Differences Between Internet Protocol Version 4 (IPv4) and Internet Protocol Version 6 (IPv6)

IPv4 has been in use as the predominant protocol on the Internet for nearly three decades. It was originally defined in 1981 in a technical specification known as RFC 791. IPv4 is a connectionless protocol that operates at the Network Layer (Layer 3) of the OSI model. IPv4 is the foundation of the TCP/IP protocol suite as it exists today.

IPv4 was designed with several assumptions in mind, many of which have been proved inaccurate, grossly overestimated, or simply nonapplicable. While IPv4 has been the predominant protocol on the Internet, a replacement is long overdue. Some of the key issues of concern are exhausted address space of only 32 bits, ...

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