# Mathematical Models for Named Data Networking Producer Mobility Techniques: A Review
## 3 Recent Mobility Techniques
### Anchor Technique  
In the context of anchor in NDN, the topology situation refers to the organization and interconnection of nodes, explicitly emphasizing the positions of anchor points. Anchor points function as pivotal hubs that streamline the process of retrieving content by overseeing the exchange of information between creators and users. Hence, analyzing the strategic placement of anchor points in the network is essential. The overall efficiency of information distribution can be influenced by various strategies for picking anchor points, such as hierarchical or distributed approaches. Other than that, comprehending the impact of network topology on the choice and effectiveness of anchor points aids in optimizing the anchor model. The forwarding technique in anchor specifies how content is transmitted from producers to consumers via the anchor points. The process entails the methods by which data packets navigate the network, utilizing anchor points to route and deliver content  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Metric** & **Description** \\ \hline \(\mathcal{Q}_{\text{data}}\) & Data packet size (bytes) \\ \(\mathcal{Q}_{\text{Int}}\) & Interest packet size in (bytes) \\ \(\alpha\) & Latency rate between producer and consumer (bytes) \\ \(\varsigma\) & Latency rate between producer and new location producer’ (bytes) \\ \(\text{P}_{\text{T}}\) & Movement time for producer (ms) \\ \(l_{\text{rend}}\) & Packet arrival time at server rendezvous (ms) \\ \(l_{\text{int}}\) & Packet Interest time transmission (ms) \\ \(\text{\text{\texteffectively. It is essential to assess the efficacy of various forwarding techniques, such as direct forwarding, anchor-based forwarding, or hybrid approaches. Gaining insight into how these techniques manage data dissemination, improve response time, and adjust to fluctuations in network conditions improves comprehension of an anchor in NDN. The mobility characteristics of handover in anchor pertain to the model's ability to handle the migration of producers or consumers within the network. This encompasses factors such as the velocity of producer movement, the frequency of transitions, and the methods for ensuring uninterrupted content delivery during mobility events. It is essential to analyze how the anchor adjusts to dynamic changes in the locations of producers and consumers. This entails assessing the time it takes to transfer control from one system to another, the capability to choose suitable reference points during movement instances, and the influence of movement parameters on the effectiveness of retrieving content. The signaling cost in anchor refers to the additional expenses from transmitting control messages to manage anchor points, facilitate handovers, and coordinate between producers and consumers. Assessing the efficiency of anchors in NDN requires a crucial evaluation of the signaling cost. Optimizing the model's performance requires minimizing the signaling overhead while guaranteeing good anchor point selection and handover management. Examining the influence of signaling on network resources, latency, and scalability yields valuable information on the overall effectiveness of the anchor method. When examining the anchor model in NDN, it is crucial to recognize particular constraints and establish specific assumptions to define the scope of its applicability. The system's limitations include static anchor points, dependency on anchor points, handling dynamic network conditions, scalability concerns, and security and privacy implications. On the other hand, the system assumes stable anchor points, predictable producer and consumer behavior, adequate network connectivity, centralized coordination, and a homogeneous network environment. Figure 6 illustrates that a fixed point from the producer serves as the anchor node to monitor the producer's movement. Compared to a DNS-based approach, the anchor transmits interest directly to the producer, resulting in cost, energy, and time savings.