ICANN Acronyms and Terms
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Internet Protocol version 4(IPv4)
The first version of the Internet Protocol (IP) to gain popular use. The Defense Advanced Research Projects Agency developed IPv4 in the early 1980s. With an address length of 32 bits, IPv4 has a capacity of just over four billion unique IP addresses. After years of rapid Internet expansion, its pool of available addresses has been fully allocated to Internet services providers and users.
IPv4 addresses are written as a sequence of four decimal values between 0 and 255, separated by dots. A typical IPv4 address looks like this: 192.0.2.67.