In the past, our proposed HCoP-B has achieved route optimization and resolved the RO-storm problem for handoffs of the nested mobile network. However, because HCoP-B is a pure layer three, i.e., network layer, approach which handoff operations are performed after the layer two, i.e., data link layer, link breaks, it still suffers from a long handoff latency and serious packet losses. In this paper, by adopting the handoff prediction concept of the fast mobile IPv6 on HCoP-B, our cross-layer architecture, which is called the fast HCoP-B (FHCoP-B), can trigger HCoP-B layer three route optimization flow by 802.11 and 802.16 link events before the actual Layer 2 handoff occurs. In this way, FHCoP-B further shortens both the handoff latency and packet losses of HCoP-B.

By adopting the handover prediction concept of the fast mobile IPv6 on HCoP-B, we have proposed the predictive fast HCoP-B (FHCoP-B) architecture, which could trigger the layer three route optimization flow of HCoP-B early enough by useful layer two 802.11 and 802.16 link events before the actual handover occurs. However, there are two scenarios that the predictive FHCoP-B cannot normally complete its operations due to fast movements of the NEMO after handover. In this paper, we will propose efficient reactive FHCoP-B flows of these two scenarios to support fast and seamless handovers.