# EBR: Routing Protocol to Detect Blackhole Attacks in Mobile Ad Hoc Networks
## 3 Proposed Protocol
### EBR Routes Properties
Figure 2: (a) End-to-end delay vs. number of nodes (without attack); (b) End-to-end delay vs. number of nodes (with attack). behaves better than other protocols when blackhole attackers exist. The AOMDV protocol returns routes in which EBR applies its TR mechanism to select those safe paths, avoiding the single and cooperative blackhole nodes. Next, EBR selects the route with the minimum RTT out of those safe paths. Therefore, EBR can determine the safe path that has the least traffic. In the case of having blackhole nodes in the path, the amount of successful data arrived at the destination (\(l\) in Equation (1)) reduces due to packets drops for all tested protocols. This obviously increases the end-to-end time delay. This also happens with EBR but obviously with less harm than other protocols. EBR can detect most of the blackhole nodes, particularly neighboring and nodes close to the source node; however, further attackers would be hard to avoid. In Figure 3, the network has 100 nodes during the whole simulation time. In Figure 3a, there are missing data packets because of the network's nature of being wireless, where data can be dropped and damaged because of the congestion, collision, etc., over time. However, as EBR selects routes based on the minimum RTT, its behavior is better than other protocols. In Figure 3b, EBR applies both its TR mechanism and minimum RTT to select the safest route with the least congestion. EBR obviously performs better than other protocols, as blackhole attackers can be detected and, accordingly, data packets follow paths avoiding suspicious nodes. On the other hand, SUPERMAN performs better than AODV and AOMDV, as it uses encryption and network layer security to prevent malicious nodes; however, it is incapable of detecting blackhole attacks as efficiently as EBR does. SUPERMAN uses very complicated cryptographic and key-exchange mechanisms to maintain the data's safety, and this consumes a significant amount of energy, particularly in Figure 4b compared to Figure 4a. On the other hand, EBR uses less overhead in the TR mechanism to identify and resist blackhole attacks. Additionally, EBR uses the concept of minimum RTT to select the shortest route among those safe paths. This in turn would reduce the energy consumption and save the power of the nodes. This implies the smallest number of nodes and also the least congested routes. Figure 3: (a) End-to-end delay vs. simulation time (without attack); (b) End-to-end delay vs. simulation time (with attack). In Figure 5a,b, we observe that at the range where number of nodes is greater than 80, PDR becomes almost constant and packets dropping are minimal. At this range, nodes are close to each other, and, therefore, the random loss of packets will be minimal. Consequently, the delivery ratio will be stable according to Equation (3). When the number of nodes is 100, EBR can achieve the highest PDR at 52% and 58%, with and without attack, respectively, whereas PDR for SUPERMAN is somewhat close to 40% and 50%, with and without attack, respectively. EBR uses its TR mechanism to detect the blackhole nodes and selects the legitimate path with the minimum RTT. This reduces the packets drops and maximizes the PDR sufficiently compared to other protocols. In Figure 6a, EBR performs better than other protocols because the path selection is based on the minimum RTT rather than least number of nodes used by other protocols. This implies less congested routes, which in turn reduce the possibility of packets drops and, therefore, enhances the throughput. In Figure 6b, EBR gets a higher throughput gain of 7%, 60%, and 180% compared to SUPERMAN, AOMDV, and AODV, respectively. This

Figure 4: (a) Energy vs. number of nodes (without attack); (b) Energy vs. number of nodes (with attack). Figure 5: (a) PDR vs. number of nodes (without attack); (b) PDR vs. number of nodes (with attack). shows the efficiency of the EBR protocol, where it can achieve higher data delivery even with an increasing number of nodes in a MANET.