Multihop Wireless Networks: Opportunistic Routing

9.2 Attacks on Opportunistic Coordination Protocols

In addition to bluffing on the link quality to degrade the performance of opportunistic routing, an attacker can attack the candidate coordination protocols. We can basically classify the opportunistic routing MAC coordination protocols discussed in Chapter 6 into two categories: implicitly prioritized and explicitly prioritized. The implicitly prioritized ones include GeRaF MAC and the contention-based forwarding, where the transmitter does not include a candidate list in the header of the data packets, and the forwarding candidates contend for the right of the packet relay. On the opposite side, the explicitly prioritized ones include ExOR batch-based forwarding, slotted ACK, compressed slotted ACK, and fast slotted ACK (FSA), where the transmitter explicitly includes the candidate list information in the data packet header and the forwarding candidates follow an order to forward the packets. In the following discussion we assume the goal of the attacker is to claim the relay responsibility for as many as packets it can whether it correctly received the packets or not. After the attacker obtains the relay responsibility of the packets, if it indeed received the packets, it can either drop them (black hole attack), selectively relay them, or forward them normally (but this may lead to suboptimal routing). If it does not correctly receive the packets, those packets are implicitly dropped.

9.2.1 Attack on Implicit-Prioritized Coordination ...