Randomization in C with NFSR logic

NFSR (Non-Linear Feedback Shift Register) logic can be considered superior to the standard rand() function in C for certain use cases, particularly when generating cryptographically secure or high-quality random numbers. Additionally, this type of randomization is performed directly by the CPU, eliminating the need to generate random values in SystemVerilog (SV) and transfer them to memory for later use.Here are several reasons why NFSR might be preferred over the rand()function:

  1. Higher Quality Randomness:NFSR generates more uniformly distributed random numbers, minimizing patterns or cycles, which is crucial for applications that demand high-quality randomness.
  2. Cryptographic Security:NFSR is commonly used in cryptographic algorithms because its output is difficult to predict or reverse-engineer, making it ideal for secure applications. In contrast, the standard rand() function is not secure and can be easily predicted if an attacker knows the algorithm.
  3. Longer Period:NFSRs generally have longer periods before repeating their sequence, making them better suited for applications that require randomness over extended durations (like simulations). In contrast, rand() has a shorter period, which means its sequence can repeat more quickly.
  4. No Need for Reseeding:NFSR maintains randomness without frequent reseeding, whereas rand() requires proper reseeding , to avoid generating predictable patterns.
  5. Performance:NFSR logic can be more efficient, especially when optimized for parallelism or hardware, whereas rand() is generally slower and less suited for complex applications.

In summary, NFSR offers greater robustness, security, and high-quality randomness, making it ideal for cryptographic or simulation contexts, while rand() is simpler but unsuitable for high-security or high-quality randomness needs.

Additionally, a test seed number can be incorporated into the randomization process, allowing for seed-specific randomization in your C tests. Here is the code example demonstrating how to implement the NFSR function and use it:

Vtool_How_to_randomize_data_without_standard_rand()_function_and_with_high_quality_random_numbers.