The evolution of various wireless technologies has greatly increased the interest in heterogeneous networks, in which the mobile users can enjoy services while roaming between different networks. The current Internet architecture does not seem to cope with the modern networking trends and the growing application demands for performance, stability and efficiency, as the integration of different technologies faces many problems. In this paper, we focus on the issues raised when attempting to provide seamless mobility over a hybrid environment. We highlight the shortcomings of the current architecture, discuss some of the proposed solutions and try to identify the key choices that lead to failure. Finally, we introduce RINA (Recursive Inter-Network Architecture), a newly-proposed network architecture that achieves to integrate networks of different characteristics inherently and show a simple example that demonstrates this feature.