What is IPv6 (Internet Protocol Version 6)?

IPv6 is the newest version of the IP protocol. IPv6 was developed to overcome many deficiencies of IPv4, most notably the problem of IPv4 address exhaustion. Unlike IPv4, which has only about 4.3 billion (2 raised to power 32) available addresses, IPv6 allows for 3.4 × 10 raised to power 38 addresses.

IPv6 features

Here is a list of the most important features of IPv6:

  • Large address space: IPv6 uses 128-bit addresses, which means that for each person on the Earth there are 48,000,000,000,000,000,000,000,000,000 addresses!
  • Enhanced security: IPSec (Internet Protocol Security) is built into IPv6 as part of the protocol . This means that two devices can dynamically create a secure tunnel without user intervention.
  • Header improvements: the packed header used in IPv6 is simpler than the one used in IPv4. The IPv6 header is not protected by a checksum so routers do not need to calculate a checksum for every packet.
  • No need for NAT: since every device has a globally unique IPv6 address, there is no need for NAT.
  • Stateless address autoconfiguration: IPv6 devices can automatically configure themselves with an IPv6 address.

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