The exhaustion of the IPv4 pool was already foreseen in the 1990s.
With the rapid growth of the Internet after commercialization in the 1990s, it became evident that far more addresses than the IPv4 address space has available were necessary to connect new devices in the future. By 1998, the Internet Engineering Task Force (IETF) had formalized the successor protocol. IPv6 uses a 128-bit address, theoretically allowing 2128 or approximately 3.4×1038 addresses.
Next to the large number of addresses IPv6 provides multiple features over IPv4. NAT is no longer required, IPv6 performs MTU path detection and allows for easier routing on internal networks.