If IP works so well, why a need is felt to change The primary motivation for change arises from the limited address space. When IP was defined, only a few compute networks existed. The designers decided to use 32 bits for an IP address because doing so allowed the Internet to include over a million networks. However, with a rapid exponential growth in the global Internet, the primary motivation for defining a new version of IP arose from the address space limitation, as larger addresses are necessary to accommodate continued growth of the Internet. Besides addressing, the most common problems faced by the TCP/IP were routing and connectivity issues.
Secondary motivations for changes in IP have risen from new Internet applications. For example, applications that deliver audio and video need to deliver data at regular intervals. To keep such information flowing through the Internet without disruption, IP must avoid changing routes frequently. Although the current IP datagram header includes a field that can be used to request a type of service, the protocol did not define a type of service that can be used for real-time delivery of audio and video. New applications are being developed that require more complex addressing and routing capabilities. Thus, a new version of IP needs to include mechanisms that make addressing and routing possible. (Douglas)
The current version of IP, which possesses the main drawback of address space, routing and connectivity, is version 4 so it is referred to as Ipv4. Ipv6 is the official name of IPng (Internet Protocol next generation)
Features of Ipv4 and Ipv6
1. Connectionless - each datagram contains a destination address, and each datagram is routed independently.
2. The header in a datagram contains a maximum number of hops the datagram can take before being discarded.
3. Ipv4 places key information in fixed fields of the header and only appends variable-length options for less important information while Ipv6 header is always of variable size.
Reasons for changing Ipv4 to Ipv6
Larger and better Network management of Address Space:
The most considerable reason for the decision of changing from Ipv4 to Ipv6 is the smooth management of the IPv6 network. As the answer to the lack of address space, IPv6 holds a potential for a network the size of which has never been seen before. The manner in which the network is managed will to a great extent determine whether this huge network will function. The main objectives, which are visualized in network management, would be:
1. Display the distinct hierarchy embedded in the IPv6 address architecture,
2. Show topographical data simultaneously to the hierarchy,
3. Make peripheral data easily available, and
4. In doing so, aid in the process of network management.
Ipv6 research and ideology basically revolves around network management. This is because most of the problems in IPv4, which IPv6 is created to