The data security challenges to design new protocols are never ending due to rapid increase of various network devices especially in the 5G paradigm where a huge amount of data is generated and transmitted. A self-optimizing hybrid encryption scheme has been proposed based on the multiple dynamic keys, which has an autonomy to select the data block size to circumvent heat dissipation. Three different data lengths, i.e., 128, 512 and 2048 bits have been taken for encryption with two fixed and variable key lengths. Four different cases have considered; (a) a fixed key length (32 bits) and re-encryption is done with dynamic key length (32–64 bits), (b) 32–64 bits first keys are used for encryption and re-encryption is done with fixed key length (32 bits), (c) a fixed key length (64 bits) and re-encryption is done with dynamic key length (32–64 bits), and a fixed key length (32–64 bits) and re-encryption is done with dynamic key length (64 bits).