## 3 Cluster-Disjoint Multipath Routing Protocol
### Grid Cluster Construction
However, packet transmission often fails due to interference and collision between paths, resulting in low end-to-end

Figure 6: Energy Consumption by End-to-End distance. Figure 7: End-to-end Transmission Success Ratio by Single-hop Transmission Success Ratio. transmission success ratio and low energy consumption. In the case of RMR, similar to the proposed scheme, multipaths are constructed as the single-hop transmission success ratio decreases. However, as mentioned earlier, it could not construct a sufficient number of paths and consumed less energy than the proposed scheme. In the case of the proposed scheme, as the single-hop transmission success ratio decreases, it can construct a larger number of paths than RMR and achieve the required end-to-end transmission success ratio. However, if the single-hop transmission success ratio is extremely degraded, it is difficult to construct a sufficient number of paths and impossible to achieve the required end-to-end transmission success ratio. Due to this phenomenon, energy consumption is reduced when the single-hop transmission success ratio is low. ### Simulation Results under Path Failure

In this section, we present the performance evaluation results when some nodes in the paths are broken while each protocol is transmitting packets. Path failure affects various performance metrics; in particular, it has a significant negative impact on the end-to-end transmission success ratio. Figure 9 shows the end-to-end transmission success ratio when path failure occurs during packet transmission for each protocol. For this purpose, we assume a situation where each protocol constructed a multipath and is ready to transmit a packet. To evaluate the end-to-end transmission success ratio, we calculate the number of packets that arrive at the sink when some nodes in the path are broken during the transmission of 200 packets from the source node. In the case of FD-AOMDV, when path failure occurs, it exploits RREQ and RREP messages to discover the path as in path construction. This results in a lower transmission success ratio until a new path is constructed. In the case of the other two schemes, only the region (or grid cluster) where the packet should be transmitted is specified, and the nodes selected in each transmission process are selected differently according to the criteria of each protocol at each packet transmission. In other words, even if an arbitrary node is damaged, it is immediately replaced by another node in the transmission process and the packet is transmitted. Therefore, both schemes satisfy the required end-to-end transmission success ratio even if path failure occurs. Figure 8: Energy Consumption by Single-hop Transmission Success Ratio. ## 5 Conclusions

In Wireless Sensor Networks (WSNs) exploited to collect information from interest regions, the end-to-end transmission success ratio is one of the most important factors in achieving their main purpose. To improve the end-to-end transmission success ratio, multipath routing protocols, which exploit two or more transmission paths to deliver data, are typically exploited. However, existing schemes suffer from collisions and interference in the transmission process, or time delay and energy wastage due to pre-path configuration and path recovery. Therefore, we propose a cluster-disjoint multipath routing protocol to overcome the above limitations. In the proposed scheme, the network is divided into network clusters of a certain size during the network initialization phase. During packet transmission, each path is determined and transmitted on a cluster-by-cluster basis. Therefore, no path construction time is required for data transmission. In addition, even if some sensors are damaged during the transmission process, data could be delivered immediately via other sensors in the cluster. Therefore, in order to recover the damaged path, time is not require.