An IP address serves two principal functions: it identifies the host, or more specifically its network interface, and it provides the location of the host in the network, and thus the capability of establishing a path to that

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Two versions of the Internet Protocol are in common use on the Internet today. The original version of the Internet Protocol that was first deployed in 1983 in the ARPANET,

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IP networks may be divided into subnetworks in both IPv4 and IPv6. For this purpose, an IP address is recognized as consisting of two parts: the network prefix in the high-order bits and the remaining bits called the rest field, host identifier, or interface identifier (IPv6),

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An IPv4 address has a size of 32 bits, which limits the address spaceto 4294967296 (2 ) addresses. Of this number, some addresses

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IP addresses are assigned to a host either dynamically as they join the network, or persistently by configuration of the host hardware or software.

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IP addresses are classified into several classes of operational characteristics: unicast, multicast, anycast and broadcast addressing.
Unicast addressing
The most common concept of an IP address is in

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In IPv6, the address size was increased from 32 bits in IPv4 to 128 bits, thus providing up to 2 (approximately 3.403×10 ) addresses. This is deemed sufficient for the foreseeable future.

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