stateful inspection, and zone-based security to defend enterprise network perimeters.
Room tasks
1What Is a Firewall and Why Does It Matter
2Stateful vs Stateless Filtering
3Configuring Access Control Lists (ACLs)
4Next-Gen Firewall Features
5Guided Lab: Building ACLs to Segment Network Traffic
Frequently Asked Questions
What is a stateful firewall?
A stateful firewall tracks the state of connections and allows return traffic for sessions it has seen. This is smarter and safer than inspecting each packet in isolation.
What is the difference between stateless and stateful filtering?
Stateless filtering judges each packet by header rules only, while stateful inspection remembers connections. Stateful filtering blocks unsolicited inbound packets that merely look valid.
How do zone-based firewalls work?
Interfaces are grouped into zones, and policy defines what traffic may pass between them. This free intermediate Codelivly room shows how to design such rules.