# REISCH: Incorporating Lightweight and Reliable Algorithms into Healthcare Applications of WSNs
## Results
### Performance Analysis
#### 5.2.3 Performance Comparison  
In this section, we discuss the superiority of REISCH to existing schemes in terms of performance (Table 6 shows a comparison of the ECDSA's signature and verification (running time) between our scheme and existing schemes). Due to different environments, security parameters and network parameters such as key length, number of \(SN\)s, etc., it is difficult to compare schemes' performances. However, we made some comparisons to illustrate the superiority of REISCH on the existing schemes in terms of performance. The scheme in [17] focused on accelerating ECDSA's verification based on computation results for neighboring \(SN\)s. These computations consume additional energy. In addition, this scheme is vastly expensive if applied to a cluster scheme because \(CH\) needs to accomplish one PM  
Figure 24: Average execution time of ECDSA algorithms with different data sizes. Figure 25: Comparison of alive \(SN\)s.  
in each signature for each \(SN_{i}\) and will thus consume energy in the intermediate \(SN\)s. REISCH does not need these computations because signatures' verification is performed in \(LS\). Schemes in [18; 19; 21] used ECDSA to sign data without using homomorphic property. Consequently, the performance of the \(SN\)s would be remarkably low due to signature and verification processes in each round. The scheme in [18] addressed the bits (8 and 32) of data processing in SHA1 but did not address the cost of energy consumption by SHA1. In addition, the scheme in [19] did not support the clustering environment to reduce energy consumption and the computation time to generate and verify the signature which was not clearly indicated. Furthermore, the scheme in [22] used SHA2, which is more secure than SHA1 but performs heavy processes that significantly affect the energy of \(SN\)s. It also addresses only computations in transport while REISCH addresses computations in transport and processing using BLAKE2 bp and homomorphic property. The schemes in [20; 24; 25] rely on the use of encryption to protect data without a homomorphic property, since encryption processes extremely consume \(SN\)s resources (as mentioned in Section 3.3, Point 3), while REISCH uses signatures and homomorphic property to improve HWSN network performance. Although the scheme in [23] uses encryption and signature of data with homomorphic properties, encryption can particularly affect network performance, especially through a burden on the servers. Moreover, the scheme in [25] has implemented the RSA-2048 bits algorithm, which is significantly expensive in encryption operations. In addition, it uses several parameters such as many keys, 2048-bit key length, and \(SN_{i}\) addresses (master, replica, and gateway) that cause storage problems in the pre-deployment and registration phases (consumption of \(SN\)s resources). It uses a random routing of the sensor network without relying on a specific routing protocol such as LEACH. This scheme considers the structure of the data in the \(SN_{i}\) memory and does not pay attention to the structure of the data as they are transferred to the servers. REISCH uses XML to support performance of the \(LS\) and \(CS\) without having to convert data formats between network devices. In terms of alive \(SN\)s, REISCH provides more than 24% while the method in [78] 17.5%, the method in [79] 18.26% (100 nodes), the method in [80] 16% (100-700 nodes), and the method in [81] 7.14% (100 nodes) and 4% (50 nodes). Thus, REISCH provides longer network lifetime than the schemes in [78; 79; 80; 81]. Recent research (e.g., [26; 27; 28; 29; 30]) has used different ways to improve ECDSA's procedures. However, REISCH provides better performance in terms of ECDSA's signature and verification than existing schemes (as shown in Table 6).