"해시 함수"의 두 판 사이의 차이

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2020년 12월 16일 (수) 18:49 판

관련된 항목들

노트

  • The output of a hash function is often named a digest or a hash.[1]
  • We used SHA-256 (a hash function) to transform the input (the file) into a unique identifier (the digest).[1]
  • We can verify the authenticity of our file thanks to a security property of the hash function called second pre-image resistance.[1]
  • In this sense, the hash function alone doesn’t provide integrity.[1]
  • Perfect Hashing Colliding Keys A perfect hash function for the four names shown A hash function that maps names to integers from 0 to 15..[2]
  • Hash Function is a cryptographic function that takes a variable length of input and produces a fixed length output.[3]
  • With the hash function, it is impossible to generate the same hashed output from the different input text.[3]
  • As described earlier, the hash function generates a fixed length of output regardless of the length of the input you provide.[3]
  • Different blockchain uses different hash functions, bitcoin blockchain, for example, uses SHA-256 hash function to secure the data.[3]
  • The hash function maps the elements of the dataset via a key and generates hash values.[4]
  • The application possibilities of hash functions and associated concepts are extremely diverse.[4]
  • In encryption, hash functions also have special properties that make it impossible to reconstruct the data without having a key.[4]
  • If an entry is made into a database, it will be assigned a key by the hash function.[4]
  • There's no need to "reverse engineer" the hash function by analyzing the hashed values.[5]
  • In fact, the ideal hash function can't be derived by such analysis.[5]
  • A good hash function also should not produce the same hash value from two different inputs.[5]
  • There are several well-known hash functions used in cryptography.[5]
  • The enabled specializations of the hash template defines a function object that implements a hash function.[6]
  • Notably, some implementations use trivial (identity) hash functions which map an integer to itself.[6]
  • MD5 - An MD5 hash function encodes a string of information and encodes it into a 128-bit fingerprint.[7]
  • Clearly, a bad hash function can destroy our attempts at a constant running time.[8]
  • We want our hash function to use all of the information in the key.[8]
  • As we've described it, the hash function is a single function that maps from the key type to a bucket index.[8]
  • In practice, the hash function is the composition of two functions, one provided by the client and one by the implementer.[8]
  • There is no need to "reverse engineer" the hash function by analyzing the hashed values.[9]
  • The hash Function uses all the input data.[9]
  • The hash function "uniformly" distributes the data across the entire set of possible hash values.[9]
  • The hash function generates complicated hash values for similar strings.[9]
  • Definition - What does Hash Function mean?[10]
  • As mentioned briefly in the previous section, there are multiple ways for constructing a hash function.[11]
  • Every hash function must do that, including the bad ones.[11]
  • The hash function uses all the input data.[11]
  • There’s a real problem with our over-simplified hash function above.[12]
  • It is a hash function, yes, but it’s not a cryptographic hash function.[12]
  • Unfortunately, even when systems use cryptographically strong hash functions, there are ways for hackers to penetrate defenses.[12]
  • Many algorithms and schemes that provide a security service use a hash function as a component of the algorithm.[13]
  • Common names for the output of a hash function include also hash value, hash, and digital fingerprint.[13]
  • FIPS 198 specifies the computation of a MAC using an approved hash function.[13]
  • Hash functions can be used to determine if two objects are equal (possibly with a fixed average number of mistakes).[14]
  • The above example illustrates that the hash function can give the same results for different keys.[14]
  • The average seek time for locating a name in this table depends on the kind of data, , and the quality of the hash functions used.[14]
  • However, for reasonable choices of hash functions, it will be much smaller than .[14]
  • Rumor has it that you may have to run a second hash function on the output to make it random enough.[15]
  • The hash value is the result calculated by the hash function and algorithm.[16]
  • This property can be used to break naive authentication schemes based on hash functions.[17]
  • The output of a password hash function can also be used as a cryptographic key.[17]
  • One of the main applications of a hash function is to allow the fast look-up of data in a hash table.[17]
  • However, compared with standard hash functions, cryptographic hash functions tend to be much more expensive computationally.[17]
  • In fact, aside from their use in digital signatures, these hash functions are also used in other places in the bitcoin protocol as well.[18]
  • And by hash function, I basically mean that it will take input.[18]
  • A hash function that maps names to integers from 0 to 15.[19]
  • A hash function is any function that can be used to map data of arbitrary size to fixed-size values.[19]
  • The values returned by a hash function are called hash values, hash codes, digests, or simply hashes.[19]
  • Hash functions rely on generating favorable probability distributions for their effectiveness, reducing access time to nearly constant.[19]
  • Snowflake also provides hash functions, which take input value(s) and return a signed 64-bit numeric value.[20]
  • Snowflake provides both a scalar hash function and an aggregate hash function, both of which are listed here.[20]
  • Hash functions are by definition and implementation generally regarded as Pseudo Random Number Generators (PRNG).[21]
  • In general there is a theoretical hash function known as the Perfect Hash Function for any specific group of data.[21]
  • This is the measure of how well the hash function distributes the hash values of elements within a set of data.[21]
  • Each message is hashed using two different hash functions H 1 and H 2 .[21]
  • A hash function is a function that deterministically maps an arbitrarily large input space into a fixed output space.[22]
  • That's a pretty abstract description, so instead I like to imagine a hash function as a fingerprinting machine.[22]
  • The input to a hash function is usually called the preimage, while the output is often called a digest, or sometimes just a "hash.[22]
  • This means that given the same preimage (input), a hash function always produces the same digest.[22]
  • A hash function is a mathematical function that converts an input value into a compressed numerical value – a hash or hash value.[23]
  • As we discussed, a hash function lies at the heart of a hashing algorithm.[23]
  • This is because a hash function takes in data at a fixed-length.[23]
  • So, if the message is exactly of 512-bit length, the hash function runs only once (80 rounds in case of SHA-1).[23]
  • A hash function is a mathematical function that converts a numerical input value into another compressed numerical value.[24]
  • Values returned by a hash function are called message digest or simply hash values.[24]
  • In general, the hash is much smaller than the input data, hence hash functions are sometimes called compression functions .[24]
  • Hash function with n bit output is referred to as an n-bit hash function .[24]
  • The first step is to compute a hash function that transforms the search key into an array index.[25]
  • One possible approach to implementing a hash function is to use three digits from the key.[25]
  • For example, the code below computes a modular hash function for a String s, where R is a small prime integer (Java uses 31).[25]
  • We seek a hash function that is both easy to compute and uniformly distributes the keys.[25]
  • For example: For phone numbers, a bad hash function is to take the first three digits.[26]
  • In practice, we can often employ heuristic techniques to create a hash function that performs well.[26]
  • Thus, a hash function that simply extracts a portion of a key is not suitable.[26]
  • Hence it can be seen that by this hash function, many keys can have the same hash.[26]
  • In hashing, large keys are converted into small keys by using hash functions.[27]
  • An element is converted into an integer by using a hash function.[27]
  • Irrespective of how good a hash function is, collisions are bound to occur.[27]
  • Let us understand the need for a good hash function.[27]

소스

  1. ↑ 1.0 1.1 1.2 1.3 Hash functions and security
  2. ↑ Fundamentals of data structures: Hashing
  3. ↑ 3.0 3.1 3.2 3.3 What Is Hash Function
  4. ↑ 4.0 4.1 4.2 4.3 The Digital Marketing Wiki
  5. ↑ 5.0 5.1 5.2 5.3 Definition from WhatIs.com
  6. ↑ 6.0 6.1 cppreference.com
  7. ↑ What is Hashing? Benefits, types and more
  8. ↑ 8.0 8.1 8.2 8.3 Lecture 21: Hash functions
  9. ↑ 9.0 9.1 9.2 9.3 DAA Hash Function
  10. ↑ Definition from Techopedia
  11. ↑ 11.0 11.1 11.2 Hash Tables: Hash Functions
  12. ↑ 12.0 12.1 12.2 The Definitive Guide to Cryptographic Hash Functions (Part 1)
  13. ↑ 13.0 13.1 13.2 What Is the Hashing Function and Can It Become Vulnerable?
  14. ↑ 14.0 14.1 14.2 14.3 Hash Function -- from Wolfram MathWorld
  15. ↑ Hash Functions
  16. ↑ What is a hash function? Definition, usage, and examples
  17. ↑ 17.0 17.1 17.2 17.3 Cryptographic hash function
  18. ↑ 18.0 18.1 Bitcoin: Cryptographic hash functions (video)
  19. ↑ 19.0 19.1 19.2 19.3 Hash function
  20. ↑ 20.0 20.1 Utility & Hash Functions — Snowflake Documentation
  21. ↑ 21.0 21.1 21.2 21.3 .:: General Purpose Hash Function Algorithms
  22. ↑ 22.0 22.1 22.2 22.3 Hash Functions
  23. ↑ 23.0 23.1 23.2 23.3 Decoded: Examples of How Hashing Algorithms Work
  24. ↑ 24.0 24.1 24.2 24.3 Cryptography Hash functions
  25. ↑ 25.0 25.1 25.2 25.3 Hash Tables
  26. ↑ 26.0 26.1 26.2 26.3 What are Hash Functions and How to choose a good Hash Function?
  27. ↑ 27.0 27.1 27.2 27.3 Basics of Hash Tables Tutorials & Notes
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