ISAAC Random Number Generator

This node generates cryptographically secure random numbers using the ISAAC algorithm.

The ISAAC Random Number Generator provides high-quality pseudorandom numbers with optional seed and nonce control.

The ISAAC Random Number Generator node implements the ISAAC (Indirection, Shift, Accumulate, Add, and Count) algorithm by Robert J. Jenkins Jr. This cryptographically secure pseudorandom number generator produces uniformly distributed, unbiased output with extremely long periods and no short cycles.

Inputs

Configuration

Data	Description
Seed	Optional seed value for deterministic output (default: auto-generated)
Nonce	Optional nonce for additional randomization (default: none)

Actions

Signal	Description
Do	Generates a new random number

Outputs

Data	Description
Generated Value	The random number (0 to 1 trillion range)

Signal	Description
Done	Triggered when generation is complete

Algorithm Properties

The ISAAC algorithm provides exceptional randomness characteristics:

• Performance: 18.75 instructions per 32-bit value
• Period: Expected cycle length of 2^8295 values
• Security: No cycles shorter than 2^40 values
• Quality: Uniformly distributed, unbiased output
• Deterministic: Same seed produces same sequence

Usage

Basic Random Generation

• Leave both seed and nonce empty for true randomness
• Each execution produces a different random number
• Values range from 0 to 1,000,000,000,000

Deterministic Generation

• Set a specific seed for reproducible sequences
• Same seed always produces the same first random number
• Useful for testing, debugging, or procedural generation

Enhanced Randomization

• Use both seed and nonce for maximum control
• Nonce adds additional entropy while maintaining determinism
• Ideal for cryptographic applications requiring both security and reproducibility

Example Use Cases

1. Game Development:

   • Procedural world generation with consistent seeds
   • Random enemy behavior with controlled variance
   • Loot drops and reward systems

2. Simulations:

   • Monte Carlo simulations requiring high-quality randomness
   • Scientific modeling with reproducible results
   • A/B testing with controlled random assignments

3. Security Applications:

   • Session token generation
   • Random challenge generation
   • Cryptographic salt creation

4. Creative Applications:

   • Procedural art generation
   • Music composition algorithms
   • Animation parameter randomization

Seed and Nonce Behavior

Seed	Nonce	Behavior
Empty	Empty	Uses current time + Math.random() for entropy
Set	Empty	Deterministic sequence based on seed
Empty	Set	Random seed + nonce modification
Set	Set	Deterministic seed + nonce modification

Performance Characteristics

• Memory: ~2KB internal state per generator instance
• Speed: Extremely fast generation (millions of numbers per second)
• Quality: Passes all standard randomness tests
• Predictability: Cryptographically secure when properly seeded

Mathematical Foundation

ISAAC uses a combination of:

• Indirection: Memory array lookups
• Shift operations: Bit-level transformations
• Accumulation: State accumulation across generations
• Addition: Modular arithmetic
• Counting: Cycle counting for period extension

This combination ensures that the generator has excellent statistical properties and is suitable for both scientific and security applications.