Lesson plan
/dev/random
of In Unix-like operating systems, and are special files that provide random numbers from a cryptographically secure pseudorandom number generator (CSPRNG). The CSPRNG is seeded with entropy (a value that provides randomness) from environmental noise, collected from device drivers and other sources. Users can obtain random numbers from the CSPRNG simply by reading the file. Not all operating systems implement the same methods for and . When entropy available is low, will block; on newer systems, this typically happens at program startup until entropy is sufficient, before permanently unblocking. The device typically was never a blocking device, even if the pseudorandom number generator seed was not fully initialized with entropy since boot. This special file originated in Linux in 1994. It was quickly adopted by other Unix-like operating systems.
Article summary
of In Unix-like operating systems, and are special files that provide random numbers from a cryptographically secure pseudorandom number generator (CSPRNG). The CSPRNG is seeded with entropy (a value that provides randomness) from environmental noise, collected from device drivers and other sources. Users can obtain random numbers from the CSPRNG simply by reading the file. Not all operating systems implement the same methods for and . When entropy available is low, will block; on newer systems, this typically happens at program startup until entropy is sufficient, before permanently unblocking. The device typically was never a blocking device, even if the pseudorandom number generator seed was not fully initialized with entropy since boot. This special file originated in Linux in 1994. It was quickly adopted by other Unix-like operating systems.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.