Internet is growing every day and this is leading to an address depletion of the current IPv4 addresses. A new version of IPv4, called IPv6, is the protocol for addressing computers that will deal with this problem. IPv4 and IPv6 are unfortunately not compatible with each other. IPv4 and IPv6 have to co-exist for a long time until IPv6 will be the dominant protocol.

The purpose of this thesis is to examine how a transition could be done or more correctly, how to deploy IPv6 in an already existing IPv4 network. After that part of the report a case study at the local Internet service provider Junet AB will be conducted. This case study will investigate an IPv6 deployment scenario for Junet AB.

A theoretical background has been written that describes some steps an Internet service provider has to go through to deploy IPv6. The case study was conducted after the theoretical background was written. The result of this report shows that a deployment of IPv6 in an IPv4 network is technically achievable. All the main components to maintain and use IPv6 in a commercial network exist.

The case study indicates that it is possible to deploy IPv6 in Junet AB´s network. IPv4 and IPv6 could be used in their network without any major effort. IPv6 have been around for many years now but have not had that break through many early adopters have hoped for. A lack of documentation and experience is an obstacle for a deployment of IPv6.One thing that remains now is to prove that there is a need for IPv6, but that is out of scope for this thesis.