IPv6

If there is anything that can be placed after food, air, and water, it is Internet. The number of computers connected to the internet has become directly proportional to the services that are deployed over networks.

What is IP Address?
Like every element in this universe, every computer has a unique identity. And the identity of every computer is determined by a unique Internet Protocol (IP) address assigned to it. The version of IP that was widely deployed was IPv4; the 4^th version in the development of IP. It is usually referred to as the backbone of modern Internet.

IPv4 has exhausted!

The use of Internet for computers, sensors, telephones, kitchen appliances, remote medical assistance, education, transportation, etc., has been growing exponentially. And this very factor has marked the exhaustion of the IPv4 IPs.

An announcement by the Number Resource Organization (NRO), on 3rd February 2011, clarified that the free pool of available IPv4 addresses has fully depleted. The Internet Assigned Numbers Authority (IANA) allocated the remaining IANA pool equally between the five RIRs (Regional Internet Registries). Although the complete extinction of IPv4 has not yet occurred, adaptation of IPv6 is vital for all Internet stakeholders.

What is IPv6?

IPv6 is the latest version of the Internet Protocol that has been designed as a replacement for IPv4. IPv6 is usually known as the Internet’s next-generation protocol.

How is IPv6 Better than IPv4?

IPv6 betters IPv4 in the following respects:

Large Address Space

With the growing number of mobile phones, PDAs, laptops, handheld devices, etc., additional blocks of IP addresses need to be created. And IPv4 cannot carry out this job. This is where IPv6 comes as a relief.

IPv6 increases the IP address size from 32 bits to 128 bits, thereby increasing the number of globally routable IP addresses, from approximately 4.29×10⁹ = 4.2 billion to 3.4×10³⁸ = 340 trillion trillion trillion addresses. Theoretically, IPv6 can provide 3.4×10³⁸ / 7×10⁹ (i.e. population on earth) = 4.86×10²⁸ IP addresses per person on earth.

Security
Unlike devices with IPv4, those with IPv6 can establish a secure pipeline between them without user intervention. This is possible because IPv6 has a built in IPSec support which can negotiate security parameters dynamically.

Mobility
The Mobile IPv6 (MIPv6) offers roaming capabilities for mobile nodes in IPv6 network. This allows mobile devices, such as PDAs and smart phones, to change the wireless networks without breaking their connections.

The MIPv6 allows devices to move geographically without changing the IPv6 address assigned to it.

Simplified network configuration (Auto-configuration)

Similar to IPv4, IPv6 supports stateful auto-configuration to assign IP address to a computer using Dynamic Host Configuration Protocol for IPv6 (DHCPv6).

To make the network configuration more simplified, IPv6 supports stateless auto-configuration. In this, no server is required to obtain configuration information, and router advertisements are used to create addresses. This creates a “plug-and-play” environment thus, simplifying management and administration.

IPv6 also allows automatic address configuration and reconfiguration, and administrators do not require access to the clients to renumber network addresses.

QoS (Quality of Service)

IPv6 ensures improved quality of service because it helps in identifying traffic and defines how it should be handled. This is ensured by the Flow Label field in the IPv6 header. Packets that belong to this flow are easily identified by routers and are specially handled.

Extensibility
IPv6 is designed to have an optional header separate from the main IPv6 header. This allows the protocol to be extensible in the future which offers optimized support for new features without redesigning the IPv6 protocol.

 More Efficient Routing
IPv6 is better than its predecessor IPv4 in that it makes routing more efficient and hierarchical. This is done by shrinking the size of routing tables. Internet Service Providers assign prefixes to their customers’ network. With the help of IPv6, they can aggregate all such prefixes into a single prefix, and announce the same to the Internet Protocol.

End-to-end transparency

Thanks to the vast address space, a computer with IPv6 can stay in peer-to-peer connection with another computer. This very feature helps enabling new and valuable services. Services like VoIP and QoS will become more robust, as they are easier to create and maintain.

The only question that remains is – When and how to manage the migration from IPv4 to IPv6 without affecting existing services?

The transition from IPv4 to IPv6 is currently happening but with a gradual pace. There is also a degree of uncertainty over the adoption of IPv6 standards and implementation. Although the transition will not be effortless, formulating plans by Internet stakeholders, engineers, and government bodies will boost the migration.