There are fields in the IPv4 header that maintain their function in the IPv6 header, but with a different name. Some examples are the field ‘TTL’, that is now replaced by ‘Hop Limit’ or the field Protocol, which function is absorbed in a more efficient way by the field ‘Next header’.

Although it is true that some fields of the IPv4 header remain for the new IP protocol version, others have also been added to accomplish new functionalities. Particularly the field that enables the identification of IP flows, named flow label, which opens new possibilities for the handling of QoS over Internet.

The IPv6 Task Force are working groups that coordinate actions to achieve IPv6 development inside the region or country where it is established. In the world there are more than 35 IPv6 Task Forces created for this purpose.

In order to represent IPv6 address in the Domain Name System, it is used a new type of Record named AAAA or quad A. This type of Record coexist in zone file with the other types of Records (MX, A, CNAME, etc).

IPv6 was conceived with the idea of coexistence with IPv4 for a large period... That is why, there is no "migration" date, or D day, but only a transition mechanism that allows both protocols to coexist. There are, for this purpose, more than 40 transition mechanisms proposed at the IETF. This is only a matter of choosing the more convenient to our needs.

Inverse resolution for IPv6 address is done in a new hierarchic named ipv6.arpa, using the same PTR registries as in IPv4. Previously, it was proposed to use the ip6.in structure, but currently this was substituted.

In IPv6 mobility does not have the problem of unbalanced routing as like in IPv4 packages, so that a mobile connection is so efficient as a normal connection. This is due to there is a process through which the mobile node can inform the node which communicates to which is the address in the new network and use this address for their communication.

The mobility feature is included in the design of the IPv6 protocol, by which a mobile node does not need special features on the visiting network to be able to use it. In this way the mobile node could connect to different networks maintaining active their connections and continuing at a transparent way with the applications that were using.

Con IPv6 podemos asignar mútliples direcciones a una misma interfaz y múltiples prefijos a un mismo enlace. Dentro de lo especificado en el protocolo todas estas direcciones y prefijos pueden ser de cualquier tipo y/o ámbito...