Improving Handover Performance by Switching Between Unicast and Anycast Addressing

With increased popularity and pervasiveness, mobile networking has become a definite trend for future networks. Users strongly demand that the connectivity of ongoing services be retained while roaming across different points of attachment. Efficient handover schemes are essential to the aforementioned vision. However, there are time-consuming procedures in the process. Various research has been devoted to the acceleration of movement detection and registration. However, a time-consuming operation, i.e., duplicate-address detection (DAD), was overlooked by most studies. One novel scheme that features anycast technique is developed and presented in this paper. The proposed approach switches to anycast addressing during handover and switches back to normal unicast addressing after all required operations are completed. By switching to anycast addressing, a mobile node can continue the reception of packets from its corresponding node before its new care-of address is actually validated. Thus, transmission disruption can effectively be minimized. In addition, a simple but effective buffer-control scheme is designed to reduce possible packet loss and prevent the out-of-order problem. Analytical study reveals that improved performance can be guaranteed, as reflected in the simulation results.