COMPUTER FUNDAMENTALS

Detailed explanation-1: -In theoretical computer science and cryptography, a trapdoor function is a function that is easy to compute in one direction, yet difficult to compute in the opposite direction (finding its inverse) without special information, called the “trapdoor".

Detailed explanation-2: -In cryptography, a trapdoor is a secret backdoor hidden within an algorithm or individual piece of data. The idea is that people can’t find the backdoor without knowing about it in advance. It makes trapdoors extremely useful in cryptography, which keeps information secure by converting it into unbreakable codes.

Detailed explanation-3: -As of 2004, the best known trapdoor function (family) candidates are the RSA and Rabin families of functions. Both are written as exponentiation modulo a composite number, and both are related to the problem of prime factorization.

Detailed explanation-4: -In asymmetric cryptography, the trapdoor one-way function formula used for message encryption becomes the public key, and the secret information (trapdoor) used to compute its inverse becomes the private key.

Detailed explanation-5: -Trapdoor functions are a special kind of one-way function, where it is possible to calculate the reverse function with the knowledge of some secret value, which is called the trapdoor. If a trapdoor function is also a permutation (bijective, from a set to itself), then it’s called a trapdoor permutation.