# An ICN-Based IPFS High-Availability Architecture
## 3 Design Overview
### Enhanced Node Performance Analysis
#### 3.2.1 Resolution Performance Analysis
Figure 5a depicts the predicted values calculated by Equations (7) and (8). From the figure, it can be seen that the resolution success rate of the enhanced node has been improved more significantly compared with the traditional IPFS node for a different number of replicas. At the same time, the introduction of the resolution node makes the enhanced node more sensitive to the replicas, and the growth of the resolution success probability is more rapid. We also studied the effect of the number of deployed augmented nodes \(m\) on \(P_{B}\) and \(P_{M}\), and the results are shown in Figure 5b. The resolution success rate of IPFS nodes using the Bitswap mechanism is independent of \(m\) and is therefore constant. At \(m=0\), no enhanced node exists in the network at this time, so the resolution success rate at this time is equal to the resolution success probability of the Bitswap mechanism. As the number of deployed nodes increases, only a small number of augmented nodes needs to be deployed to keep the performance of augmented nodes at a high level, and as the deployed nodes are enhanced, the resolution success rate tends to 1. To quantify the performance growth benefits of the enhanced nodes, we characterize them by the performance improvement ratio \(\beta\):  
\[\beta=\frac{P_{M}-P_{B}}{1-P_{B}} \tag{10}\]  
By bringing Equation (8) into the above equation, it is obtained that:  
\[\beta=P_{E} \tag{11}\]  
We take \(\beta=90\%\), that is, when the enhanced IPFS resolution performance in the Bitswap-based resolution performance improvement space is further optimized by \(90\%\) as  
Figure 5: Comparison of the resolution probability of IPFS nodes and enhanced nodes in different scenarios. (**a**) The effect of the number of replicas on the probability of resolution; (**b**) The effect of the number of enhanced node deployments on the probability of resolution. the goal, we can get \(P_{E}\) = 90%. Where \(P_{E}\) is related to the deployment of \(m\), according to the above equation, we can express \(P_{E}\) as:  
\[1-\prod_{i=n-r+1}^{n}\left(1-\frac{m}{i}\right)=90\% \tag{12}\]  
To facilitate the analysis, we define the upper and lower bounds of \(P_{M}\) by:  
\[1-\left(1-\frac{m}{n-r+1}\right)^{r}\geq 1-\prod_{i=n-r+1}^{n}\left(1-\frac{m }{i}\right)\geq 1-\left(1-\frac{m}{n}\right)^{r} \tag{13}\]  
The equality sign holds if and only if \(r\) = 1. The above equation shows that the smaller the r, the greater and closer the approximation of the upper and lower bounds to \(P_{E}\). For different retrieval data, there may be different numbers of copies within the network, but it can be seen from the above figure that both \(P_{B}\) and \(P_{M}\) show an increasing relationship with the growth of the number of copies, and when the number of replicas within the network reaches a certain level, the probability of retrieval has converged to 1. Therefore, we further constrained our goal to be to increase the probability of information retrieval from nodes while guaranteeing a small number of replicas. Therefore, we denote the number of replicas \(r\) = 0.2\(n\) according to the zipf law of network data access [40]. When \(P_{E}\) is expressed as an upper bound formula model, an upper bound value \(m_{1}\) for the number of enhanced node deployments is obtained as follows:  
\[P_{B}=1-P_{\overline{B}} \tag{6}\]0  
When \(P_{E}\) is expressed as the lower bound formula model, the lower bound value \(m_{2}\) for the number of enhanced node deployments is obtained as follows:  
\[P_{B}=1-P_{\overline{B}} \tag{6}\]1  
And the actual number of augmented nodes deployed, \(m\), can take \(m_{1}\) and \(m_{2}\) as reference, and here let \(m\) be the average of \(m_{1}\) and \(m_{2}\):  
\[P_{B}=1-P_{\overline{B}} \tag{6}\]2  
As can be seen from Figure 6, the number of enhanced nodes to be deployed is not the same for different IPFS network scales under the constraint that \(\beta=90\%\) is guaranteed, but the relationship between the two is not linearly increasing.