Optimization of Handover Performance by Link Layer Triggers in IP-Based Networks: Parameters, Protocol Extensions and APIs for Implementation

The detection and triggering of handover is an important functionality of handover that has a strong impact on the performance in terms of handover latency and packet loss, in particular in scenarios with frequent handover. It is common to all IP-based mobility solutions that they provide network layer trigger for handover – for example, based on the lifetime field or the network prefix in Mobile IP advertisements. The technical report covers the following aspects of link layer trigger for handover. First, parameters and their combinations for link-layer triggers are identified. Second, the potential performance gain of link layer triggers in comparison of network layer triggers are quantified for Mobile IP and Hierarchical Mobile IP by means of a simulative study. Third, the interaction of the link layer and the network layer are described for Mobile IPv6 and its hierarchical variant as well as for the fast handover extensions of Mobile IPv6. Fourth, the requirements for an applicationprogramming interface (API) are summarized and existing APIs for interaction between link-layer and network layer are evaluated.