NAT Port Allocation
In an integrated scenario, a NAT device initiates NAT port allocation after receiving the first packet sent by a specific private IP address.
Dynamic Port Allocation
Dynamic port pre-allocation (Port Dynamic) enables a NAT device to pre-allocate a public IP address and a port range with 64 ports to a private IP address. If the number of used ports exceeds the initial port range size, the NAT device assigns another port range with 64 ports to the user. The allocation process repeats without a limit on the maximum number of extended port ranges.
Dynamic port allocation supports interface multiplexing. When receiving packets destined for different public IP addresses, a NAT device can map the private IP addresses and port numbers to the same public IP address and port number, which saves public IP addresses.