One of the principal challenges of resource sharing on data communication network is its security. This is premised on the fact that once there is connectivity between computers sharing some resources, the issue of data security becomes critical. This paper presents a design of data encryption and decryption in a network environment using RSA algorithm with a specific message block size. The algorithm allows a message sender to generate a public keys to encrypt the message and the receiver is sent a generated private key using a secured database. An incorrect private key will still decrypt the encrypted message but to a form different from the original message.