Source NAT changes the destination address of IP packets as they pass through the router.

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Multiple Choice

Source NAT changes the destination address of IP packets as they pass through the router.

Source NAT rewrites the source IP address of outgoing packets, not the destination. When a host from the internal network sends a packet outward, the NAT device replaces the internal source IP with its own external IP (and often the port as well, in PAT) so replies come back to the NAT. The destination address remains the original target address on the outside network, which is why the packet can reach the intended destination. If the destination address were changed, that would be DNAT, not Source NAT.

Source NAT rewrites the source IP address of outgoing packets, not the destination. When a host from the internal network sends a packet outward, the NAT device replaces the internal source IP with its own external IP (and often the port as well, in PAT) so replies come back to the NAT. The destination address remains the original target address on the outside network, which is why the packet can reach the intended destination. If the destination address were changed, that would be DNAT, not Source NAT.

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