When using iptables, the '''Filter''' table is important; it contains these '''three chains''':
:*'''INPUT:''' Packets are checked against the INPUT chain to see if it is '''allowed into''' the PC:*'''OUTPUT:''' Packets are checked against the OUTPUT chain to see if it is <u>allowed to go outside</u> of the PC:*'''FORWARD:'''PC is acting as a router it does not actually send or receive data, it <u>FORWARDS</u> data from one machine to another
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