This memo is a problem statement on the use of link events for enhanced handover control in network based localized mobility management. Starting from existing solutions for fast link detection the document aims at discussing possibilities to extend with a 2.5 layer the interface between MN and AR for handover control. The document also presents a set of considerations and identifies conditions where a layer 2.5 based interface offers significant advantages compared to a pure layer three solution. The document addresses separately scenarios for Localized Mobility Management and scenarios involving interactions between PMIP and CMIP.