IPv6 Transition Technologies (and co-existence technologies) allow organizations to migrate from IPv4 to IPv6 smoothly.

Unless we’re running a small network, when we transition from IPv4 to IPv6 we’ll need to migrate our network area by area. These IPv4 areas and IPv6 areas need to seamlessly work with each other. We also may need to communicate with a network outside of our organization that is using a different Internet Protocol version. IPv4 and IPv6 must be able to co-exist.

Before discussing transition/co-existence technologies we need to consider node types and ways to network these node types.

Node Types

There are three node types:

  •  IPv4 – Supports IPv4 only
  •  IPv6 – Supports IPv6 only
  •  IPv4/IPv6 – Supports both IPv4 and IPv6

The possible combinations that the nodes types can be networked together are:

  •  IPv4>IPv6
  •  IPv6>IPv4
  •  IPv4>IPv6>Ipv4
  •  IPv6>IPv4>IPv6
  •  IPv4/IPv6 > IPv4/IPv6

Transition/Co-existence Categories

There are three categories of transition/co-existence technologies:

  • Dual Stack
  • Translation
  • Tunneling

Choosing the correct category of transition/co-existence technologies depends on the combination of node types that will be handling the traffic.

Dual Stack

IPv4/IPv6 > IPv4/IPv6: Both devices run Dual Stack - both IPv4 and IPv6 run independently and in parallel. Either IP can be used. Both devices are “bi-lingual”

Ultimately, the goal is to transition a network to IPv6 by running Dual Stack throughout the entire network, then carefully removing IPv4 until only IPv6 is left. Since this is done area by area, Tunneling and Translation technologies are needed until Dual Stack or IPv6-only can be implemented.


IPv4>IPv6: IPv4 is Translated to IPv6
IPv6>IPv4: IPv6 is Translated to IPv4
These two nodes could be on the same link or go through routers that are running IPv4 and IPv6 simultaneously.


IPv4>IPv6>IPv4: IPv4 is Tunneled through IPv6
IPv6>IPv4>IPv6: IPv6 is Tunneled through IPv4


This lesson provided an introduction to IPv4 and IPv6 Transition/Co-existence technologies.

In the next lessons, we’ll take a closer look at Dual Stack, Tunneling and Translation techniques.

Related Lessons

To continue reading, please login or become a member for full access...