text: In this paper, we propose RECOUP, a reliable group communication routing protocol for IoT networks. RECOUP efficiently uses a low-overhead cluster-based multicast routing technique on top of the RPL protocol. RECOUP increases the probability of message delivery to the intended destination(s), irrespective of the network size and faults (such as broken links or non-responsive nodes), and in the presence of misbehaving nodes.We show that the cluster-based routing mechanism of RECOUP remains robust in presence of various topology (i.e., rank and sybil) and data communication (i.e., blackhole, wormhole, and jamming) attacks targeting the IoT networking infrastructure.An implementation of RECOUP is realized in Contiki. Our results show the effectiveness of RECOUP over state-of-art protocols concerning packet delivery ratio to 25 , end-to-end delay down to 100 ms, low radio transmissions required for per packet delivery to 6 mJ, and most importantly, it improves the robustness and scalability of data communication process in thewhole network.
  @cite_5: Smart metering application has received a lot of attention from the research community lately. Usually, LLN based network runs on RPL protocol which constructs a DAG structure for its normal operation. In this paper, we devise a wormhole attack scenario in such a network. Furthermore, we propose a Merkle tree based authentication protocol which runs on the notion of constructing a tree of hashed security information. We evaluated the approach by formulating the wormhole problem as graph theoretic problem and have shown the effectiveness of the proposed Merkle tree based approach for authenticating communications. Furthermore, we perform simulations in NS 2 to observe the network performance by adopting Merkle tree based to prevent from disrupting the links and observed boost in throughput, reduction in jitter and end to end delay. In the end, we have taken the step towards optimizing the performance of the algorithm by proposing an effective tree traversal algorithm which works on the notion of electing nodes as root in a large scale network from where a Merkle tree will be originated this will assist in managing the authentication in a huge sized network broken down into many trees avoiding wormhole attacks in the network.
  @cite_1: In this work, we present the results of a study on the detrimental effects of sinkhole attacks on Wireless Sensor Networks (WSNs) which employ the Routing Protocol for LLNs (Low-power and Lossy Networks). A sinkhole is a compromised node which attempts to capture traffic with the intent to drop messages, thus degrading the end-to-end delivery performance, that is, reducing the number of messages successfully delivered to their destination. The mechanism by which the sinkhole captures traffic is by advertising an attractive route to its neighbors. We evaluate two countermeasures addressing the sinkhole problem: a parent fail-over and a rank authentication technique. We show via simulation that while each technique, applied alone, does not work all that well, the combination of the two techniques significantly improves the performance of a network under attack. We also demonstrate that, with the defenses described, increasing the density of the network can combat a penetration of sinkholes nodes, without needing to identify the sinkholes.
summary: As RPL or an extension of RPL are the most used routing protocols in IoT networks. We now briefly discuss the security challenges that these protocols might face during the routing process. Authors in @cite_1 propose a sinkhole attack mitigation method that integrates rank authentication with parent fail-over. The proposal uses DIO message along with the one way hash function technique for rank authentication. The root node generates hash value by selecting random numbers, and broadcast these values through DIO messages. When the root node again broadcast the initially selected random number securely then intermediate nodes can verify its parent rank using the intermediate hops number. @cite_5 authors propose a Merkle tree authentication based solution which can be used to prevent wormhole attack on RPL protocol. In this proposal, the RPL tree is formed in the reverse direction by using the node ID and public key which are used to calculate the hash values. After the Merkle tree formation, the authentication for any node starts from the root node and if any intermediate node fails to authenticate, a possible wormhole is detected.