# Mathematical Models for Named Data Networking Producer Mobility Techniques: A Review
## 3 Recent Mobility Techniques  
Currently, there are only a limited number of NDN mobility strategies available. However, most interest in producer mobility pertains to rendezvous, anchor, and anchorless operations. Therefore, it is imperative to emphasize these three methodologies and their potential for future study adaptation. This section provides a complete description of the topology situation, forwarding method, mobility parameters of handover, and signaling cost. Handover in the context of mobility refers to the seamless transfer of mobile transmission from an old base station to a new one, ensuring minimal disruption. It is essential, as it facilitates the establishment of data sessions between mobile devices. Moreover, handover latency and failure are prominent concerns in mobility, as they impede and interrupt service. On the other hand, the signaling cost parameter refers to the level of traffic demand that occurs when transmitting content and sending signaling messages. Consequently, ref. [72] stated that the handover rate refers to the likelihood that a consumer will transition to the next place during a single mobility time. Handover data latency is the period that elapses between the start of a handover procedure, such as when a producer changes location, and the successful transmission of material to the consumer. It encompasses the duration required for interest packets to reach the new producer, the duration for the new producer to handle the request, and the duration for the data to travel over the network. The measurement commences at the onset of the handover procedure, usually when the consumer perceives the necessity for a handover. Correspondingly, the measurement is complete once the consumer receives the new producer's specified content. It is essential to record time stamps at different stages of the handover process to conduct a detailed analysis. The assessment of latency's impact should consider the fluctuating network conditions across different scenarios. On the other hand, signaling cost refers to the additional expenses incurred due to the transmission of messages during handovers or other network events. In the context of NDN, this may encompass interest, data, or control packets explicitly associated with signaling. It examines the quantity and dimensions of signaling packets interchanged between entitiesthroughout the handover procedure. Subsequently, it quantifies the number of signaling packets (such as interests and control messages) transmitted throughout the handover process. It also assesses the magnitude of each signaling packet to ascertain the overall amount of data linked to signaling. Total packet loss measures the percentage or exact count of packets that fail to reach their intended destination during the handover procedure. It includes both interest and data packets that could be lost due to network circumstances or inefficiencies in the handover mechanism. Other than that, it determines the proportion of lost packets concerning the overall number of packets transmitted during the handover. Note that researchers use several simulators of mobility solutions for NDN experiments. The most popular simulator that supports NDN architecture and library is ndnSIM, which is a network simulator framework specifically developed to support study and experimentation in the NDN field. NDN is a developing network architecture that changes communication from the conventional host-centric method employed in the current Internet to a data-centric approach. Moreover, ndnSIM is constructed upon the NS-3 (Network Simulator version 3) foundation, enhancing its capabilities to simulate NDN-based communication scenarios. Comparisons of current simulation frameworks for NDN, their constraints, and particular requirements for data access were developed. Notably, ndnSIM is an open-source simulator for NDN that seamlessly integrates with the commonly utilized ns-3 network simulator. The software offers a comprehensive implementation of the NDN protocol stack.