Introduction to IPv6 (Internet Protocol Version 6)

What is IPv6?

Internet Protocol Version 6 (IPv6) is a network layer protocol that enables data communications over a packet switched network. Packet switching involves the sending and receiving of data in packets between two nodes in a network. 

It has primarily been developed to solve the problem of the eventual exhaustion of the IPv4 address

space, but also offers other enhancements. IPv6 addresses are 16 bytes long, in contrast to IPv4’s 4 byte addresses.

The working standard for the IPv6 protocol was published by the Internet Engineering Task Force (IETF) in 1998.
The IETF specification for IPv6 is RFC 2460. IPv6 was intended to replace the widely used Internet Protocol Version 4 (IPv4) that is considered the backbone of the modern Internet. IPv6 is often referred to as the "next generation Internet" because of it's expanded capabilities and it's growth through recent large scale deployments. In 2004, Japan and Korea were acknowledged as having the first public deployments of IPv6.

The explosive growth in mobile devices including mobile phones, notebook computers, and wireless handheld devices has created a need for additional blocks of IP addresses. IPv4 currently supports a maximum of approximately 4.3 billion unique IP addresses. IPv6 supports a theoretical maximum of 2¹²⁸  addresses (340,282,366,920,938,463,463,374,607,431,768,211,456 to be exact!). Recent advancements in network technology including Network Address Translation (NAT) have temporarily lessened the urgency for new IP addresses, however, recent estimates indicate that IPv4 addresses could be exhausted as soon as 2012.

IPv6 versus IPv4

IPv6 and IPv4 share a similar architecture. The majority of transport layer protocols that function with IPv4 will also function with the IPv6 protocol.

- IPv4 addresses 2³²  = 4,294,967,296

- IPv6 addresses 2¹²⁸= 340,282,366,920,938,463,463,374,607,431,768,211,456

- 340 undecillion –US, 340 sextillion-UK

- 79,228,162,514,264,337,593,543,950,336 times more v6 addresses than v4

- If IP addresses weighed one gram each–IPv4 = 1/7th of the Empire State Building

- IPv6 = 56 billion(US) earths

- Uncontrolled fragmentation in IPv4

       –Only a source node can fragment IPv6

       –Limits packet size to minimum MTU in path (Maximum Transmission Unit)

-autoconfiguration of addresses by hosts

Features of IPv6

•Addressing

•Header

•Security

•Privacy

•Autoconfiguration

•Routing

•Quality of Service

->Expanded addressing and routing capabilities
     –128-bit addresses
     –Multicast routing is now scalable with “scope” field
     –Defined usage of “Anycast” addressing

Challenges in today's Internet

-> Address depletion 

-> Loss of peer-to-peer model

-> Increasing need for Security

-> Burdened Infrastructure

-> Increasing need for IP mobility

-> Increased traffic flow 

-> New applications have specific delivery requirements 

-> Increasing need for security and information protection

-> Varied usage of Internet requires continual "tweaking" of current Internet Protocols

-> IPv4 growth and adoption phenomenal
        –Exhausting address space
        –Internet routing table very big
-> IPv4 Lack of inherent features
        –Quality of Service (QoS)
        –Security
-> IPv4 failings
        –Broadcast
        –Uncontrolled Packet Fragmentation
-> Security
        –No uniformity, myriad methods
        –Multitude of methods for “hackers” to attack networks

 -> Mobility
     –Increasing number of wireless/mobile devices accessing Internet services
     –Inadequate support for IP mobility in devices (moving seamlessly from one network to another)
     –3G & 4G initiatives, 802.11x, Bluetooth, UWB moving connectivity from wireline to wireless


This is All about the introduction to IPv6. Now in my next post i will explain the features and more about IPv6.....