About this interactive
The firewall in this activity is set up the way the lesson describes:
- Traffic from **inside** the network may go **out** to the internet.
- **Return traffic** may come back in, after the firewall checks it is the traffic an inside device requested.
- Anything else from **outside** trying to get in is **blocked**, so nobody on the internet can just access the network.
A router locked down with access control lists can do some of this; a dedicated firewall adds deeper packet inspection.
What you'll learn
- Predict whether a firewall set up as the lesson describes allows or blocks traffic: inside traffic may go out, its replies may come back in, and unrequested traffic from outside is blocked
- Recognise that the firewall inspects returning traffic to make sure it is traffic an inside device requested
Aligned to
CompTIA Network+
4.1
Explain the importance of basic network security concepts
Cisco CCST Networking
6.1
Describe how firewalls operate to filter traffic
Key terms
- Firewall
- A network security device that monitors and controls incoming and outgoing traffic based on predefined security rules.
- Stateful Firewall
- A firewall that tracks the state of active network connections and makes filtering decisions based on context.
- Packet Filtering
- A firewall technique that inspects packets and allows or blocks them based on source, destination, and protocol.
- Access Control List
ACL
- A set of rules that defines which users or systems are granted or denied access to a resource.
Topics
Firewall
Stateful Inspection
Network Security
Interactive
Streak Sort
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