Cloud computing is a computing paradigm that offers several benefits such as scalability, reduced cost, mobile storage, ubiquitous access and energy saving. It is also faced with several challenges dominated by security, trust and privacy. Particularly, security challenges such as data security has been considered as a serious bottleneck and has impeded several individuals and organizations from migrating their businesses and data to the cloud. Users� data integrity and confidentiality are prone to unauthorized access and compromises. Albeit several solutions have been offered such as data encryption, cloud-end users� data is still at risk. Encryption has several algorithms either symmetric or asymmetric with each having its own strengths and weaknesses. However, due to the sophistication of today�s attacks, using individual algorithm is no longer sufficient to protect users� data and identifying which combination of the algorithms to use in reinforcing security strength at reduced computational and resource usage cost poses a challenging task. Therefore, this paper analyses the state-ofthe- art of encryption algorithms used for data encryption in cloud environment with the goal of identifying their strengths and weaknesses. We analyzed ten (10) articles which utilized hybrid algorithms with emphasis on 3 symmetric and 3 asymmetric algorithms. The analysis results shows that the symmetric techniques are mostly computational and resource-efficient than the asymmetric techniques. However, the asymmetric technique is considered a better option for data security to ensure users� data confidentiality and integrity. Furthermore, this paper proposes a 3-tier RSA-Blowfish-DES hybrid model to protect users� data stored in the cloud. The model was designed, developed and performance evaluated against a 2-tier RSABlowfish hybrid model. The evaluation was based on the security strength, time efficiency and the data size after encryption and decryption. The evaluation shows that both hybrid models were effective in the protection of data stored in the cloud compared to individual algorithms. The 2-tier model has a better time efficiency than the 3-tier model, while the data size was observed to slightly increase after encryption but assumed its original size after decryption. Nonetheless, the 3-tier RSA-DES-Blowfish model was found to be more secured. Consequently, the 3-tier model could be more preferable in ensuring the confidentiality and integrity of cloud users� data which in turn will reduce or eliminate existing skepticism about security of data stored in cloud.

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