Dynamic conversion means that when converting the private IP address of the internal network to a public IP address, the IP address pair is not determined, but random. All private IP addresses authorized to access the Internet can be randomly converted to any specified legal IP. address. That is, dynamic translation is possible as long as you specify which internal addresses can be translated, and which legal addresses are used as external addresses. Dynamic translation can use multiple sets of legal external addresses.
The following will be an experiment on this topology.
The target
PC1 PC2 is converted to the address of the 12.0.0.0 network segment when accessing PC3 
1: Set the IP and gateway of PC1 PC2 PC3 
2: Turn off the router function of the switch SW to
make the interface f1/0 duplex match
3: Configure router R1
configure interface f0/1 duplex matching set IP and enable
configure interface f0/0 set IP and enable
define access control list to allow IP of 192.168.10.0 network segment by
defining legal IP address pool 12.0.0.10 -12.0. 0.20
Convert the local address in ACL1 to the global address in the zkc address pool
Enable NAT on the port and
exit to privileged mode Enable NAT detection debug ip nat
4: Use PC1 PC2 ping PC3
R1 to set up detection NAT to see the details of address translation
