Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Contents lists available at ScienceDirect Journal of King Saud University – Computer and Information Sciences journal homepage: www.sciencedirect.com A multi-objective privacy preservation model for cloud security using hybrid Jaya-based shark smell optimization Danish Ahamad a,⇑, Shabi Alam Hameed b, Mobin Akhtar c a Department of Computer Science, College of Science & Arts, Sajir, Shaqra University, Saudi Arabia Department of Computer Science, Collage of Science & Humanities, Huraymla, Shaqra University, Saudi Arabia c Department of Basic Sciences, Riyadh Elm University, Saudi Arabia b a r t i c l e i n f o Article history: Received 8 August 2020 Revised 17 October 2020 Accepted 17 October 2020 Available online 22 October 2020 Keywords: Cloud security Privacy preservation Optimal key generation Jaya-based shark smell optimization Hybrid optimization Multi-objective function a b s t r a c t The rising volume of sensitive and personal data being harvested by data controllers has increased the security essentials in the cloud system. The cloud module is not used just to store the data, but also to process them on cloud premises. Security for the cloud premises is essential as the cloud has lot of outsourced, unprotected sensitive data for the public access. This has resulted repeated data violations, and thus there is a need for the advanced legal data protection constraints. Various studies were conducted to adopt the privacy preservation in the cloud, and most of the state-of-the-art techniques fail to handle the optimal privacy when dealing with sensitive data, as it requires separate data sanitization and restoration models. To overcome this challenge, this paper tempts to develop the privacy preservation model in the cloud environment using the advancements of artificial intelligent techniques. Artificial Intelligent capabilities are working in the business cloud computing environment to make organizations more efficient, strategic, and insight-driven. However, by hosting the data, cloud computing offers businesses high flexibility, agility, and cost savings. The two main phases of the proposed privacy preservation system are the data sanitization and restoration. Moreover, the proposed sanitization process depends on the optimal key generation, which is performed by the hybrid meta-heuristic algorithm. This hybrid algorithm merges two well-performed algorithms, such as Shark Smell Optimization (SSO) and Jaya Algorithm (JA), and thus termed as Jaya-based Shark Smell Optimization (J-SSO). The optimal key generation is accomplished by deriving a multi-objective function that involves the parameters, such as the degree of modification, hiding ratio, and information preservation ratio. Finally, the performance analysis has proved the efficiency of the proposed model over the state-of-the-art models in enhancing cloud security. Ó 2022 Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 1. Introduction The Cloud computing sector offers a massive amount of support to the global environment in diverse areas like education, medical, and business (Alabdulatif et al., 2017). Security is a major part of the services that are offered around the globe. Data security plays an important role in a cloud network environment. Numerous types of security risks like security applications, key management and encryption, access and identity management, audit scheduling, ⇑ Corresponding author. E-mail address: danish.ahamad@gmail.com (D. Ahamad). Peer review under responsibility of King Saud University. Production and hosting by Elsevier and physical and user access control (Tysowski and Anwarul Hasan, 2013; Chun-TaLi and Chun-ChengWang, 2018) are listed in the cloud data. In recent days, the encryption of data is carried out using several encryption algorithms, which have the ability for the conversion of text into a novel structure known as ciphertext. This is an encrypted type of the specified input as plain text that will not be read by unauthorized users. Likewise, by using a separate key, the encrypted data generates the algorithm to decrypt the data that can able to offer the original text to the authorized user (Li et al., 2017). In cloud environments, privacy maintenance comprises two aspects like data storage security and data processing security. Data storage security includes the problems of promising user data confidentiality when the data is saved in the data center. Data processing security includes the problems of how to preserve user confidentiality at runtime in a virtualized cloud platform. Numerous approaches are developed for the privacy preserving in the https://doi.org/10.1016/j.jksuci.2020.10.015 1319-1578/Ó 2022 Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Nomenclature Abbreviations Descriptions FHE Fully Homomorphic Encryption SMC Secure Multi-Party Computations ABSO Attribute-Based Signature Outsourcing CSP Cloud Service Providers SKMA-SC Suppressed K-Anonymity Multi-Factor Authentication Based Schmidt-Samoa Cryptography IoT Internet of Things CS Cloud Server IDP IoT-Oriented Data Placement NSGA Non-Dominated Sorting Genetic Algorithm SSO Shark Smell Optimization CPA Chosen Plaintext Attack JA Jaya Algorithm CDCs Cloud Data Centers NN Neural Network KPA Known Plain Attack J-SSO Jaya based Shark Smell Optimization PPR Privacy-Preserving Rate CC Computational Complexity SAW Simple Additive Weighting QoS Quality of Service MCDM Multiple Criteria Decision Making SFGA Shuffled Frog Leaping Algorithm and Genetic Algorithm BS-WOA Brain Storm based Whale Optimization Algorithm PSV-GWO Particle Swarm Velocity aided Grey Wolf Optimization GMGW Genetically Modified Glowworm OI-CSA Opposition Intensity-based Cuckoo Search Algorithm cloud sector. In Xie et al. (2018), the privacy-aware access control method has been proposed based on the Attribute Fuzzy Grouping named PriGuarder for enhancing the data privacy in the cloud sector. Still, the performance of the authentication is not effective. ABSO protocol is proposed in (Su et al., 2016) for protecting the user’s security and privacy in the cloud environment. However, the computational difficulty is extremely higher. The two main conventional approaches are based on either perturbation or cryptography approach. The perturbation-based method alters the data with noise for providing the protection (Belguith et al., 2018; Li, 2017). Conversely, the modification needs careful calibration for locating the model privacy and usability for improved stability. However, the privacy of the attributes is tackled with threats in security while dealing with plaintext. Perhaps, cryptography-based method is dependent on the FHE (Jiang et al., 2016) that has been advertized as a guaranteeing solution recently. This allows the encrypted data along with the public keys for uploading in the cloud service provider and SMC towards generating the encrypted intermediary outcomes (Gao et al., 2018; Mo et al., 2018). Currently, the data services provider may not access any user record while it doesn’t contain the secrete keys although it only provides as a computational platform (Liu et al., 2017). Privacy is still more complicated than security as it also needs to hold through CSPs. The huge amounts of personal data are exploited and analyzed by CSPs based on the cloud. If the CSP is considered to be trusted then in the cloud, the sensitive data handling is simpler (Li et al., 2017; Stergiou et al., 2018). Still, various legal problems are existing. However, the data subjects along with their personal or healthcare data trust the data controller in various cases, although they don’t permit the controller toward transferring the data by the trustworthy members. In contrast, the CSP may be under a jurisdiction different from the controllers. Moreover, to create the opportunity of legitimating the users’ data, various public CSPs provide their services at free cost. In recent years, numerous solutions are proposed for solving the above mentioned problems and to re-establish the user’s control and also for the data protection outsourced to the cloud (Behl, 2011). All of them entail masking sensitive data hence the protected values are saved in the cloud and the protected values are unmasked only by the user or controller who owns the data that are retrieved from the cloud. On the other hand, if the user needs to utilize both the cloud’s computational power and cloud’s storage, then it is more hard due to the protection of data, and it might be prepared well-suited with the outsourced computations on masked data on cloud premises (Ali et al., 2015; Choi and Lee, 2015). Therefore, there is a need for developing improved security model in the cloud. The major contribution of this paper is listed below. To implement the proposed privacy preservation model in the cloud with various datasets, such as Air quality, Concrete data, Heart disease, Super conductivity, and Whole sale customer data. To develop the efficient cloud data privacy preservation model with the data sanitization and restoration stages and using an optimal key generation approach. To implement a new meta-heuristic algorithm called J-SSO with the combination of JA and SSO. Here, the optimal key generation is optimized using the proposed J-SSO algorithm with the parameters like degree of modification, hiding ratio, and information preservation ratio. This paper is sequentially ordered as follows, Section 2 discusses the literature review. Section 3 explains the privacy cybersecurity model adopted for cloud data. Section 4 describes the data sanitization and restoration with optimal key generation. Section 5 defines the objective model derived for the developed cloud data cyber security. Section 6 discusses the experimental setup, and Section 7 concludes this paper. 2. Literature review 2.1. Related works In Praveena and Rangarajan (2018) have developed a new cloud service approach based on the integration of both public and private cloud and it was named as hybrid cloud service. Currently, for the cloud environment, the challenging issue was considered as a security due to hybrid cloud combination approach. In the literature, various security techniques were presented and these were not obtained at the adequate security level. Therefore, to solve this security issue, a novel machine learning application was developed to provide the security headed for the hybrid cloud networks during accessing and storing or retrieving the data. A new algorithm was implemented based on a dynamic access control mechanism called dynamic spatial role-based access control algorithm that was developed from the combination of Enhanced C4.5 and de-duplication processing algorithm. In addition, less than 5% of cloud users were denied access in comparison with the existing system and hence the security is enhanced by incorporating the cryptographic algorithm. It can be observed that the 2344 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 output was measured. Hence, the proposed framework had established better results based on MSCryptoNet. In Yan et al. (2020) offered the design and implementation of a node controller intended for a cloud energy storage network. For ensuring the security of the communication network, the system deployment procedures and function division were executed regarding the cloud energy storage scheme. Safety protection metrics were offered for the communication network demands that permitted the model for running stably and safely. The distribution capacity of the community was 1,260 kVA and the maximum load was ~ 250 kW. The total charging and discharging power of the energy storage equipment was ~ 90 kW and the permeability of the energy storage installation was 36%. After the installation of energy storage, the error rate of the load was decreased by 27.6%. Finally, results showed that the installation of energy storage can significantly reduce the load and differential rate. In Li et al. (2019) have implemented a new trust assessment structure named ‘‘STRAF” for the reputation and security of cloud services. This structure was facilitated by the trust assessment of cloud services so as to certify the cloud-based IoT context security through the reputation-based and security-based trust assessment approaches. The security of a cloud service was evaluated by using the cloud-specific security measures based on the security-based trust assessment approach. In the reputation-based trust assessment approach, the reputation of a cloud service was evaluated on the quality of cloud service by exploiting the feedback ratings. The QoS and reputation were typically represented by a comprehensive score reflecting the overall quality and opinion or by a small number of scores on several major aspects of performance. Experiments conducted using a synthesized dataset of security metrics and a real-world web service dataset show that the proposed trust assessment framework can efficiently and effectively assess the trustworthiness of a cloud service while outperforming other trust assessment methods. In Ali et al. (2020) have ‘‘reviewed the ISO 27002 Information Security standard” in the existing literature and established that individual awareness, compliance matters, and operational security was created for important government problems other than the process-oriented and the often-highlighted technical cloud security constraints. Theoretical cloud computing security constraint system was developed through four components such as compliance and legal requirements, data security, risk assessment, and technical and business requirements on cloud security so as to encourage a balanced view for governments. The cloud services were adopted by using model, hence the governments can employ jointly for demand uniform security constraints. Results from a comprehensive industry survey showed that 74% of participants highlighted that security was a major reason behind the low level of adoption of the cloud computing service model. In Sengupta et al. (2020) have proposed secure Fog-based advent of IIoT by suitably plugging a number of security features and by offloading some of the tasks judiciously to fog nodes. These features secure the system alongside by reducing the trust and burden on the cloud and resource-constrained devices. The benefits include scalability, agility, efficiency and decentralization. On the other hand the potential of fog computing was widespread as it reduced latency thereby reducing cost, and also provide better security. It consists of several limitations, huge computation and bandwidth cost to the data. Moreover, sharing the same data with multiple users require the sender to encrypt the data individually for each user. In Thanga Revathi et al. (2019) have introduced BS-WOA for identifying the secret key. It uses the fitness function for deriving the secret key, such that the privacy and the utility of the data were maintained as high as possible. One of the major advantages was that it had low number of parameters and lack of local optima performance of the proposed method has performed well when compared with the existing algorithm In Mohana Prabha and Vidhya Saraswathi (2020) have developed a new multifactor authentication known as SKMA-SC approach. This approach has included three key procedures such as authentication, data access, and registration. At the registration stage, the clients were registered with their individual identification data and securely save the information in CS by using suppression method. In a cloud environment, this was helped by SKMA-SC approach for preserving the client’s sensitive data from third parties or adversaries. At the authentication stage, the client’s identity was validated by the SKMA-SC approach regarding multi-factors like conditional attributes, one-time token, and password. Finally, during the data access stage, SKMA-SC approach permitted the clients for acquiring the requested data services while they were authorized for executing the Schmidt-Samoa data encryption or decryption procedure. By considering these stages, SKMA-SC approach was used to avoid the unauthorized access from the illegal party insecure communications in a cloud environment. SKMA-SC technique improves the PPR by 20% and 42% as compared to existing methods. The experimental result proves that SKMA-SC technique enhances the PPR and lessens the CC authentication. In Xiaolong et al. (2018) have developed an IDP approach with privacy preservation. Firstly, in the cloud data center, the fat-tree topology was analyzed with the data access time, energy consumption, and resource utilization. Further, by concerning IDP approach, the NSGA-II was implemented for achieving the energy saving, proficient high data access, and resource usage. In the meantime, privacy preservation of the IoT data was realized. Here, 50 experiments were conducted in the case of convergence for each dataset scale and multiple sets of results were observed. In order to pick out a relatively best solution, they had used SAW and MCDM to construct the utility function. Hence, the experimental analysis had proven the effectiveness and efficiency of the proposed method. In Tian et al. (2019) have presented a tailor-made public auditing scheme in fog-to-cloud based IoT scenarios, for data storage that could obtain the entire necessary performance and security constraints. In particular, a tag-transforming scheme based on the bilinear mapping technique was developed for converting the tags that were produced by mobile sinks to the ones formed using the fog nodes in the proof generation phase. It cannot efficiently protect the privacy of the identity, but in the verification phase, it also reduced the costs of communication and computation. Further, a zero-knowledge proof approach was designed for verifying the IoT data integrity from various generators whereas; it attained the exact data-privacy preserving. The results demonstrate that it can efficiently achieve secure auditing for data storage in fog-tocloud based IoT scenarios. From the experimental analysis, the proposed approach outperformed in terms of energy consumption, computation and communication costs in fog-to-cloud based IoT scenarios. In Kwabena et al. (2019) developed an MSCryptoNet, which was dependent on the multi-scheme FHE. This was implemented for the approximation of the activation function that was used in the CNN through low degree polynomials. This was important in the homomorphic encryption systems for the computations. The proposed system was targeted with the following cases such as (a) the encrypted inputs were practically estimated by the classifier with probable diverse encryption methods or even various keys whereas securing entire operations together with intermediate outcomes and (b) the reduction of computational cost and communication costs of the data providers. It measured the accuracy of the model for classification over encrypted data. The encrypted inputs were given to the trained network and the accuracy of the 2345 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 verification as well as the public audit ability. It also attains the complete security needs and the indispensable performance. But, the load balancing of various auditors is not handled and it also does not realize the effective auditing for the big data. Multi-scheme FHE (Kwabena et al., 2019) is encrypted with several keys or schemes and it can be used to train on various datasets and also the NN are relieved from efficiency as well as accuracy loss. Still, it cannot be applied practically. Network security protection technology (Yan et al., 2020) enhances the system load characteristics and runs the system stably and safely. It also provides better valley filling and peak-clipping effects. Yet, various risks related to the accounts management, security, and data protection occur. Security-based trust assessment method (Li et al., 2019) obtains the quantitative trustworthiness of the cloud services and the reputation. Here, the security is provided by the STRAF as complementary features. But, it cannot be performed in the real world and a working prototype is not constructed by this trust assessment framework. Conceptual cloud computing security requirements model (Ali et al., 2020) reduces the operational risks related to the privacy and security issues and using cloud computing security model, more benefits are provided to the government. Since the findings cannot be applied to regional local governments in various distinct countries with the same socio-economic conditions and it also cannot be applied to various sectors, industries, or countries. These challenges motivate to find a novel method for providing security in the cloud-related applications. entrapment, in solving clustering problems. The disadvantage was that the presence of a large number of users in the data pool, and hence, it was extremely difficult to maintain the privacy of every database. In Jyothi Mandala and Chandra Sekhara Rao (2019) have introduced PSV-GWO to find the optimal key. The key was optimally produced by the PSV-GWO method for data sanitization process. It was not easy to fall into the local optimum compared with other intelligent algorithms and had less parameter. It also poses some limitations, such as slow convergence, bad local searching ability, and low solving precision. In Annie Alphonsa and Amudhavalli (2018) have proposed GMGW to perform the sanitization process. It was used to perform the sensitive healthcare data sanitization and restoration process. It had significant benefits like consumption cost, application hosting, content storage as well as delivery. It can converge prematurely and be trapped into a local minimum especially with complex problems. In Shailaja and Rao (2019) have developed OI-CSA to find optimal key generation. It involves two phases, namely, data sanitization and data restoration. In both the sanitization and restoration processes, key extraction play a significant role, which was selected optimally using opposition intensity-based Cuckoo Search Algorithm, which was the modified format of Cuckoo Search Algorithm. It provided better runtime and scalability. However, there was no consideration on combination with web mining. The SSO has many significant benefits like; good convergence acceleration, fitting for wide search space, powerful neighborhood search characteristic, higher feasibility and efficiency in producing global optima. The advantage of JA includes faster computational speed, fast searching algorithm, and more memory storage. The drawback of SKMA-SC (Mohana Prabha and Vidhya Saraswathi, 2020) is that it does not enhance the confidentiality and data integrity level for different techniques in the cloud. The limitation of Public auditing scheme (Tian et al., 2019) include, that it is does not handle the load balancing of various auditors. The disadvantage of Multi-scheme FHE (Kwabena et al., 2019) is that it cannot be applied in a practical manner. The Security-based trust assessment method (Li et al., 2019) does not construct a working prototype and cannot perform in a practical cloud environment. 3. Proposed cybersecurity model adopted for cloud data 3.1. Developed architectural view Security in cloud computing is an important criterion to be addressed in the current researches. The data will be at high risk when the security measures are not offered correctly for data transmissions and operations. As cloud computing offers the ability for accessing the stored data to a set of users, there is a chance to have high risk for the data processing. Efficient security measures are required to be developed by identifying the security challenge and solutions for handling security limitations in cloud. If numerous organizations are sharing the resources then, there is a possibility of data misuse. Therefore, for avoiding the risk, it is necessary to protect the data archives and also the data, which entails process, transit, or storage. For avoiding the various limitations in the data security schemes in the literature, a novel cyber security model is designed for the cloud data. The architectural illustration of the proposed privacy preservation model for the cloud data is shown in Fig. 1. The proposed cyber security model uses the cloud data for analyzing the real time challenges. Datasets considered for the proposed cyber security model are Air quality, Concrete data, Heart disease, Super conductivity, and Whole sale costumer data, and these datasets are gathered from UCI repository. The two main phases of the proposed privacy preservation system are the data sanitization and data restoration. Data sanitization is the process of hiding the sensitive data or information in a cloud and hence intends to prevent it from leaking on to the unauthorized point. Furthermore, the proposed sanitization process is done based on the optimal key generation, and this process is improved by using the proposed hybrid meta-heuristic algorithm called J-SSO. The optimal key generation is regularized by considering a multiobjective function, which uses parameters such as information preservation ratio, hiding ratio, and degree of modification. By using this multi-objective function, the proposed J-SSO can efficiently execute the data sanitization and data restoration for cloud 2.2. Problem statement Cloud security protects the data, services, virtualized IP, and applications by means of a wide group of technologies, controls, and policies. But, it has various drawbacks such as loss of control, data loss, unsecured application programming interfaces, etc. There is a need to resolve these limitations in the future. Some of the major features and challenges are listed in Table 1. Machine Learning (Praveena and Rangarajan, 2018) restricts the access of the data depending on time and space. The security risks occurring in the hybrid cloud are minimized by machine learners. The cloud users are restricted from accessing the cloud data. Here, the secured storage is not provided using an effective cryptographic algorithm. SKMA-SC (Mohana Prabha and Vidhya Saraswathi, 2020) secretly stores the client’s personal information in the CS database. It also enhances the privacy-preserving rate by avoiding illegal access in the cloud. Still, the confidentiality and data integrity level are not enhanced for different techniques in the cloud and also, it does not use the function with signcryption. NSGA-II (Xiaolong et al., 2018) minimizes the energy consumption of CDCs. The access performance and the CDCs average resource utilization are also enhanced. Yet, it does not enhance the privacy constraints of the real –time IoT data and in the real physical environment, it cannot be implemented. Public auditing scheme (Tian et al., 2019) obtains the blockless 2346 Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 D. Ahamad, S. Alam Hameed and M. Akhtar Table 1 Features and challenges of state-of-the-art cloud security models. Author [citation] Methodology Praveena and Rangarajan (Praveena and Rangarajan, July 2018) Machine Learning Prabha and Saraswathi (Mohana Prabha and Vidhya Saraswathi, 2020) SKMA-SC Shucun et al. (Xiaolong et al., 2018) NSGA-II Fulin et al. (Tian et al., 2019) Public auditing scheme Zhen et al. (Owusu-Agyemang Kwabena; Zhen Qin ; Tianming Zhuang ; Zhiguang Qin, ‘‘MSCryptoNet: Multi-Scheme Privacy-Preserving Deep Learning in Cloud Computing”, IEEE Access, vol. 7, pp., 2019) Multi-scheme FHE Jialiang et al. (Yan et al., 2020) Network security protection technology Qixu et al. (Xiang Li ; Qixu Wang ; Xiao Lan ; Xingshu Chen ; Ning Zhang ; Dajiang Chen, ‘‘Enhancing CloudBased IoT Security Through Trustworthy Cloud Service: An Integration of Security and Reputation Approach”, IEEE Access, vol. 7, pp. 9368 - 9383, January, 2019) Shrestha et al. (Ali et al., 2020) Security-based trust assessment method Jayasree Sengupta et al. (Sengupta et al., 2020) Homomorphic Encryption BS-WOA S. Thanga Revathi et al. (Thanga Revathi et al., 2019) Conceptual cloud computing security requirements model Jyothi Mandala and M. V. P. Chandra Sekhara Rao (Mandala, 2019) PSV-GWO M. M. Annie Alphonsa and P. Amudhavalli (Annie Alphonsa and Amudhavalli, 2018) GMGW G.K. Shailaja and C.V. Guru Rao (Shailaja and Guru Rao, 2019) OI-CSA Features It minimizes the security risks occurring in the hybrid cloud. It restricts the data access on the basis of space and time. It restricts the cloud users from accessing the cloud data. It avoids the illegal access happening in the cloud thereby enhancing the privacy-preserving rate. It stores the personal information of the clients in the CS database in a secret manner. It enhances the access performance and the CDCs average resource utilization. It minimizes the CDCs consumption of energy. It achieves all the security needs and the indispensable performance. It attains blockless verification and public auditability. The NN are relieved from efficiency and accuracy loss. It can be trained on various datasets that are encrypted with several keys or schemes. It permits the system to run stably and safely. It enhances the system load characteristics. It provides better valley filling and peak-clipping effects. The STRAF provides both reputation and security as complementary features. It attains the quantitative trustworthiness of the cloud services. It provides more benefits to the government by means of a cloud computing security model. It reduces the operational risks for privacy and security issues. It reduces latency and provides better security. It has low number of parameters and lack of local optima entrapment, in solving clustering problems. It is not easy to fall into the local optimum compared with other intelligent algorithms. It has less parameter. Easy to run parallel computation. Have higher probability and efficiency in finding the global optima. It provides better runtime and scalability. Challenges It does not provide secured storage by means of an efficient cryptographic algorithm. It does not function with various cryptography techniques such as signcryption. It does not enhance the confidentiality and data integrity level for different techniques in the cloud. This technique cannot be implemented in the real physical environment. The privacy constraints of the real-time IoT data are not enhanced. The effective auditing for the big data is not realized. It does not handle the load balancing of various auditors. It cannot be applied in a practical manner. Various types of risks related to the accounts management, security, and data protection occur. The trust assessment framework does not construct a working prototype. It cannot perform in a practical cloud environment. It is not applied to various sectors, industries, or countries. The findings cannot be applied to regional local governments having same socioeconomic conditions in various distinct countries. High computation Bandwidth cost is high It is extremely difficult to maintain the privacy of every database. Bad local searching ability and low solving precision. Slow convergence. It can converge prematurely and be trapped into a local minimum especially with complex problems. Needs to improve privacy-preserving data mining 3.2.1. Air quality This dataset has 9358 instances of hourly averaged responses from 5 metal oxide chemical sensors array that are embedded in a device called an Air Quality Chemical Multisensor. The sensor is positioned at a most polluted area in an Italian city. It contains the recorded data from March 2004 to February 2005. It has various attributes like Time, reference analyzer, Absolute Humidity, Temperature, Date, and Relative Humidity. data. Data restoration is the process of revealing sensitive data by using the unique key that is used for the data sanitation process. 3.2. Dataset Description The proposed cyber security for the cloud data is done by gathering various datasets in UCI repository that are described below. The considered datasets and their links are given in Table 2. 2347 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 3.2.4. Super conductivity There are two files in the dataset, in which the features are extracted from the 21,263 superconductors. The number of attributes in this dataset is 81. The critical temperature is predicted using the extracted features. Multivariate dataset is considered here. 3.2.5. Whole sale costumer data In this dataset, the number of instances and attributes are considered as 440 and 8, respectively. Some of the attributes are fresh, grocery, frozen, milk, delicatessen, detergents_paper, region, Oporto, Lisbon, etc. 4. Data sanitization and restoration with optimal key generation 4.1. Data sanitization and restoration Data sanitization is the process of hiding the sensitive data or information in a cloud that intends to prevent the data from leaking on to the unauthorized point. On the other hand, restoration is the reverse process of the data sanitization process, which is carried out for evaluating the sanitization effectiveness. The flow diagram of data sanitization and restoration is shown in Fig. 2. During sanitization, the binary conversion is done for both the cloud data and the key matrix generation, where the proposed JSSO is used for generating the optimal key. The obtained binary data undergo XOR operation for achieving the sanitized data. Hence, from the original cloud data and the key matrix generation, the sanitized data is produced as mentioned in Eq. (1). Ds0 ¼ Ds Key2 ð1Þ 0 In Eq. (1), the sanitized data is denoted as Ds , the original data is represented as Ds, and the optimally generated key is termed as Key2 . As given in the objective function of the proposed cyber security model, the items Di are there for performing sanitization, and 0 Di are achieved after sanitization process. Therefore, the sensitive rules are hided in the sanitization process which is then transferred to the cloud. Hence, the data will be protected for further use, which can improve the performance of the security in cloud sector Fig. 1. Data sanitization and restoration using an optimal key generation. Table 2 Dataset description. Datasets Name of the datasets Links Dtaset 1 Air quality Dataset 2 Concrete data Dataset 3 Heart disease Dataset 4 Super conductivity Dataset 5 Whole sale customer data https://archive.ics.uci.edu/ml/datasets/Air +Quality: Access Date: 11–07-2020 http://archive.ics.uci.edu/ml/datasets/ Concrete +Compressive+Strength: Access Date: 11–07-2020 https://archive.ics.uci.edu/ml/datasets/Heart +Disease: Access Date: 11–07-2020 ‘‘https://archive.ics.uci.edu/ml/datasets/ Superconductivty+Data: Access Date: 11–07-2020” ‘‘https://archive.ics.uci.edu/ml/datasets/ Wholesale+customers: Access Date: 11–07-2020” 3.2.2. Concrete data This dataset contains a number of instances as 1030, number of attributes as 9, and attribute breakdown is divided into quantitative input variables as 8, and quantitative output variable as 1. Various variables such as Concrete compressive strength, Age, Blast Furnace Slag, Fly Ash, Fine Aggregate, Cement, Water, Coarse Aggregate, and Superplasticizer are used here. 3.2.3. Heart disease This dataset includes a number of attributes as 75, and the number of instances as 303. The attributes types like cigs, smoke, htn, chol, age, id, etc are considered in the dataset. Fig. 2. Solution encoding of key length using the J-SSO algorithm. 2348 Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 D. Ahamad, S. Alam Hameed and M. Akhtar Initialization of SSO Algorithm: Initially, odor particles are found at this step. If the shark smells any odor particle then the search process begins that is generally a fragile diffusion from prey or injured fish. This behavior is modeled by initializing the population based on the random manner within the specific search area that each of them denotes one odor particle. This establishes one probable location for the shark at initial search process. This is given in Eq. (5). without any cyber attacks. During restoration, the original data is recovered by using the same key using the proposed J-SSO. This procedure is given in Eq. (2). ^ ¼ Ds0 Key Ds 2 ð2Þ ^ represents the restored data. Here, the term Ds 4.2. Proposed key generation h In the proposed cloud data cyber security model, the key extraction plays a major role in both data sanitization and restoration process, where the optimization is done by the proposed J-SSO. The solution transformation is the first step for the key generation process, where the key Key is converted into a new form by Kronecker method. Here, Key is converted into Key1 by using Eq. (3), pffiffiffiffiffiffiffiffi in which the size is considered to be no00 Pmax . For example, for the Key ¼ f4; 5; 1g, the key matrix is given in Eq. (3). 3 4 4 4 6 7 Key1 ¼ 4 5 5 5 5 ð5Þ th initial S1j position vector is denoted as for the optimization problem, where j ¼ 1; 2; :::; PS, and the initial candidate solution is given in Eq. (6). h i S1j ¼ s1j;1 ; s1j;2 ; ::; s1j;ND th In Eq. (6), the j ð6Þ th shark position of the k dimension is repre- th th sented as s1j;1 , the k decision variable of the j individual is repre1 sented as sj , where k ¼ 1; 2; :::; ND, and the term ND is the number ð3Þ of decision variables in the optimization problems. In each position, the level of odor denotes their closeness to the fish or prey, which is mathematically formulated via objective function in SSO algorithm. A maximization problem is assumed without generality loss, where, if the objective function has a higher value like a stronger odor then the closer location towards the prey is considered as a better optimal candidate solution. In Eq. (3), the number of transactions is denoted as no, the nearest highest perfect square of no is termed as no00 and the maximum transaction length is mentioned as Pmax . Based on Eq. (3), the reconstructed key matrix Key1 is produced by executing rowwise duplication. Furthermore, the key matrix Key2 is generated by Kronecker method and it is given in Eq. (4). Key2 ¼ Key1 Key1 i Here, the population size is represented as PS. The j 2 ffi 1 1 1 ½pffiffiffiffiffi no00 P max S11 ; S12 ; S13 ; :::; S1PS ð4Þ 4.3.2. Movement of shark to prey In each position, the shark moves towards the prey with a velocity based on the stronger odor particles. Thus, related to the position vectors, the initial velocity vector PS is given in Eq. (7). Here, each velocity has elements in every dimension that is given in Eq. (8). In Eq. (4), the symbol represents the Kronecker product. The pffiffiffiffiffiffiffiffi size of Key2 is also considered as no00 P max . Here, the main contribution of the proposed cloud data security model is the optimization of key termed as Key using the proposed J-SSO algorithm. 1 Ve1 ; Ve12 ; ::; Ve1PS 4.3. Proposed J-SSO A new hybrid J-SSO algorithm is developed for the optimal key generation in the proposed privacy preservation model for cloud data. In this work, the proposed algorithm has hybridized the beneficial concepts of SSO, and JA. The benefits of SSO include better efficiency in solving the real-world optimization problems, provide the efficient way of changing the parameters, and provide better exploration ability at the initial searching process. The JA has many significant benefits like; easy to solve multi-objective optimization problems, find the optimal value in less time, and simple for developers. So, the proposed hybrid algorithm provides better performance than other bio inspired algorithms. Ve1j ¼ h v e1j;1 ; v e1j;2 ; ::; v e1j;ND ð7Þ i ð8Þ The direction of shark movement is changes based on the intensity of odor. If the concentration of odor is increased then the shark velocity also increases. This movement behavior is mathematically modeled with the gradient of the objective function. The direction of movement is illustrated in Eq. (9) when the objective function is enhanced via the highest rate. Veij ¼ gi : r1: rðof Þsij ð9Þ Here, i ¼ 1; 2; :::; imax and the objective function of the conventional SSO is given as of and its gradient is represented as rðof Þ. The term imax denotes the forward movement of shark, and it is separated into a number of stages, where the stage number is denoted as i. A constant value Veij is represented as the velocity of shark in each stage. The term gi is limited in the boundary of (Praveena and Rangarajan, 2018). A random number with uniform distribution is denoted as r1 and its value is in the range of (Praveena and Rangarajan, 2018). The velocity in each dimension is given in Eq. (10). 4.3.1. Conventional SSO (Abedinia et al., 2014) This is inspired by the searching behavior of shark towards their prey source based on the smell sense. In the search environment, the optimization procedure is created based on their search behaviors. Some hypothesizes are considered for the modeling of shark search behavior. Firstly, (a) if some fishes are injured or leaking the blood into the sea water or search environment, then the velocity of the fish mobility is low and the velocity of the shark’s is neglected. Thus, the prey is approximately fixed. Secondly, (b) when the blood is repeatedly infused to the sea water, then the water floods on distorting the odor particles are ignored. Further, if the closer odor elements are observed then the location of the prey is stronger. Hence, by observing the odor particles, the prey is approached by the shark. Thirdly, (c) there will be only one injured fish in the search environment of the shark. The sequential steps for the conventional SSO are given below. Veij;k ¼ gi : r1: @ ðof Þ i sj;k @sk ð10Þ The shark’s acceleration is limited because inertia of the shark. Therefore, their current velocity is based on the previous velocity that is shown in Eq. (11). 2349 D. Ahamad, S. Alam Hameed and M. Akhtar v eij;k ¼ gi : r1: @ ðof Þ i sj;k þ ai : r2:v ei1 j;k @sk Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 S0d;c;it ¼ Sd;c;it þ r1d;it Sd;best;it Sd;c;it r2d;it Sd;worst;it Sd;c;it ð11Þ Here, the momentum rate or inertia coefficient is termed as ai for range (Praveena and Rangarajan, 2018), and the value is a constant for stage i. Another random generator is r2 that is used to increase the search diversity. Before starting the search process, the initial velocity of shark is considered as v e1j;k for the first stage th Here, the value of d variable for the best candidate is termed as th Sd;best;it and the value of d variable for the worst candidate is termed as Sd;worst;it . The updated value of Sd;c;it is termed as S0d;c;it and th the two random numbers for d variable through the iteration it are termed as r1k;it and r2k;it , respectively in the range of (Praveena and Rangarajan, 2018). In Eq. (16), the term leaning of the solution to move nearer to the best solution is denoted as r1d;it Sd;best;it Sd;c;it and the tendency of the solution to avoid the worst solution is given as r2d;it Sd;worst;it Sd;c;it . When the bet- velocity, where v e0j;k is randomly fixed as small value or may be neglected. The velocity of shark can be increased up to a limit. The velocity limiter is used for the shark movement, which is given in Eq. (12). @ ðof Þ i i i1 i1 ; b : v e v ej;k ¼ min gi : r1: sj;k þ ai : r2:v ej;k j;k i @sk ð12Þ ter function value is given then S0d;c;it is acknowledged. At the end of iteration, all the function values are accepted and maintained. These are given as the input for the next iteration. Here, the velocity limiter ratio is termed as bi for stage i. The magnitude of v eij;k is achieved using Eq. (12), where the ‘‘min” 4.3.4. Proposed J-SSO algorithm The conventional SSO algorithm proves the better efficiency in solving the real-world optimization problems. This algorithm provides the efficient way of changing the parameters. It provides the better exploration ability at the initial searching process. However, it has limitations like it suffers from low convergence speed and also requires high time for convergence. These challenges may minimize the population range for escaping from the local optimal point. The aforementioned challenges are considered for developing the new algorithm with the combination of JA. The conventional JA has various features such as it is simple for developers and it has only one stage with few parameters. The conventional JA is employed for the multiobjective optimization problems. It is able to find the optimal value in less time. These features are considered for implementing the new algorithm called J-SSO. Here, in the proposed algorithm instead of rotational movement, JA updating is employed. In this proposed algorithm, a new formula is formulated for the gradient of the objective function of SSO termed as rðof Þ that is given in Eq. (17). operator is given as selected term. Due to the forward movement, the position of shark is represented as Piþ1 and it is established j based on their previous position and velocity, which is given in Eq. (13). Piþ1 ¼ Sij þ Veij : Dti j ð13Þ Here, the time interval of stage i is denoted as Dti , which is assigned as Dt i ¼ 1 for all stages for simplicity. Each component of v eij;k where ð1 6 i 6 NDÞ of the vector Veij is achieved from Eq. (12). For discovering the best candidate solutions, the shark develops a local search in each stage. This is formulated in Eq. (14). Q jiþ1;m ¼ Piþ1 þ r3:P iþ1 j j ð14Þ Here, the number of points in the local search of each stage is indicated as M, where m ¼ 1; 2; :::; M. Another random number is denoted as r3 with uniform distribution in the range of [1, +1]. The M point of the local search is Q iþ1;m in the vicinity of Piþ1 and j j these M points are connected for finding a closed contour equivalent to the rotational movement of shark. During the rotational movement, if shark discovers a point with stronger odor then the shark will move to that point and carry on the search path from that particular point. This behavior is simulated in Eq. (15). n o Sjiþ1 ¼ arg max of Piþ1 ; of Q iþ1;1 ; :::; of Q iþ1;M j j j ð16Þ rðof Þ ¼ abs of gbest of ðjÞ of gbest ð17Þ Here, the term of gbest denotes the fitness function of the best solution and the fitness function of the current solution is termed as of ðjÞ. Hence, if the obtained solutions are reaching the value of rðof Þ < 0:5 then the position update is done by SSO forward movement or else the position update is done by JA. The pseudo code of the J-SSO is depicted in Algorithm 1. ð15Þ The term Piþ1 is acquired from forward movement and from the j is obtained, and Siþ1 is the next posirotational movement Q iþ1;M j j tion of the shark that is chosen based on the candidate solution through the highest of value. The series of rotational and forward movements is sustained until i attains imax . For the optimization problem, the best individual achieved in the final stage is chosen as the SSO solution. Algorithm 1: Proposed J-SSO Initialize shark population Set the user defined parameters Initialize stage counter as i ¼ 1 for i ¼ 1:imax if rðof Þ < 0:5 Update velocity vector based on SSO using Eq. (12). Update position based on SSO using Eq. (13). Else update solution based on JA using Eq. (16) end if end for i Set i ¼ i þ 1 Choose the best position of shark at last stage that has the highest of value End 4.3.3. Conventional JA (Venkata Rao, 2016) It is a powerful optimization algorithm for solving the unconstrained and constrained optimization issues. The conventional JA has only one stage and it is easy to implement. This conventional JA requires only common control parameters. Let the number of design variables are selected as de, where d ¼ 1; 2; . . . ; de at every iteration it. The number of candidate solutions is termed as cs where c ¼ 1; 2; . . . ; cs. Let the best candidate and the worst candidate is termed as best and worst, respectively. The best value of f ðsÞ and the worst value of f ðsÞ are achieved in the entire candidate solutions. Furthermore, if the value of the variable th is denoted as Sd;c;it for d variable in the cth candidate through the th iteration it , then the value designed by the Eq. (16). 2350 Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 D. Ahamad, S. Alam Hameed and M. Akhtar The hybrid optimization concept is inspired from the combination of various optimization rules or techniques. It has been proven that the better results for the definite search problems. The hybrid optimization algorithms have been proven to obtain better convergence by utilizing various optimization principles (Marsaline Beno et al., 2014). Fig. 3. Analysis on Degree of Modification of the proposed cyber security for cloud data using (a) Dataset 1, (b) Dataset 2, (c) Dataset 3, (d) Dataset 4, and (e) Dataset 5. 5.5 Final objective function 5. Objective model derived for the developed cloud data cyber security The optimal key generation is achieved using the multiobjective function for the proposed cloud data cyber security model by considering three parameters like degree of modification, hiding ratio and information preservation ratio as given in Eq. (22). 5.1. Degree of modification The degree of modification is described as ‘‘the degree of modification happened between the original dataset Ds and sanitized data set Ds0 that is measured by finding the Euclidean distance among Ds and Ds0 ”. The degree of modification is mathematically formulated in Eq. (18). F 1 ¼ Ds Ds0 Ob ¼ F 1 þ ð1 HRÞ þ ð1 PRÞ ð22Þ Here, the terms HR,PR, and F 1 represents the hiding ratio, the information preservation ratio, and the degree of modification, respectively. ð18Þ 6. Experimental setup 5.2. Hiding ratio 6.1. Simulation setup Hiding Ratio is defined as ‘‘the rate of sensitive items that are correctly hided in Ds0 ”. This is used to find the index of value to be hidden. The term D1 is considered as the difference between the original data of the corresponding index, and the term D2 is considered as the difference between the sanitized data of the corresponding index. The difference among D1 and D2 is given in Eq. (19). Ddiff ¼ abs ðD1 D2 Þ The proposed cloud data cyber security model was implemented in MATLAB 2018a, and the analysis was carried out extensively for various security measures. The MATLAB has many significant benefits like, easy to develop computational codes, debug easily, and performs extensive data analysis and visualization. For handling the cloud data, MATLAB offers an unparalleled environment to quickly develop and leverage various technologies to build complete solutions. For conducting the experiments, the maximum iteration was considered as 100 and the population size was represented as 10. Five datasets were gathered for the experiments that were given in Table 2. Here, the performance of the proposed model was compared over the conventional models based on statistical analysis, convergence analysis, analysis on KPA and CPA attacks, and key sensitivity analysis. The proposed J-SSO algorithm was compared with the conventional optimization algorithms like PSO (Bonyadi and Michalewicz, 2016), GWO (Nirmala Sreedharan et al., 2018), JA (Venkata Rao, 2016), and SSO (Abedinia et al., 2014). The optimal key generation is done by obtaining a multi-objective function, which considers parameters such as degree of modification, hiding ratio, and information preservation ratio. The degree of modification shows that the information loss happened in sanitized data when used along with the original data. Hiding rate shows the effectiveness of the algorithm in hiding the sensitive data and non-hiding the other data by preserving the information. Analysis on these metrics shows the ability of the algorithm in data sanitization and restoration with optimal key generation, so that the algorithm confirms the security in all types of cloud data. ð19Þ Consider, L1 as the length of the non-zero indexes of Ddiff and the mathematical formula for hiding ratio is equated in Eq. (20). HR ¼ L1 Ti ð20Þ In Eq. (20), the total number of data indexes that have to be hided is termed as Ti. The hiding ratio should be maximized for the best performance. 5.3. Information preservation ratio Information preservation ratio ‘‘is defined as the rate of nonsensitive rules not hiding in Ds0 . The information preservation ratio is the reciprocal of information loss”, which is given in Eq. (21). PR ¼ L2 Tp ð21Þ In Eq. (21), the number of zero indexes is termed as L2 and the total number of data indexes that have to be preserved is termed as Tp. The preservation ratio should be maximized for the proposed cyber security model. 6.2. Analysis on degree of modification 5.4. Solution encoding The degree of modification is analyzed for various datasets using diverse optimization algorithms via distance and iterations as given in Fig. 4. As mentioned earlier, the degree of modification is the Euclidean distance between the original and the sanitized data. It shows the information loss happened in sanitized data when correlated along with the original data. The degree of modification of the sanitized data should be minimum, which ensures that there is no information loss during the sanitization approach. The proposed J-SSO algorithm is producing minimal distance than The proposed J-SSO algorithm is used for the optimization of key for performing data sanitation and restoration. Based on the size of the data or number of transactions, the length of key is changed. The solution encoding of the key generation process is given in Fig. 3. Here,ni ¼ 1; 2; :::; no, in which the no denotes the length of the field or attribute. The bounding limit is given from 1 to 26 1. The key vectors are optimized using the J-SSO algorithm for generating the best solution. 2351 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Fig. 4. Analysis on Preservation Ratio of the proposed cyber security for cloud data using (a) Dataset 1, (b) Dataset 2, (c) Dataset 3, (d) Dataset 4, and (e) Dataset 5. enhanced than PSO, GWO, JA, and SSO, respectively at iteration 100. Similarly, for all the datasets the proposed J-SSO algorithm has outperformed conventional algorithms regarding the preservation of relevant data in cloud. conventional algorithms for all the iterations from 0 to 100. At iteration 100, J-SSO is 84% better than PSO and GWO, 83% better than JA, and 80% better than SSO for dataset 1. For dataset 5, the proposed J-SSO algorithm is 60%, 5%, 78%, and 70% enhanced than PSO, GWO, JA, and SSO, respectively at iteration 100. Therefore, the proposed J-SSO algorithm is performing well than conventional algorithms in terms of degree of modification for securing cloud data. 6.4. Convergence analysis The proposed J-SSO algorithm is analyzed based on the convergence for all the datasets with the conventional algorithms, which is depicted in Fig. 6. For dataset 2, the proposed J-SSO is 95% better than PSO and SSO, and 96% better than GWO, and JA. Similarly, for dataset 5, it is 52%, 73%, and 66% enhanced than PSO, JA, and SSO, respectively at iteration 100. Hence, the proposed algorithm shows the better convergence in attaining the multi-objective function for securing the cloud data. 6.3. Analysis on preservation ratio The preservation ratio is analyzed for various datasets and they are represented in Fig. 5. The enhanced preservation ratio of the proposed J-SSO algorithm is observed for all the datasets and compared against conventional algorithms for various iterations. For dataset 3, the proposed J-SSO algorithm is 87.5%, 50%, 90%, 2.5% 2352 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Fig. 5. Convergence Analysis of the proposed cyber security model for cloud data using (a) Dataset 1, (b) Dataset 2, (c) Dataset 3, (d) Dataset 4, and (e) Dataset 5. 6.5. Comparative analysis over literature bio-inspired models 6.6. Analysis on KPA and CPA attacks The proposed J-SSO algorithm is analyzed against the performance of the bio-inspired algorithms in the literature works for all the datasets, and it is depicted in Fig. 7. For dataset 1, when the iteration is 60, the proposed J-SSO is 72% better than BSWOA, 78% better than PSV-GWO, 83% better than GMGW and 73% better than OI-CSA. For dataset 4, when the iteration is 80, the proposed J-SSO is 85% superior to BS-WOA, 88% superior to PSV-GWO, 86% superior to GMGW and 83% superior to OI-CSA. Similarly, for dataset 5, when the iteration is 80, the proposed JSSO is 97%, 96%, 98% and 95% enhanced than BS-WOA, PSV-GWO, GMGW, and OI-CSA, respectively. Hence, it is confirmed that the improved J-SSO is effective for securing the cloud data when compared with related works. CPA is described as ‘‘an attack model for cryptanalysis which presumes that the attacker can obtain the ciphertexts for arbitrary plaintexts”. KPA is ‘‘an attack model for cryptanalysis where the attacker has access to both the plaintext, and its encrypted version”. The effect on KPA and CPA attacks on various algorithms for different datasets is given in Table 3. In this section, the correlation among the original and restored data is analyzed when the CPA attack is done. Similarly, when the KPA attack is carried out, then correlation among the original and restored data is analyzed. During CPA and KPA attack, the correlation between the restored data and original data becomes minimum. For data set 4, the correlation of the proposed J-SSO is 0.11%, 0.07%, 0.16, and 0.159 improved than PSO, GWO, JA, and SSO, respectively. For data set 2353 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Fig. 6. Comparative analysis of the proposed model with related works for securing the cloud data using (a) Dataset 1, (b) Dataset 2, (c) Dataset 3, (d) Dataset 4, and (e) Dataset 5. 1, the correlation of the proposed J-SSO is 0.2% superior to PSO, GWO, JA, and SSO, respectively against CPA attack. Hence, the proposed algorithm has performed well and shown the enhanced efficiency against attacks than the conventional algorithms for securing the cloud data. ian of the J-SSO is 53%, 67%, 69%, and 66% superior to PSO, GWO, JA, and SSO, respectively. The Standard deviation of the J-SSO is 47%, 6%, 31%, and 37% superior to PSO, GWO, JA, and SSO, respectively. Thus, the proposed J-SSO has shown the enhanced performance than the conventional algorithms. 6.7. Statistical analysis 6.8. Key sensitive analysis In Table 4, the statistical analysis of various datasets is given. Due to the stochastic nature of the algorithms, every algorithm is required to be executed 5 times in terms of various measures like best performance, worst performance, mean, median, standard deviation. For dataset 2, the mean of the J-SSO is 42%, 57%, 61%, and 60% superior to PSO, GWO, JA, and SSO, respectively. The med- The performance of the extracted key is analyzed for various percentage changes. Here, 10%, 20%, 30%, 50%, and 70% changes are executed for evaluating the key sensitivity, which is given in Table 5. The analysis provides the correlation between the restored data and original data, which should be minimum for changes in key. For dataset 4, at 70% changes in the key, it is 2354 Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 D. Ahamad, S. Alam Hameed and M. Akhtar Fig. 7. Proposed architecture of cloud data cyber security model. Table 3 Effect on KPA and CPA attacks for various datasets in cloud. Algorithms Dataset 1 Dataset 2 Dataset 3 Dataset 4 Dataset 5 KPA attack PSO (Bonyadi and Michalewicz, 2016) GWO (Nirmala Sreedharan et al., 2018) JA (Venkata Rao, 2016) SSO (Abedinia et al., 2014) Proposed J-SSO 0.99998 0.99992 0.99998 0.99999 0.99997 0.99999 0.99988 0.99959 0.99991 0.99759 0.99698 0.9983 0.99972 0.99979 0.99498 0.9993 0.99889 0.99972 0.99974 0.99815 0.99999 1 1 1 0.99799 CPA attack PSO (Bonyadi and Michalewicz, 2016) GWO (Nirmala Sreedharan et al., 2018) JA (Venkata Rao, 2016) SSO (Abedinia et al., 2014) Proposed J-SSO 0.99999 0.99999 0.99999 0.99999 0.99799 1 0.99995 0.99995 0.99999 0.99795 0.99993 0.99986 0.99994 0.99993 0.99786 0.99995 0.99992 0.99997 0.99998 0.99992 1 1 1 1 0.998 6.9. Comparative analysis over MSCryptoNet (Kwabena et al., 2019) 71% and 67% PSO and GWO, respectively. For dataset 3, at 30% changes in the key, it is 1.2%, 14%, 36%, and 1.09% PSO, GWO, JA and SSO, respectively. Therefore, the proposed algorithm has shown the better performance for the key sensitivity analysis. The comparative analysis of the proposed J-SSO for securing the cloud data is compared with the MSCryptoNet and it is shown in Table 6. For dataset 1, 2, 3, 4, and 5 the proposed J-SSO is 28.3%, 2355 D. Ahamad, S. Alam Hameed and M. Akhtar Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 Table 4 Statistical analysis on various datasets for proposed cloud data security. Measures PSO (Bonyadi and Michalewicz, 2016) GWO (Nirmala Sreedharan et al., 2018) JA (Venkata Rao, 2016) SSO (Abedinia et al., 2014) Proposed J-SSO Dataset 1 Best Worst Mean Median Standard deviation 12.917 15.632 14.47 15.237 1.2488 15.237 15.736 15.339 15.237 0.2223 9.7998 17.284 15.088 16 3.0657 11.608 19.22 17.187 18.447 3.1811 2.5918 8.4012 4.3883 3.6427 2.2985 Dataset 2 Best Worst Mean Median Standard deviation 0.94072 6.4628 4.2533 4.4961 2.024 4.4578 6.6864 5.7156 6.4628 1.1343 5.3572 7.0371 6.3388 6.7868 0.80731 5.4146 7.1643 6.2782 6.2809 0.77601 1.4369 3.7535 2.4564 2.0879 1.0656 Dataset 3 Best Worst Mean Median Standard deviation 1.1022 3.7543 2.1525 1.7947 1.1131 0.55068 0.57555 0.56557 0.56442 0.009693 0.61149 2.6038 1.2709 0.8682 0.80661 1.5107 2.3195 1.9279 1.9932 0.37934 0.52962 0.57451 0.5518 0.55068 0.015914 Dataset 4 Best Worst Mean Median Standard deviation Best 3.5987 19.125 16.016 19.118 6.9414 3.5987 5.2544 30.186 11.864 6.6603 10.545 5.2544 4.3378 12.384 8.8163 10.159 3.3909 4.3378 4.2552 15.593 8.1586 6.0941 4.6798 4.2552 3.6033 3.6473 3.6245 3.624 0.015563 3.6033 Dataset 5 Best Worst Mean Median Standard deviation 1.1191 6.5336 2.5551 1.499 2.2553 0.67953 0.71822 0.69816 0.70192 0.01577 0.84149 3.5954 2.5193 2.5423 1.1269 1.6645 2.7892 2.1414 2.1034 0.4968 0.68512 0.72109 0.69289 0.68512 0.01581 Table 5 Key Sensitive Analysis on various Datasets for the proposed cloud data security. Percentage PSO (Bonyadi and Michalewicz, 2016) GWO (Nirmala Sreedharan et al., 2018) JA (Venkata Rao, 2016) SSO (Abedinia et al., 2014) Proposed J-SSO Dataset 1 10 20 30 50 70 0.99783 0.99941 0.98441 0.99364 0.99939 0.99987 0.99782 0.06289 0.40021 0.19573 0.7314 0.3182 0.99792 0.98905 0.99703 0.99372 0.99865 0.99731 0.64393 0.99515 0.95447 0.99372 0.9827 0.24289 0.43499 Dataset 2 10 20 30 50 70 0.99763 0.99563 0.99444 0.99229 0.063081 0.99916 0.3111 0.18802 0.38059 0.98245 0.99251 0.97842 0.022587 0.95736 0.48956 0.75247 0.9965 0.97948 0.9822 0.074526 0.99969 0.98357 0.9987 0.73574 0.15383 Dataset 3 10 20 30 50 70 0.78208 0.88274 0.85458 0.52012 0.81045 0.89968 0.92424 0.98892 0.80295 0.29649 0.90693 0.98576 0.61996 0.83413 0.5028 0.94484 0.43935 0.86063 0.71961 0.85674 0.00604 0.99058 0.84422 0.52048 0.39555 Dataset 4 10 20 30 50 70 0.50446 0.9187 0.65577 0.90332 0.60003 0.94688 0.6714 0.87048 0.42983 0.53903 0.62869 0.08622 0.40617 0.60069 0.56664 0.94629 0.79409 0.52633 0.77527 0.58136 0.66323 0.66716 0.66457 0.22032 0.17283 Dataset 5 10 20 30 50 70 0.99918 1 0.99997 0.99999 0.99001 0.9987 1 0.99999 0.99998 0.99998 1 0.99998 0.99999 1 0.99968 0.99999 1 0.99949 0.99995 0.99993 0.9997 0.99998 0.9996 0.99207 0.99991 2356 Journal of King Saud University – Computer and Information Sciences 34 (2022) 2343–2358 D. Ahamad, S. Alam Hameed and M. Akhtar tage of GMGW is that the accuracy of restoration seems to be very low. Moreover, the techniques OI-CSA and BS-WOA suffer from low convergence behavior in maintaining the privacy of every database. Moreover, the proposed J-SSO keeps its ability in solving the multi-objective privacy preservation problem with fast convergence rate and attained better results while dealing with different attacks and varied keys, and is proved to be computationally efficient that other methods. From the analysis, for dataset 5, proposed J-SSO is 52%, 73%, and 66% enhanced than PSO, JA, and SSO, respectively at iteration 100.Therefore, the proposed algorithm has shown better performance through statistical analysis, convergence analysis, analysis on KPA and CPA attacks, and key sensitivity analysis over the conventional algorithms. Cloud security application is a series of identified processes, controls, and technology managing all information exchanges that happen in collaborative cloud environments like Microsoft Office 365, Google G Suite, and Slack. Moreover, the cloud computing paradigm plays a vital role in many applications like, like resource allocation, scheduling, energy management, virtualization, and security, and these areas are intertwined with many optimization problems like the proposed model. Table 6 Comparative analysis of the proposed model over MSCryptoNet for securing the cloud data. Dataset MSCryptoNet (Kwabena et al., 2019) Proposed J-SSO Air quality Concrete data Heart disease Super conductivity Whole sale customer data 0.52844 0.54957 0.75202 0.54468 0.587 0.67844 0.74957 0.90202 0.74468 0.837 Table 7 Computational time of the proposed and existing methods for securing the cloud data. Methods Computational time(sec) PSO (Bonyadi and Michalewicz, 2016) GWO (Nirmala Sreedharan et al., 2018) JA (Venkata Rao, 2016) SSO (Abedinia et al., 2014) BS-WOA (Thanga Revathi et al., 2019) PSV-GWO (Mandala, 2019) GMGW (Annie Alphonsa and Amudhavalli, 2018) OI-CSA (Shailaja and Guru Rao, 2019) MSCryptoNet (Kwabena et al., 2019) Proposed J-SSO 142.38 159.11 159.24 160.26 128.85 133.13 133.33 134.78 272.38 129.47 Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. 36.3%, 19.9%, 36.7%, and 42.5% superior to MSCryptoNet. Hence, it is confirmed that the improved J-SSO is effective for securing the cloud data when compared with MSCryptoNet. References 6.10. 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Comput. 65 (6), 1964–1977. The computational time of the proposed and existing methods is analyzed and listed in Table 7. The computational time of the proposed J-SSO is 9.06% better than PSO, 18.62% better than GWO, 18.69% better than JA, 19.21% better than SSO, 0.48% worst than BS-WOA, 2.74% better than PSV-GWO, 2.89% better than GMGW, 3.93% better than OI-CSA, and 52.4% better than MSCryptoNet respectively. Eventhough, the computational time of the proposed method is lesser than one of the existing method, the performance in securing the cloud data seems to be better when compared over all the existing methods. 6.11. Time complexity of the proposed method using big O notation Big O notation is the most common metric for calculating time complexity. Big O specifically describes the worst-case scenario and can be used to describe the execution time required or the space used by an algorithm. The time complexity of the proposed J-SSO is Oðit PS ^ 2Þ, where, PS is the population size and it is the maximum iterations. The Space complexity of the proposed J SSO is O it PS2 . 7. Conclusion The proposed privacy preservation model has been implemented specifically for the cloud sector. The proposed model involved two main steps, like data sanitization and restoration with optimal key generation. The optimal key was optimized using the proposed J-SSO algorithm by deriving a multi-objective function with the parameters like the degree of modification, hiding ratio, and information preservation ratio. While considering the state-of-the-art meta-heuristic algorithms for solving the privacy preservation problem in handling numerous data, PSV-GWO faces bad local searching ability, and slow convergence. The disadvan2357 D. Ahamad, S. Alam Hameed and M. 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