There are two critical issues involved as a mobile node moving across two different network sub-domains. One of them is to minimize the possible packet loss and the other is to shorten the handover time. Fast handover is a remedy to these problems. It minimizes the packet loss by making use of buffers, and speed up the handover procedure by L2 triggering. There are two components contributing to the handover delay, namely L2 handover delay and L3 handover delay. The L3 handover delay consists of movement detection delay, duplicate address detection delay, as well as registration delay. With fast handover, the movement detection delay can be lowered by using L2 trigger, and the registration delay can be decreased by buffering and tunneling. However, the problem of out-of-order packets is still in its existence. A novel handover scheme incorporating the anycast technology is developed and presented in this thesis. With refined buffer control scheme and the switching between unicast and anycast addressing, the handover performance can be greatly improved by the proposed approach.

This master's thesis analyses and demonstrates selected IPv6 attacks including two Man-in-the-Middle attacks and one Denial of Service attack - Rogue Router Advertisement, Neighbor Cache Poisoning and Duplicate Address Detection DoS, respectively. In the first part the author presents necessary information related to the issue and provides detailed information on how to realize these attacks in practice using publicly available tools. The second part of the thesis presents various ways of mitigating presented attacks, analyses implementations of some of those countermeasures on Cisco and H3C devices and discussess their applicability.