Mobile IPv6 solves the problem of node mobility though the protocol handoff process requires high cost and affects service quality. Currently, mobile IPv6 fast mobility and hierarchical mobility handoff technology enjoy wide applications, but there are still weaknesses. In view of the advantages and disadvantages of these two technologies, this paper puts forward a new fast hierarchical handoff scheme of mobile IPv6. Simulation results show that the handoff delay of fast hierarchical mobile IPv6 is shorter than that of fast mobile IPv6 and hierarchical mobile IPv6, which can reduce data packet drop-out and improve network performance.

An on-demand weighed clustering algorithm is proposed against the limitation of wireless sensor network nodes with limited energy. This algorithm obtains more local network information by means of information interaction between nodes, and by comprehensively considering such factors as the current energy value, degree and transmission power, etc. of nodes, it makes different clustering decisions as per different application backgrounds of networks. Simulation results show that this algorithm has a more rational clustering by reducing energy consumption and lengthening network lifetime, compared to Low Energy Adaptive Clustering Hierarchy, a representative clustering algorithm.

Hierarchical mobile IPv6 fastens the binding update process of micro mobile handoff and reduces handoff delay. A large number of binding updates and registrations increase signaling load and lengthen handoff delay. For this reason, it is proposed to apply tunneling mechanism to hierarchical mobile IPv6 optimization scheme (T-HMIPv6) to obtain care-of address in advance based on handoff information, conduct duplicate address detection, and complete local binding update while building a tunnel. Simulation experiments show that compared with hierarchical mobile IPv6, this scheme can greatly reduce handoff delay and packet loss rate and effectively improve mobile node's macro handoff performance.