What is IPv6?
IPv6 is the next generation of IP addressing or Internet Protocol. The previous version of IP addressing (IPv4) is depleted or near depletion.
IPv6 was created by the Internet Engineering Task Force (IETF), a standards body, as a replacement to IPv4 in 1998.
However, IPv6 is equipped with so much improved features and limitless opportunities more than IPv4. This next generation of IP addressing boasts of increased security and more IP addressing space.
IPv6 predecessor (IPv4) uses 32 bits for addressing. It provides approximately = 4,294,967,296 unique addresses – about 3.7 billion addresses are assignable or routable on the internet.
IPv6 is equipped with 128 bits for addressing. This provides approximately 3.4 x 1038 addresses. This runs into trillions for every individual on the planet! That’s a hell of a huge number of IP addresses. We will look at it in detail later on.
The most important feature offered by IPv6 is the address auto-configuration. This feature supports fast connectivity for any combination of computers, printers, digital cameras, digital radios, IP phones, and Internet-enabled household appliances, to be connected to their home networks.
In a nutshell, these devices on the network automatically address themselves with a link-local unicast address.
The auto-configuration mechanism was introduced to enable plug-and-play networking of these devices to help reduce administration overhead.
Other Improved Features of IPv6.
Many of the improvements that IPv6 offers are, including:
• Superior IP addressing
• Simplified header
• Mobility and security
Superior IP Addressing: A larger address space offers several improvements, which include global connectivity and flexibility. It also offers more plug-and-play options for more devices and auto-configuration that can include Data Link layer addresses in the address space..etc.
Simplified header: The IPv6 simplified header offers several advantages over IPv4, this includes:
• IPv6 offers better routing efficiency for performance.
• Elimination of broadcasts and thus no potential threat of broadcast storms (uses multicast traffic instead)
• No requirement for processing checksums.
• Simplified and more efficient extension header mechanisms.
Improved Features of IPv6:
Mobility and security help ensure compliance with consumers’ mobile IP and IP Security (IPsec) standards functionality. Mobility enables people with mobile network devices, many with wireless connectivity, to move around in networks.
However, IPsec is available for both IPv4 and IPv6. Its functionalities are identical in both internet protocols, IPsec is mandatory in IPv6, making the IPv6 Internet more secure.
Summary of Transitioning to IPv6
■ IPv6 offers many additional benefits to IPv4, including a larger address space, easier address aggregation, and integrated security.
■ The IPv6 address is 128 bits long and is made up of a 48-bit global prefix, a 16-bit subnet ID, and a 64-bit interface identifier.
■ There are several ways to assign IPv6 addresses—statically, stateless autoconfiguration, and DHCPv6.
■ Cisco supports all the major IPv6 routing protocols—RIPng, OSPFv3, and EIGRPv6.
■ Transitioning from IPv4 to IPv6 requires dual stacks, tunnelling, and possibly NAT-PT.
■ Use the ipv6 unicast-routing command to enable IPv6 and the ipv6 address ipv6-address/prefix-length command to assign interface addresses and enable an IPv6 routing protocol.
How to Configure IPv6 on Cisco Routers
