ENST Bretagne We propose an architecture for the support of IPv6 over cellular mobile networks. The architecture is adapted to the characteristics of global cellular systems offering connectivity to very large numbers of subscribers (e.g. 3GPP). We are also concerned with particularities of the cellular air interfaces. The architecture takes in consideration mobile IPv6 terminals. Finally, it gives a way of protection of the available network resources and of the subscribers confidentialities with an on demand security mechanism.