When designing a communication system, security becomes the main issue for secure transmission of information or data. Therefore, data encryption technique is used to protect data transmission during the communication process. Data encryption generally interprets data into a different form, or encryption, so that the person in possession of a secret key (i.e. a decryption key) or password can access that data. Subsequently, another question arises regarding the choice of the encryption algorithm to apply depending on the type of data. The complexity detector is mainly used to determine the complexity of the data to be transmitted. A threshold value is set against which the sensitivity of the data is measured and then the appropriate encryption algorithm is used depending on the sensitivity of that particular data. Cryptography