# SC-SA: Byte-Oriented Lightweight Stream Ciphers Based on S-Box Substitution
## 4 Performance
This is because, during their design, more consideration was given to hardware, neglecting the complexity of the implementation logic when implemented in software. The variant RC4 algorithm [28], in order to enhance the obfuscation capability of the key scheduling algorithm, embeds a loop, resulting in decreased performance. Figure 9: The comparison of memory usage. Figure 11: The comparison of time consumption on \(\times\)86 partially. Figure 12: The comparison of time consumption on ARM. Figure 10: The comparison of time consumption on \(\times\)86. Figure 13: The comparison of time consumption on ARM partially. Based on the comparison between different platforms, there is a demonstrated platform diversity between the variant RC4 and Snow3G. Snow3G has an advantage on the \(\times\)86 platform, while the variant RC4 has an advantage on the ARM platform. Tables 5 and 6 show the time required by different encryption algorithms to encrypt files of various sizes on the ARM and X86 platforms, respectively. The ratio of memory usage relative to algorithm implementation for SC-SA, RC4, Snow3G, and ZUC when outputting key streams of the same size is shown in Figure 14. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Size** & **SC-SA** & **RC4**[22] & **ZUC**[27] & **RC4 +**[24] & **Snow3G**[26] & **Variant-RC4**[28] \\ (**Byte**) & **(ms)** & **(ms)** & **(ms)** & **(ms)** & **(ms)** & **(ms)** \\ \hline
1 K & 0 & 0 & 1 & 0 & 0 & 0 \\
100 K & 0 & 0 & 3 & 0 & 62 & 47 \\
200 K & 0 & 0 & 8 & 0 & 125 & 109 \\
400 K & 0 & 0 & 15 & 0 & 219 & 203 \\
800 K & 2 & 2 & 16 & 7 & 435 & 407 \\
1600 K & 7 & 7 & 31 & 10 & 938 & 828 \\
3200 K & 15 & 15 & 47 & 16 & 1969 & 1640 \\
6.25 M & 31 & 31 & 94 & 47 & 3750 & 3266 \\
12.5 M & 78 & 47 & 188 & 94 & 7813 & 6484 \\
25 M & 172 & 109 & 375 & 156 & 14,844 & 12,985 \\
50 M & 344 & 203 & 703 & 329 & 31,157 & 26,172 \\
100 M & 688 & 437 & 1531 & 657 & 63,907 & 52,906 \\
200 M & 1390 & 828 & 3037 & 1296 & 122,376 & 106,500 \\
400 M & 2750 & 1641 & 6032 & 2609 & 240,752 & 216,297 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: X86 performance results. Figure 14: The comparison of efficiency. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Size** & **SC-SA** & **RC4**[22] & **RC4 +**[24] & **ZUC**[27] & **Variant-RC4**[28] & **Snow3G**[26] \\ (**Byte**) & **(ms)** & **(ms)** & **(ms)** & **(ms)** & **(ms)** & **(ms)** \\ \hline
1 K & 0 & 0 & 0 & 0 & 12 & 10 \\
100 K & 27 & 10 & 32 & 38 & 908 & 867 \\
200 K & 55 & 20 & 66 & 73 & 1812 & 1720 \\
400 K & 102 & 41 & 98 & 135 & 3618 & 3427 \\
800 K & 191 & 79 & 188 & 257 & 7233 & 6866 \\
1600 K & 369 & 145 & 333 & 501 & 14,462 & 13,674 \\
3200 K & 726 & 279 & 699 & 989 & 28,920 & 27,395 \\
6.25 M & 1439 & 546 & 1388 & 1966 & 57,838 & 54,751 \\
12.5 M & 2865 & 1078 & 2780 & 3917 & 115,674 & 109,308 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: ARM performance results. Through comparison, it can be observed that the cryptographic algorithm proposed in this paper demonstrates significant advantages in terms of performance and resource utilization compared to non-lightweight stream cipher algorithms and cryptographic algorithms not designed for software-oriented implementations. Additionally, it also exhibits clear advantages when compared to lightweight cryptographic algorithms designed for both software and hardware implementations, such as RC4.