A method and system that modularizes a message by separating the message definition data from the message data. The message definition data and message data are transmitted over a secure channel to a target computing device. The message definition data and message data are recombined to form the original message at the target computer using a process corresponding to the modularization process. A key is used to track the associated definitions and message data and determine the corresponding combination process. Separate transmission of the data definitions and message data provides an added level of security. If message data is intercepted and decrypted by a third party, then the data is not easily utilized, because the definition data is absent. Similarly, interception of the message definition is not useful without the message data.