IPv4 to IP6 Transition - part 1

According to the issues being discussed so much that the IPv4 which is the foundation of the Internet has nearly approaching the ultimate limit of his ability.It will be a transition mechanism from IPv4 to IPv6 model which is a new protocol has been designed to be able to replace the function of IPv4. The main motivation for the change is due to the limitations of IPv4 addresses that long only 32 bit only and are not able to support the need for secure communications, flexible routing and traffic regulation data.

IP version 6 (IPv6) is a new version of Internet protocol that is designed as the successor of Internet protocol version 4 (IPv4) which is defined in RFC 791. IPv6 address that has a huge capacity (128 bits), supporting the preparation of a structured addressing, which allows the Internet continues to evolve and provide new routing capabilities which not found in IPv4. The anycast address of IPv6  has a type that can be used to efficiently route selection. IPv6 is also supplemented by mechanisms address utilization locally which allows the realization of the installation is Plug & Play, as well as provide a platform for new ways of using the Internet, such as support to the flow of data in real-time, the selection of providers, mobility of hosts, end-to-end security, or automatic configuration.


The Advantages of IPv6

1.  Automation of the various settings

Automation of the various settings / Stateless-less auto-configuration (plug & play) on the IPv4 Address to host essentially static. Usually administered sequentially on the host. It is now can be done automatically by using DHCP (Dynamic Host Configuration Protocol), but it is on IPv4 only an additional function, otherwise the function for setting up IPv6 automatically provided by default. In this automatic setting, there are 2 ways depending on the use of address, namely stateless and statefull automatic settings.

• Automatic Statefull Settings
  Automatic Statefull Settings is the way the management of strictly in terms of range of IP addresses provided on the host by providing a server for state management IP address, which means it is almost similar to the way DHCP in IPv4. At the time of doing the settings automatically, the information required between routers, servers and hosts are ICMP (Internet Control Message Protocol) which has been expanded. In the ICMP in IPv6, including the IGMP (Internet Group Management Protocol) used on multicast in IPv4.

• Stateless Auto setting

Stateless Auto setting  does not need to provide a server for managing and sharing an IP address, just setting up the router is just where the host has been connected in a network of routers that exist on the network prefix of the address obtained from the network. Then the hosts increase the bit pattern obtained from the information that is unique to the host, then create a 128-bit IP address and making it an IP address from that host. On information unique to this host, used among other MAC addresses of network interfaces. In this stateless automatic setting behind the ease of management, on an Ethernet or FDDI because of the need to give at least 48 bits (by MAC address) against one network, has the disadvantage of a bad address utilization efficiency.

2. Address  Capacity Expansion

IPv6 increases the size and number of addresses that can be supported by IPv4 from 32 bit to 128bit. Increasing the capacity of these addresses are used to address capacity can be allocated and administered in the nodes and simplify configuration on the node address so it can be done automatically. Improved scalability of multicast routing is also done in by increasing the scope and number of the multicast address. IPv6 addresses in addition to increasing the amount of capacity that can be allocated on the node is also introducing a new address type or types, in example anycast address. Anycast address type is defined and used to send packets to one of a collection of nodes.

3. Header Format Simplification

Some of the fields in IPv4 header has been removed or to be created as a header option. It's used to reduce the cost of processing the things common to the handling of IPv6 packets and limit the cost of bandwidth in IPv6 header. Thus, the IPv6 packet header processing can be done efficiently.

4. Options and Extension Headers

It's changes that occur in IP headers that is the presence of encoding header Options (option) on the IP entered to be more efficient in forwarding packets (packet forwarding), so as not to be too strict in limiting the length of the header options contained in the IPv6 packet and highly flexible / possible to introduce a new option header in the future.

5. Flow Labeling Capability Package

Capabilities or new features added to IPv6 is that it allows package labeling or classifying packets that require special handling, such as the quality of a certain quality of service (QoS) or real-time.

6. Authentication and Privacy Capabilities

Additional capabilities to support authentication, data integrity and critical data are also specified in the IPv6 address. The biggest change in IPv6 is the expansion of the IP address of 32 bits in IPv4 to 128 bits.
The 128 bit address space which is continuous by eliminating the concept of class. It also made ​​changes to the way of writing the IP address. If the IPv4 32 bits divided into 8 bits each of which separated it with "." and written as a decimal, then on IPv6, 128 bits are separated into each of 16 bits each section separated by ":" and written with a hexadecimal. In addition it also introduced tiered structure to manage the routing becomes easy. In CIDR (Classless interdomain routing) routing table is minimized by combining into one routing information of an organization.