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Advanced Encryption Standard (AES)

AES (Advanced Encryption Standard) is a symmetric encryption algorithm, meaning the same key is used for both encryption and decryption of data. It operates on fixed-size blocks of data, typically 128 bits (16 bytes), but supports key sizes of 128, 192, or 256 bits. AES encryption involves a series of mathematical transformations on blocks of data. Here's a step-by-step breakdown of the AES process and the math behind each operation. 1. State Representation AES operates on a 4x4 matrix of bytes (called the "state"). If the input data is 128 bits (16 bytes), it is split into 16-byte blocks that fit into this matrix. Let’s represent the input block (plaintext) as a 4x4 matrix: State = ( P 00 P 01 P 02 P 03 P 10 P 11 P 12 P 13 P 20 P 21 P 22 P 23 P 30 P 31 P 32 P 33 ) \text{State} = \begin{pmatrix} P_{00} & P_{01} & P_{02} & P_{03} \\ P_{10} & P_{11} & P_{12} & P_{13} \\ P_{20} & P_{21} & P_{22} & P_{23} \\ P_{30} & P_{31} & P_{32}

Physical Layer: Implement Encryption or Jamming-Resistant Modulation Technique

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PART-1 This segment will focus on implementing XOR encryption, a straightforward encryption technique. To bolster security, I'll also introduce frequency hopping, which involves altering the transmission frequency to avoid interference. Data Security at the Physical Layer: A Case Study At the physical layer of the communication model, the primary objective is to guarantee the confidentiality of transmitted data. This is typically achieved through encryption, a process that transforms plaintext into ciphertext, rendering it unintelligible to unauthorized parties. One common encryption method applied before modulation is XOR encryption. XOR Encryption: A Simple Yet Effective Technique XOR encryption involves the bitwise XOR operation between the plaintext and a key. The result is the ciphertext. The beauty of XOR lies in its reversibility; the same key can be used to decrypt the ciphertext back into the original plaintext. XOR encryption  is a simple yet effective encryption mechanis