A rainbow table is a precomputed table for reversing cryptographic hash functions, usually for cracking password hashes. Tables are usually used in recovering the plaintext password, up to a certain length consisting of a limited set of characters. It is a practical example of a space/time trade-off, using more computer processing time at the cost of less storage when calculating a hash on every attempt, or less processing time and more storage when compared to a simple lookup table with one entry per hash. Use of a key derivation function that employ a salt makes this attack infeasible.
Rainbow tables are an application of an earlier, simpler algorithm by Martin Hellman.
Read more about Rainbow Table: Background, Precomputed Hash Chains, Rainbow Tables, Defense Against Rainbow Tables, Common Uses, See Also
Famous quotes containing the words rainbow and/or table:
“Once it chanced that I stood in the very abutment of a rainbow’s arch, which filled the lower stratum of the atmosphere, tinging the grass and leaves around, and dazzling me as if I looked through colored crystal. It was a lake of rainbow light, in which, for a short while, I lived like a dolphin. If it had lasted longer it might have tinged my employments and my life.”
—Henry David Thoreau (1817–1862)
“Thou preparest a table before me in the presence of mine enemies; thou anointest my head with oil; my cup runneth over.”
—Bible: Hebrew Psalms, 23:5.