IPV 6

Internet Protocol version 6, is a new addressing protocol designed to incorporate whole sort of requirement of future internet known to us as Internet version 2. This protocol as its predecessor IPv4, works on Network Layer (Layer-3). Along with its offering of enormous amount of logical address space, this protocol has ample of features which addresses today’s shortcoming of IPv4.

Why new IP version?

So far, IPv4 has proven itself as a robust routable addressing protocol and has served human being for decades on its best-effort-delivery mechanism. It was designed in early 80’s and did not get any major change afterward. At the time of its birth, Internet was limited only to a few Universities for their research and to Department of Defense. IPv4 is 32 bits long which offers around 4,294,967,296 (232) addresses. This address space was considered more than enough that time. Given below are major points which played key role in birth of IPv6:

Internet has grown exponentially and the address space allowed by IPv4 is saturating. There is a requirement of protocol which can satisfy the need of future Internet addresses which are expected to grow in an unexpected manner.

Using features such as NAT, has made the Internet discontiguous i.e. one part which belongs to intranet, primarily uses private IP addresses; which has to go through number of mechanism to reach the other part, the Internet, which is on public IP addresses.

IPv4 on its own does not provide any security feature which is vulnerable as data on Internet, which is a public domain, is never safe. Data has to be encrypted with some other security application before being sent on Internet.

Data prioritization in IPv4 is not up to date. Though IPv4 has few bits reserved for Type of Service or Quality of Service, but they do not provide much functionality.

IPv4 enabled clients can be configured manually or they need some address configuration mechanism. There exists no technique which can configure a device to have globally unique IP address.

Depleted IPv4 addresses are not enough for many enterprises to deploy IPv6. Use of these IPv6 benefits to make a business case for your IPv6 migration.

IPv6 (Internet Protocol version 6) is a set of specifications from the Internet Engineering Task Force (IETF) that's essentially an upgrade of IP version 4 (IPv4). The basics of IPv6 are similar to those of IPv4 -- devices can use IPv6 as source and destination addresses to pass packets over a network, and tools like ping work for network testing as they do in IPv4, with some slight variations.

The most obvious improvement in IPv6 over IPv4 is that IP addresses are lengthened from 32 bits to 128 bits. This extension anticipates considerable future growth of the Internet and provides relief for what was perceived as an impending shortage of network addresses. IPv6 also supports auto-configuration to help correct most of the shortcomings in version 4, and it has integrated security and mobility features.

IPv6 features include:

• Supports source and destination addresses that are 128 bits (16 bytes) long.
• Requires IPSec support.
• Uses Flow Label field to identify packet flow for QoS handling by router.
• Allows the host to send fragments packets but not routers.
• Doesn't include a checksum in the header.
• Uses a link-local scope all-nodes multicast address.
• Does not require manual configuration or DHCP.
• Uses host address (AAAA) resource records in DNS to map host names to IPv6 addresses.
• Supports a 1280-byte packet size (without fragmentation).
• Moves optional data to IPv6 extension headers.
• Uses Multicast Neighbor Solicitation messages to resolve IP addresses to link-layer addresses.
• Uses Multicast Listener Discovery (MLD) messages to manage membership in local subnet groups.
• Uses ICMPv6 Router Solicitation and Router Advertisement messages to determine the IP address of the best default gateway