IPv4 was the first version of the protocol to be widely adopted. However, at just 32-bits, the 4.3 billion available addresses don’t even give one address to each living person.
IPv6 was developed to allow the internet to continue to grow at pace. At 128-bits, IPv6 provides an almost limitless supply of IP addresses.
IPv6 has other advantages including: easier to configure; supports more efficient usage of broadband; it is compatible with 3G wireless broadband.
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