But firstly, what happened to IPv5? In 1979, Internet Stream Protocol (ST) was considered IP version five by industry researchers, but ST was abandoned before ever becoming a standard or widely known as IPv5.
It is common to see examples that attempt to show that the IPv6 address space is absurdly large. IPv6 supports 2128 (about 3.4×1038) addresses, or approximately 5×1028 addresses for each of the roughly 7 billion people alive today.
IPv6 addresses are normally written as eight groups of four hexadecimal digits. For example,
IPv6 is implemented on all major operating systems in use in commercial, business, and home consumer environments. But IPv4 still carries the vast majority of Internet traffic. In September 2013, the percentage of users reaching Google services over IPv6 only surpassed 2% for the first time.
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