Recently, there have been a lot of research and investigation to improve handover latency of mobile IPv6 (MIPv6). The handover latency is one of the most important factors because performance of TCP flows as well as realtime traffic degrades sharply as the latency increases. The MIPv6 handover process consists of movement detection, duplicate address detection (DAD), and binding update. Among the three components, DAD has been identified as the most critical factor. In this paper, we introduce novel schemes to reduce the DAD delay. By utilizing tentative address that an access router provides, a mobile node pre-determines its care-of-address before L2 handover such that the DAD period can be greatly reduced. We also devise a mechanism that reduces the messaging overhead via link layer assistances. Extensive performance analyses show that the proposed scheme significantly enhances the performance of MIPv6.