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P-2000W_V2 User’s Guide
The following table summarizes how these NAT types handle outgoing and incoming packets. Read the following sections for more details and examples.
Table 12 | NAT Types |
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| FULL CONE | RESTRICTED | PORT | SYMMETRIC |
| RESTRICTED | |||
| CONE | |||
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| CONE |
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Incoming | Any external host | Only external hosts | Only external hosts | A host on the external |
Packets | can send packets to | with an IP address | with an IP address | network can only send |
| the mapped | to which the internal | and port to which | packets to the specific |
| external IP address | host has already | the internal host | mapped external IP |
| and port. | sent a packet can | has already sent a | address and port that the |
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| send packets to the | packet can send | NAT router used in |
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| mapped external IP | packets to the | sending a packet to the |
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| address and port. | mapped external IP | external host’s IP address |
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| address and port. | and port. |
Outgoing | The NAT router maps the internal IP address and port of all | The NAT router maps the | ||
Packets | outgoing packets to a single IP address and port on the | internal IP address and | ||
| external network. |
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| port of each outgoing |
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| packet to a different |
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| external IP address and |
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| port for each different |
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| destination IP address |
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| and port. |
The examples in these NAT type sections describe NAT translation between internal (private) and external (public) IP addresses.
12.11.2.1 Full Cone NAT
In full cone NAT, the NAT router maps all outgoing packets from an internal IP address and port to a single IP address and port on the external network. The NAT router also maps packets coming to that external IP address and port to the internal IP address and port.
In the following example, the NAT router maps the source address of all packets sent from the Prestige’s internal IP address 1 and port A to IP address 2 and port B on the external network. The NAT router also performs NAT on all incoming packets sent to IP address 2 and port B and sends them to IP address 1, port A.
| Chapter 12 User Web Configurator Screens | 85 |
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