IPv6

IPv6 (Internet Protocol Version 6) is the version of internet protocol which supports the 128-bit IP addresses. It has been developed as the next generation protocol to increase the 4 billion IP Addresses available and it will eventually replace the nearly exhausted IPv4, which supports 32-bit address space. IPv6 has been developed to provide advantages over the current internet protocol. It is expected to solve several network problems by eliminating the need for Network Address Translation (NAT).

Background

As early as 1990, internet experts predicted that the 4 billion available IP addresses under the IPv4 were not enough to accommodate the rapid growth of internet users worldwide. During the Internet Engineering Task Force Meeting (IETF) in Vancouver in 1990, Phil Gross, Chairman of the Internet Steering Group (IESG), together with Frank Solensky and Sue Hares, informed that the Class B space will be exhausted as early as March, 1994. The solution to the problem was to assign multiple Class C address.This expansion signaled a great problem, which meant deciding whether to limit the size and growth rate of the internet or to disrupt the network by changing to new strategies or technology.

In 1991, the Internet Architecture Board (IAB) recommended the need for additional address flexibility. Based on this recommendation, the Internet Engineering Task Force formed the Routing and Addressing (Road) Group to examine the consumption of address space and the exponential growth in inter-domain routing entries. The Road Group enumerated three possible serious problems, which include:Exhaustion of the class B network address space, Growth of routing tables in Internet routers beyond the ability of current software, hardware, and people to effectively manage it, and eventual exhaustion of the 32-bit IP address space. It also recommended immediate and long term solutions which include the adoption of CIDR route aggregation proposal, reducing the growth rate of routing table and called for proposals "to form working groups to explore separate approaches for bigger Internet addresses."

In 1993, IETF formed the Internet Protocol Next Generation Group to evaluate the proposals and determine how to proceed in selecting a successor to the IPv4. THe group evaluated and reviewed the proposals of CATNIP, SIPP and TUBA. After numerous discussions, the Directorate recommended the adoption of Simple Internet Protocol Plus (SIPP) Spec. (128 bit version as the basis for the next generation of Internet Protocol. The version number 6 was assigned by IANA and it was officially called IPv6.

IPv6 Working Group

The IPv6 Working Group was created by the IESG as to implement the recommendations of the Internet Protocol Next Generation's Directors set forth during the IETF meeting in July, 1994 as described in RFC 1752 entitled, The Recommendation for the IP Next Generation Protocol. The IPv6 working group's primary role is to oversee the specification and standardization of IPv6.

IPv6 Features & Benefits

IPv6 has the following features and benefits:

1. Expanded addressing capabilities of 128 bits, a larger number of addressing nodes and a simpler auto configuration of addresses.
2. Simplified header for routing efficiency and performance
3. Improved Support for Extensions and Options
4. Flow Labeling Capability
5. Authentication and Privacy Capabilities
6. Deeper hierarchy and policies for network architecture flexibility
7. Efficient support for routing and route aggregation
8. Server less autoconfiguration, easier renumbering, multihoming, and improved plug and play support
9. Security with mandatory IP Security (IPSec) support for all IPv6 devices
10. Improved support for Mobile IP and mobile computing devices (direct-path)
11. Enhanced multicast support with increased addresses and efficient mechanism

IPv6 Address Notation

An IPv6 address is written in hexadecimal quartets separated by colon for example: 2001:cdba:1900:0000:0000:0000:1757:3618 If there is a four-digit group of zeroes within an IPv6 address, it can be reduced to a single zero and delete the group of 4 zeroes and the address can be written as:2011:cdba:1900:0:0:0:1757:3818 or 2001:cdba:1900:3257:9652

Types of IPv6 Addresses

IPv6 has three types of addresses, which include:

• Unicast Address, which serves as a single interface identifier and it is delivered to the interface identified by the address;
• Multicast Address, an identifier for a group/set of interfaces that may belong to the different nodes delivered to multiple interfaces
• Anycast Address, an identifiers for a set of interfaces that may belong to different nodes and it is delivered to any of the interfaces identified by the address.

IPv6 Special Addresses

The next generation Internet Protocol version 6 has special addresses, which include:

• ::/96 -is a zero prefix denoting the addresses compatibility with the previously used IPv4 protocol.
• ::/128 -is an IPv6 address with all zeroes in and is referred to as an unspecified address and is used for addressing purposes within a software.
• ::1/128 -referred as loop back address and is used to refer to the local host. An application sending a packet to this address will get the packet back after it is looped back by the IPv6 stack. The local host address in the IPv4 was 127.0.0.1.
• 2001:db8::/32 -is the official documentation prefix allowed by IPv6 which denotes that the address is only an example
• fec0::/10 -is a site-local prefix offered by IPv6 which implies that the address is valid only within the local organization.The use of this prefix is discouraged by RFC
• fc00::/7 -referred as the Unique Local Address, which are routed only within a set of cooperating sites. It was introduced to replace the site-local addresses and provides a 40-bit pseudorandom number which lessens the risk of address conflicts.
• ff00::/8 -is a prefix used to automatically denote a multicast address
• fe80::/10 -is a link-local prefix offered by IPv6 signifying that the address is valid only in the local physical link.

IPv6 Forum

On July 17, 1999, the IPv6 Forum, a non-profit organization was established composed of international Internet vendors, Industry Subject Matter Experts, Research & Education Networks to help educate and inform the global internet community regarding the importance of deploying the IPv6.

IPv6 Deployment

Om December 1995, IANA formally assumed the responsibility of the address management functions of IPv6 subsequently in 1996, the IPv6 standard is completed and its production allocation is made available to ISPs in 1999. The early phase of IPv6 deployment started in 2000 using tunneling techniques over a common IPv4 layer.Google and Comcast are among the large internet operators deploying IPv6. By mid 2007, public interest on the use of IPv6 increased based on the Autonomous System (AS) routing table. Between 2004 to 2008, IPv6 routes increased from 2.5 % TO 3%. iN 2008, the size of IPv6 deployment in terms of host capability is between 2-3 per one thousand internet hosts.

Google Experiment on IPv6

The experiment conducted by Google on IPv6 end-user connectivity and traffic levels in 2009 found that:

• 0.25% of users were IPv6 capable as September 2009 and half of the users were using MacOs and Windows Vista
• 0.9% of end-users using other technically oriented websites were connected to IPv6 when possible as of June 2009
• Leading countries countries capable of using IPv6 as of September 2009 were France (1%), China (0.4%), Sweden (0.2%), Japan, Netherlands and United States (less than 0.1%)
• networks originating majority of IPv6 traffic come from universities and research institutions with the exemption of free.fr, a French IPv6 enabled ISP.

ICANN's IPv6 Global Allocation Policy

On July 16, 2006, ICANN released its' policy statement regarding the allocation of IPv6 address space which include:

• The unit of IPv6 address space allocation from IANA will be /12. A sufficient number of address space will allocated to every RIR to support their registries needs for 18 months.RIR will be responsible in choosing their own allocation reservation strategies to ensure effective and efficient work.
• Every RIR with less than /12 of un-allocated address space will receive an IPv6 allocation from IANA following ICANN's implementation of the IPv6 Address Space Global Allocation Policy.
• Any RIR will be eligible for an additional allocation of IPv6 address space if an RIR has less than 50% of the /12 and an RIR's IPv6 address space is less than its established necessary space for the next 9 months period. During this situations, IANA will make a single IPv6 allocation enough to meet the RIR's established address space for 18 months.
• The IPv6 necessary space will be calculated this way, NECESSARY SPACE=AVERAGE NO. OF ADDRESSES ALLOCATED PER MONTH x LENGTH OF PERIOD IN MONTHS
• The allocation of IPV6 addresses to an RIR should be announced an updated on IANA, National Resource Organization (NRO), the coordinating body for the 5 RIRs responsible in distributing IP addresses and AS numbers; and RIR respective websites. The administrative procedures to manage this process will be handled by ICANN and NRO.