# Energy Consumption Analysis of ISO/IEC 29192-2 Standard Lightweight Ciphers
## 6 Considerations for Enhancing ISO/IEC 29192-2 Lightweight Ciphers  
Up to this part of the study, lightweight encryption algorithms standardized according to ISO/IEC 29192-2 have been evaluated in terms of energy consumption. The results and discussions show that some algorithms in particular fail to achieve the expected energy efficiency [25]. The algorithms are secure in terms of both key sizes and number of cycles. However, it is important to reevaluate encryption algorithms used in resource-constrained systems such as IoT not only in terms of security, but also in terms of energy consumption. Academic and industrial requirements should be considered when setting security standards. This study suggests that future revisions of ISO/IEC 29192-2 could be updated to include algorithms that provide lower power consumption and better integration with embedded systems. In this section, recommendations and future research areas for the development of ISO/IEC 29192-2 lightweight encryption algorithms are discussed. Block size is a critical parameter that directly affects the processing efficiency, security level and energy consumption of an encryption algorithm. In general, larger block sizes can increase energy consumption as they require more computation while allowing more data to be processed. On the other hand, small block sizes require fewer operations but more cycles for security reasons. Although PRESENT was the algorithm with the smallest block size, it was not the most efficient in terms of energy consumption due to its 31 rounds. CLEFIA and LEA can process larger data blocks with 128-bit block size, but CLEFIA has a more complex structure, which increased energy consumption. LEA provided both a 128-bit block size and the lowest energy consumption thanks to its ARX-based operations. As a result, the impact of block size on energy consumption should be evaluated together with the number of rounds of the algorithm, its structure, and the optimization techniques used. In systems such as IoT, where low energy consumption is important, choosing the optimal block size is a critical factor for both maintaining security and ensuring energy efficiency. Lightweight block cipher algorithms should have simpler structures compared to traditional encryption methods due to their areas of use. Therefore, they involve more rounds to ensure security. While a higher number of rounds increases resilience against cryptanalysis attacks, it can negatively impact performance and energy consumption by increasing processing time. While PRESENT has the highest number of rounds, it requires relatively less processing power because it has a simple SPN structure. However, the high number of rounds increased energy consumption and decreased performance. CLEFIA aimed to provide high security with fewer rounds by using Feistel network architecture, but increased the computational cost due to the advanced diffusion layer. LEA was able to provide high security with less energy consumption with ARX-based operations. As a result, while increasing the number of rounds increases security, it increases processing time and energy consumption. In low-power applications such as IoT, determining the optimal number of rounds is a critical factor to improve energy efficiency. Therefore, the number of rounds in lightweight encryption algorithms should be optimized by balancing security and energy consumption. If the number of rounds is not carefully balanced, encryption algorithms can become vulnerable to attacks. Too few rounds may lead to weaknessesagainst differential and linear cryptanalysis, making the cipher easier to break, while too many rounds can unnecessarily increase computational overhead and energy consumption without significantly enhancing security [37]. Striking the right balance is crucial, as an insufficient number of rounds can lead to practical cryptographic weaknesses, allowing attackers to exploit structural flaws and compromise the encryption.