Internet Protocol version 6 (IPv6) is the new version
of the Internet Protocol (IP). The Internet Protocol allows numerous
nodes on different networks to interoperate seamlessly. Internet Protocol
version 4 (IPv4) is currently used in intranets and private networks,
as well as the Internet. IPv6 is the successor to IPv4, and is based
for the most part on IPv4.
IPv4 has been widely deployed and used to network
the Internet today. With the rapid growth of the Internet, enhancements
to IPv4 are needed to support the influx of new subscribers, Internet-enabled
devices, and applications. IPv6 is designed to enable the global expansion
of the Internet.
IPv6 builds upon the functionality of IPv4, providing
improvements to addressing, configuration and maintenance, and security.
IPv6 offers the
Expanded addressing capabilities—IPv6 provides a
larger address space. IPv6 addresses consist of 128 bits, while IPv4
addresses consist of 32 bits. 128-bit addressing increases the
address space by approximately 1029 unique addresses, enough to last
for the forseeable future.
Header format simplification—IPv6 packet header
format is designed to be efficient. IPv6 standardizes the size of
the packet header to 40 bytes, divided into 8 fields.
Improved support for extensions and options—Extension
headers carry Internet-layer information and have a standard size
Flow labeling capability—Flow labels provide consistent
handling of packets belonging to the same flow.
Improved privacy and security—IPv6 supports extensions
for authentication and data integrity, which enhance privacy and security.