Omolehin, Joseph OAbikoye, Oluwakemi CJimoh, Rasheed G2018-06-132018-06-132008Omolehin, J.O., Abikoye, O.C. & Jimoh, R.G. (2008): Development of data encryption and decryption algorithm using 4 – row Rail Fence Cipher. Journal of the Nigerian Association of Mathematical Physics. . vol 13; 411-416, Published by Nigerian Association of Mathematical Physicshttp://hdl.handle.net/123456789/460The increase use of electronic means of data transfer from one point to the other coupled with growth in networking and internet has really called for vital security. This security is usually achieved by encryption and digital signature. Data encryption is the automated process of securing data so that no unauthorized person can access them It makes use of different algorithm to scramble (encrypt) the original message called plain text into an unintelligible message called cipher text. Key is an important object in data encryption. There are some data encryption algorithm that uses same key for both its encryption and decryption while some uses two keys, one for encryption and the other for decryption. Rail fence cipher is categorized under data encryption algorithm that uses same key for both its encryption and decryption. The number of rows used to break up text/data to be encrypted into rows and column arrangement serves as the key in Rail fence cipher. In this paper, we present the algorithm that can encrypt and decrypt data using a 4-row Rail fence Cipher.enEncryptionRow.DecryptionCipher textalgorithmRail Fence cipherPlain textArticle