On each square matrix, we first apply displacement method, which changes the position of characters in the string, and then add expanded matrix, which hides the number of occurrences and values of characters. The algorithm focuses on breaking the input string into a large number of small sized square matrices, whose size varies from 1x1 to 9x9.

The proposed algorithm is a symmetric algorithm. This research provided analysis and investigation of these encryption algorithms in light of components of the designs, versions of these algorithms, encryption keys, block size, round functions, and the techniques used in the designs. In this paper, we proposed some encryption algorithms to tackle the issue of data confidentiality in the IoT applications. In this context, the saved data and exchanged data required protection against hacking operations, transferred with more secure communications channels, and safe storage environment in the clouds and local storage systems. These smart devices relied on data exchange and data storage resources in clouds computing services. For instance, some devices such as Notebooks and smartphones have been used to perform different management activities and duties. Furthermore, the IoT with smart devices adopted in various companies, organizations, and public services systems. The IoT included a variety of components and devices such as radio frequency identification devices, wireless sensors, actuators, and wireless networks. cloud services, smart environments, logistics, social and personal domains, and health-care services). In the past years, the internet of things (IoT) used in different applications and very wide range of fields (e.g. On the basis of experiments, it is concluded that Caesar cipher the best amongst the algorithms selected for the implementation. All the algorithms are implemented in C++ language using QT creator, so that a fair comparison of execution speeds can be done. In this paper, 7 classical substitution algorithms i.e., Affine, Atbash, Caesar, Modified Caeser Baconian, Polybius square and Letter number ciphers are implemented, and their performance is compared by encoding input files of various sizes on LINUX platform. So, there is always a deemed necessity to analyze, standardize and represent these algorithms to the future researchers and struggling students so that they can learn to design effective and innovative techniques for securing data. But, the performance and cost implementation of the algorithms are also those factors which we cannot ignore. The principle objective guiding the design of any cryptographic algorithm must be the security it provides against unauthorized attack. Cryptography emerged as a solution has reserved its unvanquishable place in the field of security. with the rapid development in the technology, the call for security has also raised its pitch and Information Security has become an important issue during last decades. The work can be considered significant in the field of encrypting databases because the repetition of encrypted data inside databases is considered an important vulnerability that helps to guess the plaintext from the encrypted text. The proposed technique is robust against disclosing the repetition encrypted data based on the result of Avalanche Effect in an accepted ratio (62%) and the results of the output of the proposed encryption method have acceptable randomness based on the results of the p-values (0.629515) of the National Institute of Standards and Technology (NIST) randomness tests.

Where, all elements that uses were polynomial numbers of a finite field of degree Galois Fields GF (2 8).

In the hiding stage, the ciphertext was hidden into a 16×16 matrix that includes 16 sub-magic squares to eliminate the duplicates in the ciphertext. Two techniques of encrypted and hiding were executed in the encryption stage by using a magic square size 3×3 and Latin square size 3x3 to providing more permutation and also to ensure an inverse matrix of decryption operation be available. Therefore, the proposed method was established to prevent the attackers from exploiting the vulnerabilities of the redundancy in the ciphertext and enhances the substitution and permutation operations of the encryption process the solution was performed by eliminates these duplicates by hiding the ciphertext into a submatrix 4x4 that chooses randomly from magic square 16x16 in each ciphering process. Hackers should be prevented from disclosing sensitive data when sent from one device to another over the network.

Decrypt polybius square