the mitigating of the energy consumption, would be considerably high.

Authenticated Encryption with Associated Data {#AEAD}
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The Authenticated Encryption with Associated Data (AEAD) is used in *ExTru* for the transmission of the CSTN-RCSTN configuration (TRN). Authenticated ciphers incorporate the functionality of confidentiality, integrity, and authentication. The input of an authenticated cipher includes *plaintext* (message), *associated data* (AD), *public message number* (NPUB), and *secret key*. Then, the *ciphertext* is generated as a function of these inputs. A *tag*, which depends on all inputs, is generated after message encryption to assure the integrity and authenticity of the transaction. This tag is then verified after the decryption process. The choice of AEAD could significantly affect the area overhead of the solution, the speed of encrypted communication, and the extra energy/power consumption. To show the performance, power/energy, and area trade-offs, we employ two AEAD solutions: a NIST compliant solution (AES-GCM) [@dworkin2007sp], and a promising lightweight solution (ACORN) [@wu2016acorn].

AES-GCM is the current National Institute of Standards and Technology (NIST) standard for authenticated encryption and decryption as defined in [@dworkin2007sp]. ACORN is one of two finalists of the Competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR), in the category of lightweight authenticated ciphers, 