# A Survey on Energy Drainage Attacks and Countermeasures in Wireless Sensor Networks
## 4 Recent Review Based on State-of-the-Art Works for Energy Drain Attack
### Data Link Layer  
[PERSON] et al. [37] published a comprehensive survey concerning security issues in the data link layer. They explained security issues and described diverse attacks, such as energy exhaustion, as the specific attack for the data link layer. Abnormal energy depletion attacks in the data link layer can be accomplished by accepting and processing bogus messages as well as prohibiting the sensor node from turning to sleep mode. The second case is the denial-of-sleep attack, which is a specific type of DoS attack. Several countermeasures \begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Reference** & **Key Features** & **Advantage** & **Disadvantage** \\ \hline
[26] & Physical-layer authentication & High applicability & High complexity \\ \hline
[27] & Game theoretic mobility scheme & Low energy consumption and less network overhead & Flow-table updates \\ \hline
[28] & Pinpointed anti-jammer localizer & Low energy consumption & Comparison with relative old standards \\ \hline
[29] & Evolutionary Fibonacci Branch Search & High reachability and fast convergence & High complexity \\ \hline
[33] & Multi-agent Q-learning & prompt decision for anti-jamming strategy & Space complexity for Q-table and joint Q-table \\ \hline
[34] & Neural network & High adaptability & Multiple antennas \\ \hline
[35] & Deep reinforcement learning & Quick adaptability for new environments & High complexity \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Comparison of anti-jamming methods. have been devised to address these attacks in the data link layer. Continuous bogus traffic forces the node awake. Thus, these two attacks are closely related to energy drain in WSNs. [PERSON] and [PERSON] [38] reviewed papers related to security protocols at the data link layer for WSNs and highlighted the security research issues and limitations of existing schemes. Using two papers, we found that most of the research work for energy drain attacks is focused on the DoS and denial of sleep at the data link layer. First, a bogus message for DoS can be prevented by the encryption scheme. However, because of a computing constraint on a node, lightweight encryption is desirable. To address this problem, [PERSON] et al. [39] proposed a novel scheme named FlexCrypt, which was an automated lightweight cryptographic method. Lightweight features were accomplished by selecting encryption parameters based on the available resources on a node with a novel lightweight dynamic key management and authentication method. Through the simulation results, the authors demonstrated that the proposed scheme, FlexCrypt, can save energy by more than 66%. [PERSON] et al. [40] analyzed the trade-off between received packets and energy consumption by comparing two well-known MAC protocols, Berkeley MAC (BMAC) and lightweight MAC (LMAC). For comparison, various cryptographic techniques such as AES, RSA, and ECC were applied for the energy drain attack and the impersonation attack. Thus, the relationship between encryption and energy drain was identified. [PERSON] and [PERSON] [41] presented a novel lightweight authentication medium access control (MAC) protocol for CR-WSNs to discard unauthenticated packets. The proposed scheme was used by adopting hash algorithms (SHA-1) and XOR operations. The proposed scheme can lower computational costs. Second, most existing energy drain attacks target the data link layer. The most well-known attack is called denial of sleep, a specific case of DoS attacks in WSNs. This attack prevents the node from going into the sleep phase. This attack rapidly drains its energy supply. During actual measurement, a sensor node lasts for months with general energy consumption, whereas the denial-of-sleep attack reduces the lifetime in a few days by keeping the radio transmitter system on. Therefore, we reviewed the mitigation of the energy drain attack to make the whole network work as normal. Table 6 shows a comparison of existing methods in terms of their advantages and disadvantages.