# EBR: Routing Protocol to Detect Blackhole Attacks in Mobile Ad Hoc Networks
## 2 Related Work  
AODV is a commonly used reactive protocol. However, it is at risk to the blackhole node as being a critical security threat to routing protocols, as pointed out in [20]. [PERSON] et al. [21] concluded that AODV has a low performance when the selected route has blackhole nodes. Also, in [22; 23], it was proved experimentally that the performance of the AODV protocol collapsed in the presence of a blackhole attack. [PERSON] et al. [24] amended the AODV mechanism to lessen the possibility of having a wicked or single-blackhole node. However, this mechanism is susceptible to cooperativeblackhole threats when two sy attackers are cooperating to cause the attack. Also, this protocol ignores the shortest path whenever there are no malicious nodes. SAODV [25] is an improved AODV routing mechanism to protect AODV against attacks. In this protocol, AODV requires a supplement message, which is a fusion of digital signature with the use of the private key of the actual sender and a hash value of the hop count. This message adds an extra routing overhead cost, and this accordingly augments the energy consumption of nodes. In [26], a blackhole detection method called the Cooperative Bait Detection Scheme (CBDS) was proposed. It mainly aimed to prevent blackhole nodes from beginning collaborative blackhole attacks in MANETs. Using a backward tracking method, malicious attackers are detected and prevented from taking part in the data routing. In this model, when there is an obvious degradation in the packet delivery ratio (PDR), an alarm is triggered to start the malicious node detection scheme again. PDR may degrade for any other reason, such as traffic problems; however, this algorithm will consider it as a result of the existence of malicious nodes. The authors in [27] proposed a Security Using Pre-Existing Routing for Mobile Ad hoc Networks (SUPERMAN) protocol. This mechanism solves problems of node certification, medium access control, and secure transmission for MANETs. SUPERMAN combines routing with security. However, it has a lot of overhead in comparison with other protocols, particularly when the number of nodes increases. To overcome the negative effect caused by the blackhole nodes, [28] developed an evolutionary self-cooperative trust (ESCT) mechanism that fulfills high throughput and PDR; however, ESCT increases the routing overhead cost and also extends the end-to-end delay. In [29], the authors proposed a protocol that utilizes feedback such as ACK messages from the destination or the intermediate nodes back to the source node. This is to monitor the status of the neighboring nodes as being malicious or legitimate. This approach is complicated and even improves the performance insufficiently. The authors of [30] used a new Receive Reply method that enables the source node to scrutinize the destination sequence number linked with the RREP packet. This method introduced a pre-RREP message to determine the good nodes and malicious ones. This is a general approach to detect any intrusion. This system likely collapses in the presence of multiple collaborative blackhole nodes. In [31], the authors provided an enhanced version of the AODV protocol to mitigate the blackhole attack. Using VERIFY and CHECKVRF messages, the proposed approach stretches the standard AODV protocol for certification purpose. When the destination receives the CHECKVRF packet, it replies with the FINALREPLY message to guarantee the genuineness of the path. The main concerns of this method are obviously the extra routing overhead appended in addition to the excessive energy consumption. In [32], the authors proposed a mechanism based on setting a security bit in the RREP message. This model assumes that the suspicious node has no anxiety about that validity. The source utilizes that path and sends its data packets if the security bit is still one. In any other case, it assumes that the path passes through a sy node and accordingly drops that RREP packet.