# DNA-PRESENT: An Improved Security and Low-Latency, Lightweight Cryptographic Solution for IoT
## 4 Security, Cost, and Performance Analysis
### Performance Analysis  
A performance analysis of DNA-PRESENT against other lightweight block ciphers is performed and summarized in this section. This study specifically focuses on block ciphers, with both the benchmarks and proposed algorithm belonging to this category. While there are many other prominent techniques, such as stream ciphers, a direct comparison with these would not have been entirely appropriate and may have introduced confusion due to the fundamental differences. Therefore, the selected algorithms range from LED, RECTANGLE, PRESENT, DNA-PRESENT, PUFFIN, mCrypton, I-PRESENT, NOEKEON, PRINCE, and ICEBERG to AES. These algorithms have three things in common: SPN structure, 128-bit key size, and applicability to resource-constrained devices. These algorithms are compared against DNA-PRESENT and summarized in Table 11. These algorithms are compared for block size, key size, and number of rounds, followed by the cost comparison as GE. The hardware performance in the form of latency, throughput, hardware efficiency, and figure of merit are also used as evaluation parameters and are explained as follows:  
1. **Latency**: In IoT, resource-constrained devices need to be responsive around the clock and do not require a time lag; hence, latency becomes an important evaluation criterion \begin{table}
\begin{tabular}{l l l l l} \hline \hline  & **DNA-PRESENT** & & & **PRESENT** \\ \hline
**Module** & **GE** & **\%age** & **GE** & **\%age** \\ \hline Data Sate & 384.39 & 15.26\% & 384.39 & 20.38\% \\ S-Layer & 448.45 & 17.80\% & 448.45 & 23.77\% \\ Left-shift & 0 & 0 & N\(/\)A & N\(/\)A \\ DNA Replication & 16 & 0.64\% & N\(/\)A & N\(/\)A \\ Right Shift & 0 & 0 & N\(/\)A & N\(/\)A \\ P-Layer & 0 & 0 & 0 & 0 \\ Counter.State & 28.36 & 1.13 & 28.36 & 1.50\% \\ Counter.Combinatorial & 12.35 & 0.49 & 12.35 & 0.65\% \\ KSA & 1625.65 & 64.53\% & 1009.03 & 53.50\% \\ Other & 3.67 & 0.15 & 3.67 & 0.19\% \\ \hline Total & 2518.85 & 100\% & 1886.25 & 100\% \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Cost requirements for DNA-PRESENT and PRESENT. for block ciphers. The time involved in encrypting a single block of plaintext during the encryption process is termed latency, [12; 33; 77; 78], mathematically expressed as Equation (6). \[L=k\times t_{cycles}\] (6) \[L\] is the latency, the variable \[k\] denotes the number of clock cycles required for computing a single block of plaintext and its corresponding ciphertext, and \[t_{cycles}\] is the time required for one cycle. ICEBERG has the lowest latency with 16 Cycles/block, followed by DNA-PRESENT with 17 Cycles/block. 2. **Throughput (TP)**: The number of bits produced per second at a designated frequency in the encryption-decryption process is referred to as throughput [33]. This throughput is always calculated at a specified frequency, and it is 100 kHz for hardware implementation. Mathematically, throughput can be expressed as Equation (7): \[Throughput=\frac{Block\ Size\times Frequency}{Number\ of\ cycles\ per\ block}\] (7) The throughput is measured in Kb/s, and ICEBERG achieved the highest value with 400 Kb/s followed by DNA-PRESENT with 376.47 Kb/s. 3. **Hardware Efficiency (HE)**: Hardware efficiency is a critical parameter for evaluating algorithms as it represents the ratio of performance to the incurred cost [33]. The performance is the value obtained from the throughput, whereas the cost is the GE for hardware implementation. The highest HE is observed for PRINCE with 152.77 Kbps/KGE, followed by DNA-PRESENT with 149.45 Kbps/KGE. 4. **Figure of Merit (FoM)**: The performance of a block cipher is subjected to an ultimate evaluation matrix, i.e., figure of merit (FoM) presented by [79]. It was introduced to overcome the weaknesses in the existing hardware evaluation matrices by finding the optimal cost performance evaluation. Mathematically, it can be expressed as Equation (8): \[FoM=\frac{T}{A^{2}}\] (8) where \[T\] is the throughput and \[A\] is the area of implementation measured as GE.