4. You may add more firewall rules for specific security purposes. Click on the Add radio button at the screen shown above, followed by the Edit button and the screen on the left will appear.
Rule Name : Enter a unique name to identify this firewall rule.
Disposition : This parameter determines whether the packets obeying
Policythe rule should be accepted or denied by the firewall. Choose between Accept and Deny.
Protocols : Users are allowed to select the type of data packet from: TCP, UDP, ICMP, IGMP or ALL.
Note: If users select either ICMP or IGMP, they are required to make further selection in the ICMP Types or IGMP Types respectively.
ICMP Types | : This IP protocol is used to report errors in IP packet | |||||
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| routing. ICMP serves as a form of flow control, although | ||||
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| ICMP messages are neither guaranteed to be received | ||||
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| or transmitted. |
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| ICMP | Description |
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| Packet Type |
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| Echo | Determines | whether | an IP |
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| request | node (a host or a router) is |
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| available on the network. |
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| Echo reply | Replies to an ICMP echo |
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| request. |
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| Destination | Informs the host that a |
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| unreachabl | datagram | cannot | be |
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| e | delivered. |
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| Source | Informs the host to lower the |
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| quench | rate at which it | sends |
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