While static NAT provides a permanent mapping between an inside local address and an inside global address, dynamic NAT allows the automatic mapping of inside local addresses to inside global addresses. These inside global addresses are typically public IPv4 addresses. Dynamic NAT uses a group, or pool of public IPv4 addresses for translation.
Dynamic NAT, like static NAT, requires the configuration of the inside and outside interfaces participating in NAT. However, where static NAT creates a permanent mapping to a single address, dynamic NAT uses a pool of addresses.