From the course: Firewall Administration Essential Training

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Create firewall rules

Create firewall rules

From the course: Firewall Administration Essential Training

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Create firewall rules

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- [Instructor] Firewall rules control what traffic is allowed to enter an interface on the firewall. We say enter whether we mean from the WAN side or the LAN side. A funny way to think about this is that and you can imagine bureaucrats processing data packets through the various places they want to go as if customs agents in the world's most confusing airport customs area with multiple customs desks and multiple doors numbering in the tens of thousands for travelers numbering in the billions or more. Once traffic is passed through on an interface the firewall places an entry into its state table. Then the state table entry allows through subsequent packets that are part of that same connection. It's kind of like a family traveling through customs except only one parent needs to show their passport and the rest of the group goes through by virtue of being let through on the initial inspection. Firewall rules are processed from the top down stopping at the first match. If no…

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