Cross-layer design in vertical handoff technique

In next generation network (NGN), different access networks are integrated and seamless vertical handoff technique should be performed. Cross-layer design for vertical handoff has gained considerable attention in recent years. In this paper, we give a survey on cross-layer strategy in vertical handoff scheme design including both cross-layer system architectures and cross-layer information interaction mechanisms for handoff performances improvement in heterogeneous integration networks. Furthermore, we point out some open technical challenges in the cross-layer design for seamless integration of heterogeneous networks.