16 & 32 & 64\
SAT Iterations & 14 & 18 & 25 & 32 & TO\
SAT Execution Time $_{(Seconds)}$ & 0.01& 0.015 & 2.35 & 79.18 & TO\
*TO: Timeout = $2\times10^6$ seconds*

**Algebraic Attacks**
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Algebraic attacks involve (a) expressing the cipher operations as a system of equations, (b) substituting in known data for some variables, and (c) solving for the key. ACORN has been demonstrated to be resistant against all known types of algebraic attacks, including linear cryptanalysis. Therefore, in the absence of any new attacks, the TRN transmission mode is resistant against algebraic attacks. Using CSTN and RCSTN by itself is new and requires more analysis. CSTN can be expressed as an affine function of the data input $x$, of the form $y=A\cdot x + b$, where $A$ is an $n \times n$ matrix and $b$ is an $n \times 1$ vector, with all elements dependent on the input TRN. Although recovering $A$ and $b$ is not equivalent to finding the TRN, it may enable the successful decryption of all blocks encrypted using a given TRN. We protect against this threat in numerous ways: (1) The number of blocks encrypted using a given TRN is 