random number generators

A random number generator is a computational or physical device designed to generate a sequence of numbers that does not have any easily discernable pattern, so that the sequence can be treated as being random. Random number generators have existed since ancient times, in the form of dice and coin flipping, the shuffling of playing cards, the use of yarrow stalks in the I Ching, and many other methods. Random number generator - True random numbers vs. pseudo-random numbers. Main article: pseudo-ran ...

Including:

• Random number generator - True random numbers vs. pseudo-random numbers
• Random number generator - Generating random numbers from physical processes
• Random number generator - Post-processing and statistical checks
• Random number generator - Uses of random numbers
• Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia - Random number generator

Random Number Generator, RNG:

 See Random Event Generator .

(See also: Random Number Generator, RNG, Psychic, Psychic Dictionary, Parapsychology, Parapsychology Dictionary)

See also:

Random number generator, Random number generator - True random numbers vs. pseudo-random numbers, Random number generator - Random numbers in computing, Random number generator - Generating random numbers from physical processes, Random number generator - Post-processing and statistical checks, Random number generator - Uses of random numbers, Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia II - Random number generator - Uses of random numbers

The word random is used to express apparent lack of purpose, cause, or order. The term randomness is often used synonymously with a number of measurable statistical properties, such as lack of bias or correlation. Randomness has an important place in science and philosophy. Randomness - History. Humankind has been concerned with randomness since prehistoric times, mostly through divination (reading messages in random patterns) and gambling. The opposition between free will ...

Including:

• Randomness - History
• Randomness - Randomness versus unpredictability
• Randomness - Misconceptions/logical fallacies
• Randomness - A number is due
• Randomness - A number is cursed
• Randomness - Study of randomness
• Randomness - In philosophy
• Randomness - In biology
• Randomness - In the natural sciences
• Randomness - Source of randomness
• Randomness - In mathematics
• Randomness - In communication theory
• Randomness - In finance
• Randomness - Applications and use of randomness
• Randomness - Generating randomness
• Randomness - Quotations
• Randomness - Books

Read more here: » Randomness: Encyclopedia - Randomness

There exist many functions that computers can ultilize that obey statistical laws of randomness, and usually provide a number between 0 and 1, to a certain number of decimal places, usually three. This means, that for N trials, the number of expected outcomes = N/(number of outcomes). It is often quoted that such functions are deterministic, and therefore not truly random, however, these people pre-suppose that the person determining the output has access to the microsecond value that was used by the rand ...

See also:

Random number generator, Random number generator - True random numbers vs. pseudo-random numbers, Random number generator - Random numbers in computing, Random number generator - Generating random numbers from physical processes, Random number generator - Post-processing and statistical checks, Random number generator - Uses of random numbers, Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia II - Random number generator - Random numbers in computing

"Unpredictable" random numbers were first investigated in the context of gambling, and many randomizing devices such as dice, shuffling playing cards, and roulette wheels, were first developed for use in gambling. Fairly produced random numbers are vital to electronic gambling and ways of creating them are sometimes regulated by governmental gaming commissions. "Random" numbers are also used for non-gambling purposes, both where their use is mathematically important, such as sampling for opinion polls, and in situations where "fairnes ...

See also:

Hardware random number generator, Hardware random number generator - Contrast with pseudo-random number generators, Hardware random number generator - Uses of random numbers, Hardware random number generator - Early attempts to generate true random numbers, Hardware random number generator - Physical phenomena used for random number generation, Hardware random number generator - Dealing with bias, Hardware random number generator - Attempts to clean up non-random bit-streams, Hardware random number generator - Estimating the size of the entropy pool, Hardware random number generator - Software implementation of random number generators from observed events, Hardware random number generator - Problems, Hardware random number generator - Checking the performance of hardware random number generators

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Uses of random numbers

Most computer "random number generators" are not hardware devices, but are software routines implementing algorithms. Often they are supplied with such system software as language compilers (eg, as one or more library routines) or operating systems (eg, as system calls). These are more properly called pseudo-random number generators, and cannot produce truly random outputs. Algorithmic information theory defines a sequence of bits as non-random if it can be produced by some computer program that is shorter than that sequence (Chaitin-Kolmogo ...

See also:

Hardware random number generator, Hardware random number generator - Pseudo-random generators, Hardware random number generator - Uses, Hardware random number generator - Early attempts, Hardware random number generator - Random physical phenomena, Hardware random number generator - Dealing with bias, Hardware random number generator - Software whitening, Hardware random number generator - Estimating entropy, Hardware random number generator - Using observed events, Hardware random number generator - Problems, Hardware random number generator - Verifying performance

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Pseudo-random generators

What constitutes a "true" random number is often difficult to decide, since the concept of randomness is itself somewhat difficult to define. What is universally agreed is that any "random number generator" based solely on deterministic computation cannot be regarded as a "true" random number generator, since its output is inherently predictable. John von Neumann once famously said "Anyone who uses software to produce random numbers is in a state of sin" (some sources say "arithmetic methods" instead of "software"). Howe ...

See also:

Random number generator, Random number generator - True random numbers vs. pseudo-random numbers, Random number generator - Random numbers in computing, Random number generator - Generating random numbers from physical processes, Random number generator - Post-processing and statistical checks, Random number generator - Uses of random numbers, Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia II - Random number generator - True random numbers vs. pseudo-random numbers

Many modern random number generators attempt to use some form of quantum-mechanical noise, widely considered to be the gold standard for randomness. (For a discussion of empirical verification of quantum unpredictability, see Bell test experiments). Some phenomena used include: A nuclear decay radiation source (as, for instance, from some kinds of commercial smoke-alarms), detected by a Geiger counter attached to a PC. Atmospheric noise, detected by a radio receiver attached to a PC Therma ...

See also:

Hardware random number generator, Hardware random number generator - Pseudo-random generators, Hardware random number generator - Uses, Hardware random number generator - Early attempts, Hardware random number generator - Random physical phenomena, Hardware random number generator - Dealing with bias, Hardware random number generator - Software whitening, Hardware random number generator - Estimating entropy, Hardware random number generator - Using observed events, Hardware random number generator - Problems, Hardware random number generator - Verifying performance

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Random physical phenomena

There is a general consensus that if there are such things as "true" random numbers, they are likely to be found by looking at physical processes which are, as far as we know, unpredictable. A physical random number generator is based on an essentially random atomic or subatomic physical phenomenon. Examples of such phenomena include radioactive decay, thermal noise, and shot noise. Physical random number generators relying on quantum mechanical processes have the advantage that the sequences they produce are completely unpredi ...

See also:

Random number generator, Random number generator - True random numbers vs. pseudo-random numbers, Random number generator - Random numbers in computing, Random number generator - Generating random numbers from physical processes, Random number generator - Post-processing and statistical checks, Random number generator - Uses of random numbers, Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia II - Random number generator - Generating random numbers from physical processes

Most computer "random number generators" are not hardware devices, but are software routines implementing algorithms. Often they are supplied with such system software as language compilers (eg, as one or more library routines) or operating systems (eg, as system calls). These are more properly called pseudo-random number generators, and cannot produce truly random outputs. Algorithmic information theory defines a sequence of bits as non-random if it can be produced by some computer program that is shorter than that sequence (Chaitin-Kolmogo ...

See also:

Hardware random number generator, Hardware random number generator - Contrast with pseudo-random number generators, Hardware random number generator - Uses of random numbers, Hardware random number generator - Early attempts to generate true random numbers, Hardware random number generator - Physical phenomena used for random number generation, Hardware random number generator - Dealing with bias, Hardware random number generator - Attempts to clean up non-random bit-streams, Hardware random number generator - Estimating the size of the entropy pool, Hardware random number generator - Software implementation of random number generators from observed events, Hardware random number generator - Problems, Hardware random number generator - Checking the performance of hardware random number generators

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Contrast with pseudo-random number generators

One early way of producing random numbers was by a variation of the same machines used to play keno or select lottery numbers. Basically, these mixed numbered ping-pong balls with blown air, and used some method to withdraw balls from the mixing chamber. This method gives reasonable results, but the random numbers generated by this means are expensive. The method is inherently slow, and is unusable in most mechanized situations. In 1927, Cambridge University Press published a book of Random sampling numbers, arranged by a stati ...

See also:

Hardware random number generator, Hardware random number generator - Contrast with pseudo-random number generators, Hardware random number generator - Uses of random numbers, Hardware random number generator - Early attempts to generate true random numbers, Hardware random number generator - Physical phenomena used for random number generation, Hardware random number generator - Dealing with bias, Hardware random number generator - Attempts to clean up non-random bit-streams, Hardware random number generator - Estimating the size of the entropy pool, Hardware random number generator - Software implementation of random number generators from observed events, Hardware random number generator - Problems, Hardware random number generator - Checking the performance of hardware random number generators

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Early attempts to generate true random numbers

Pseudo-random number generators (PRNGs) are algorithms that can automatically create long runs (for example, millions of numbers long) with good random properties but eventually the sequence repeats exactly (or the memory usage grows without bound). One of the most common PRNG is the linear congruential generator which uses the recurrence Xn + 1 = a ...

See also:

Random number generation, Random number generation - Physical methods, Random number generation - Computational methods

Read more here: » Random number generation: Encyclopedia II - Random number generation - Computational methods

Many modern random number generators attempt to use some form of quantum-mechanical noise, widely considered to be the gold standard for randomness. (For a discussion of empirical verification of quantum unpredictability, see Bell test experiments). Some phenomena used include: A nuclear decay radiation source (as, for instance, from some kinds of commercial smoke-alarms), detected by a Geiger counter attached to a PC. Atmospheric noise, detected by a radio receiver attached to a PC Therma ...

See also:

Hardware random number generator, Hardware random number generator - Contrast with pseudo-random number generators, Hardware random number generator - Uses of random numbers, Hardware random number generator - Early attempts to generate true random numbers, Hardware random number generator - Physical phenomena used for random number generation, Hardware random number generator - Dealing with bias, Hardware random number generator - Attempts to clean up non-random bit-streams, Hardware random number generator - Estimating the size of the entropy pool, Hardware random number generator - Software implementation of random number generators from observed events, Hardware random number generator - Problems, Hardware random number generator - Checking the performance of hardware random number generators

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Physical phenomena used for random number generation

The earliest methods for generating random numbers - dice, coin flipping, roulette wheels are still used today, mainly in games and gambling, as they tend to be too slow for applications in statistics and cryptography. Some physical phenomena, such as thermal noise in zener diodes appear to be truly random and can be used as the basis for hardware random number generators. However, many mechanical phenomena feature asymmetries and biases that make their outcomes not truly random. The many successful attempts to exploit such phenomena by gamblers, especia ...

See also:

Random number generation, Random number generation - Physical methods, Random number generation - Computational methods

Read more here: » Random number generation: Encyclopedia II - Random number generation - Physical methods

Subverted random numbers can be created using a cryptographically secure pseudo-random number generator with a seed value known to the attacker but concealed in the software. A relatively short, say 24 to 40 bit, portion of the seed can be truly random to prevent tell-tale repetitions, but not long enough to prevent the attacker from recovering, say, a "randomly" produced key. Random numbers typically go through several layers of hardware and software before they are used. Bits may be generated in a peripheral device, sent over a seri ...

See also:

Random number generator attack, Random number generator attack - Human generation of random quantities, Random number generator attack - Poorly designed random number generators, Random number generator attack - Attacks on software random number generators, Random number generator attack - Attacks on hardware random number generators, Random number generator attack - RNG subversion, Random number generator attack - Defenses

Read more here: » Random number generator attack: Encyclopedia II - Random number generator attack - RNG subversion

Even given sources of plausible random numbers, obtaining numbers which are completely unpredictable and unbiased is a very difficult task. Since random number generators are inherently designed to be unpredictable, it is difficult to ensure that they are being predictably unpredictable. For example, many hardware random number generators generate random numbers which tend to get focused in certain areas instead of being distributed uniformly, and their behavior may change with temperature, with voltage, with the age of the device, or ...

See also:

Random number generator, Random number generator - True random numbers vs. pseudo-random numbers, Random number generator - Random numbers in computing, Random number generator - Generating random numbers from physical processes, Random number generator - Post-processing and statistical checks, Random number generator - Uses of random numbers, Random number generator - Low-discrepancy sequences as an alternative

Read more here: » Random number generator: Encyclopedia II - Random number generator - Post-processing and statistical checks

Software engineers without true random number generators often try to develop them by measuring physical events available to the software. An exemplar is measuring the time between user key-strokes, and then taking the least significant bit (or two or three) of the count as a random digit. A similar approach has been applied by measuring task-scheduling, network hits, disk-head seek times and other internal events. The method is quite risky when it uses computer-controlled events because a clever, malicious programmer might be able to ...

See also:

Hardware random number generator, Hardware random number generator - Contrast with pseudo-random number generators, Hardware random number generator - Uses of random numbers, Hardware random number generator - Early attempts to generate true random numbers, Hardware random number generator - Physical phenomena used for random number generation, Hardware random number generator - Dealing with bias, Hardware random number generator - Attempts to clean up non-random bit-streams, Hardware random number generator - Estimating the size of the entropy pool, Hardware random number generator - Software implementation of random number generators from observed events, Hardware random number generator - Problems, Hardware random number generator - Checking the performance of hardware random number generators

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Software implementation of random number generators from observed events

"Unpredictable" random numbers were first investigated in the context of gambling, and many randomizing devices such as dice, shuffling playing cards, and roulette wheels, were first developed for use in gambling. Fairly produced random numbers are vital to electronic gambling and ways of creating them are sometimes regulated by governmental gaming commissions. "Random" numbers are also used for non-gambling purposes, both where their use is mathematically important, such as sampling for opinion polls, and in situations where "fairnes ...

See also:

Hardware random number generator, Hardware random number generator - Pseudo-random generators, Hardware random number generator - Uses, Hardware random number generator - Early attempts, Hardware random number generator - Random physical phenomena, Hardware random number generator - Dealing with bias, Hardware random number generator - Software whitening, Hardware random number generator - Estimating entropy, Hardware random number generator - Using observed events, Hardware random number generator - Problems, Hardware random number generator - Verifying performance

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Uses

One early way of producing random numbers was by a variation of the same machines used to play keno or select lottery numbers. Basically, these mixed numbered ping-pong balls with blown air, and used some method to withdraw balls from the mixing chamber. This method gives reasonable results, but the random numbers generated by this means are expensive. The method is inherently slow, and is unusable in most mechanized situations. In 1927, Cambridge University Press published a book of Random sampling numbers, arranged by a stati ...

See also:

Hardware random number generator, Hardware random number generator - Pseudo-random generators, Hardware random number generator - Uses, Hardware random number generator - Early attempts, Hardware random number generator - Random physical phenomena, Hardware random number generator - Dealing with bias, Hardware random number generator - Software whitening, Hardware random number generator - Estimating entropy, Hardware random number generator - Using observed events, Hardware random number generator - Problems, Hardware random number generator - Verifying performance

Read more here: » Hardware random number generator: Encyclopedia II - Hardware random number generator - Early attempts