What Is Hashing? A Guide With Examples.

Author Cory Hayashi

Posted Apr 13, 2023

Reads 4.1K

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Hashing is a term that has gained immense popularity in recent years, especially in the world of computing and cybersecurity. It refers to the process of converting data of any size into a fixed-size output using an algorithm. The generated output is known as a hash, and it serves as a unique digital fingerprint for the original data.

Hashing is an essential component of many modern technologies, including blockchain, encryption, and password storage. It offers numerous benefits such as ensuring data integrity, enhancing security, and facilitating faster data retrieval. However, despite its widespread use and importance, hashing remains a mystery to many people.

If you're looking to understand what hashing is all about and how it works, then you've come to the right place. In this guide, we'll explore everything you need to know about hashing - from its basics to practical examples that showcase its real-world applications. So buckle up and join us on this exciting journey!

Unraveling the Concept of Hashing: A Beginner's Guide

Are you curious about what hashing is and how it works? Simply put, hashing is a process that converts an original string of data into a shorter fixed-length code. This code is known as the hash value or simply hash. The main purpose of hashing is to speed up data indexing and retrieval in hash tables.

A hash table stores key-value pairs where each key is unique. The hash function generates a specific element (hash) for every unique key entered into the table. The table size determines the maximum number of keys that can be stored in it, and a good hash function ensures that each original key has a unique corresponding hash value. Furthermore, a good hash should be difficult to reverse using any mathematical hashing algorithm, thus ensuring the security of the original data.

One-way hashing algorithms are commonly used in digital signatures, cybersecurity, and password storage to convert passwords into hashes that cannot be easily converted back into their original keys. Understanding this concept can help you appreciate the importance of data protection and cybersecurity measures in today's world.--

What is hashing used for?

Hashing is a process used by developers to store and retrieve data quickly. It involves using a hashing function to transform representative integer values of map object data into fixed size hash codes that can be used as keys to identify the object data map. Hash tables support functions like insert key and delete key, enabling rapid data retrieval. Additionally, hashing helps encrypt and decrypt digital signatures, as well as authenticate message senders. A one-way hashing operation transforms an input message digest into a separate transmitted message digest, which is then used for indexing and enables access to the original data.

Untangling the World of Hashing

Hashing has become a valuable security mechanism in the tech industry, making data unreadable to anyone except those with the correct key. The process involves taking a piece of data and running it through a hashing algorithm that performs complex mathematical operations to generate a unique fixed-length string of characters, which acts as the hash value. This method is effective in preventing human eye preventing or malicious individuals from accessing sensitive information. Over the years, hashing algorithms have become more advanced, making it increasingly difficult for bad actors to reverse engineer hashed values without massive amounts of computing power.

Nonces make hashing even more secure by adding a random number to the input before it's hashed, creating a unique output every time even if the same input is used. This method prevents attackers from predicting the hash value and makes it even harder for them to crack it. At Built Ins expert contributor network publishes thoughtful solutions-oriented stories written by innovative tech professionals, and we understand that sharing compelling first-person accounts can help others learn about new technologies like hashing. As the tech industry's definitive destination, we aim to provide clear explanations of complex topics such as this so that everyone can stay informed about innovative security measures like hashing.

Understanding the Concept of Hashing in Data Structure

Hashing is a fundamental concept in computer science software engineering that involves the transformation of input strings into short alphanumeric hash keys. The underlying concept works by using a hash function to map the original data assets onto file space. This technique helps accelerate the process of accessing and storing data, making it easier for software engineers to retrieve information efficiently.

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In a scenario where hash codes generate shorter hashed keys, data map hashing helps narrow down where to store values and retrieve information quickly. To understand this better, imagine a library that uses the Dewey Decimal Classification system to organize its books. Each book has a unique number assigned to it based on its subject matter. In computer science, hashing works in a similar way but uses shorter hashed keys instead of long numbers. As such, this technique is essential in managing large amounts of data because it reduces search time and makes operations faster and more efficient.

1. What is hashing in cybersecurity?

Hashing is a method used in cybersecurity to protect sensitive information by converting it into a unique code or "hash" using encryption algorithms. This process enhances cybersecurity by making it difficult for hackers to breach and find data, even if they manage to obtain access. For example, if John Doe's social security number 273-76-1989 was hashed, the resulting code would be unrecognizable and unusable for any nefarious activities. Hashing helps secure passwords stored in databases by converting them into irreversible hashed strings that can only be decoded with a decryption key, thus preventing potential threat actors from accessing user accounts.

2. What is hashing in cryptography?

Hashing in cryptography is the process of using multiple hash functions to transform data into a secure message-digest hash function, such as MD2, MD4, SHA-1, SHA-2 or SHA-3. Popular cryptographic hashes include the secure hash algorithm 1 (SHA-1), secure hash algorithm 2 (SHA-2), and secure hash algorithm 3 (SHA-3). These algorithms are used to hash digital signatures and ensure that data is kept secure for database storage and retrieval purposes. The error-checking purposes of SHA-2 provides a larger 224-bit message digest while the newer standard algorithm of SHA-3 creates a larger 160-bit message digest hash function MD4 -- making it worth exploring further.

3. What is a collision?

In the world of cybersecurity, hashing is a crucial step in stopping threat actors. A hash function is an algorithm that takes data and creates a unique output, known as a hash. The goal is to ensure that even if someone gains access to the hashed data, they can't revert it back to its original state. However, sometimes identical hash values occur when open addressing handles collisions in a hash table. This contrast avoids collisions by having each hash table cell point to a linked list of values with identical hash function values. To further increase security, salting guarantees a unique output and obstructs bad actors from accessing non-unique passwords that users may reuse.

Unlocking the Secrets of Hashing Flexible Data Lengths

Hashing is a technique commonly used in computer science to convert data values of any size into fixed-size values. It's an ideal way of identifying items by assigning them a unique key. However, hashing flexible data lengths such as personal names web page addresses or natural language has always been a challenge due to complicated dependencies and highly non-uniform distributions. A hash function that uses character pairs characteristic can solve this problem and unlock the secret behind hashing flexible data lengths.

The Widespread Application of Hashing: What You Need to Know

Hashing is a process of converting any data into an encrypted format, primarily meant to ensure the message integrity, password validation and file integrity. The core function of hashing is to generate a unique value that represents the enclosed information, which can be used for identification purposes. Recently, blockchain technology has exposed hashing to a wider audience, as it is one of the key components of this distributed ledger system. In many cases, security relies on hashing to prevent interference with sensitive data. So whether you're using social media or banking online, understanding the basics of hashing is essential for protecting your information.

Hashing and Password Validation

With the rise of internet-led online activity, security researchers quickly realized that plaintext passwords wouldn't suffice for information privacy. In cases today, passwords are stored as a hashed value in the back-end database of a system. This step prevents anyone with access to the back-end server from seeing your password directly.

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Hash values are essentially an encrypted version of your password stored in the system. To provide additional security, systems store hashed values with a unique salt - a random 32-character string added to each password before hashing. Systems like Linux-based ones, for instance, add this unique salt to each password before hashing it.

If you've entered your password into a website or app that was affected by a data breach, it's crucial to know that simply changing your password isn't enough. If the system isn't validating whether you're using the same password that was previously stored in their database, hackers can easily use common household items to crack hash values and gain access to your account.

Unlocking the Secrets of Hashing for Non-Techies

Hashing is a method giving a unique code to any given input. In simpler terms, it's like generating a specific fingerprint for each piece of data. This process can be used for many things, including securing passwords or identifying duplicates in a database. There are common algorithms used in hashing such as the modulo division method or the more complex cryptographic hash functions. Understanding hashing integers and common methods can be helpful for non-techies who want to learn more about data security and efficiency.

1. Trivial hash function[edit]

A trivial hash function is a simple hash function that generates hash values for key values in a key space. These functions are essentially random and sufficiently uniformly distributed to ensure that the hash table has minimal collisions. For instance, a size 2 hash table can use a trivial hash function to map keys to indices 0 or 1. However, more complex data structures require more sophisticated hashing techniques.

2. Folding[edit]

Folding is a hashing technique that helps map large keys into smaller hash codes. It involves dividing the key into sections consisting of a fixed number of bits, then adding these sections together to obtain the final hash code. To ensure that the table size is not exceeded, excess bits are usually discarded at either the high or low end of the key. Parity-preserving bitwise operations such as 0x4def, 0x1357, 0x159e, and 0x091a can also be used to further reduce collisions. For example, by applying these operations and adding 0x8, we can obtain 0x7aa4 as our final hash code.

3. Mid-squares[edit]

The mid-squares method produces a hash code by squaring an arbitrary key, and taking the middle digits of the resulting 17-digit number ignoring leading and trailing zeros. For example, the key "391" produces 15241578750190521, and taking the middle 4 digits gives us a hash code of 5787. To ensure a reasonable hash code for a hash table size of 10000, we can use multiplicative hashing with a good multiplier such as the high digit (8750) from the mid-squares hash code.

4. Division hashing[edit]

Division hashing is a standard technique used in modern architectures including x86. It works by taking the modulo function of a key and a sufficiently random large prime number. However, it has a significant drawback when dealing with clustered keys or large key sets, where table size needs to be increased for good results. For example, if we have keys 123000, 456000 and 789000, by using modulo 1000 we would end up with only three slots in our hash table which is not sufficient. Therefore, choosing a prime number close to the table size is recommended for better performance.

5. Algebraic coding[edit]

Algebraic coding is a type of hashing that uses polynomial arithmetic modulo 2 to map keys to unique indices. By utilizing the division method and gf2 field Knuth, algebraic coding creates a hash function that produces fewer non-zero coefficients in the polynomial modulo 2. This results in a smaller set of nonzero coefficients, making it computationally feasible for microcode implementation while still achieving the usual outcome of a hash function – mapping keys to unique indices.

6. Unique permutation hashing[edit]

Unique permutation hashing is a method of creating a hash table that ensures no two keys will ever hash to the same value. This is achieved by generating unique permutations of the key and hashing each permutation separately. While this method can have a high worst-case insertion time, it results in a highly effective and secure hash table.

7. Fibonacci hashing[edit]

Fibonacci hashing, a type of multiplicative hashing, is used to uniformly distribute keys across table space blocks. This type of hashing uses consecutive keys to generate a hash value, with the high bits and low bits being multiplied by different Fibonacci numbers to ensure even distribution. The use of machine word length in this method helps to optimize memory usage and increase efficiency.

8. Zobrist hashing[edit]

Zobrist hashing, originally introduced by Albert Zobrist, an American computer scientist, is a technique used for constructing universal families of hash functions. It is particularly useful for compactly representing chess positions in computer game-playing programs. The idea behind the method involves combining table lookup with XOR operations using unique random numbers. This results in high-quality hash values for integer-number keys. By successively indexing 32-bit hashed integers, we can also use it for plain text integers. This technique has nice theoretical properties and is called 3-tuple independence meaning it uses three different sets of random numbers to generate hash values.

9. Customised hash function[edit]

Customised hash functions are often created to exploit existing entropy in data to produce more secure and efficient hash values. By varying the trailing zeros and volatile bits, a custom hash function can be created that produces uniform hash values that generally vary from input to input. Multiplicative schemes can also be used to create possibly faster hash functions selected divisors. Overall, customised hash functions provide a powerful tool for creating secure and uniform hash values.

How Hashing Ensures Message Integrity

Hashing is a process that helps ensure the integrity of messages, especially in situations where email relies on digital signatures to validate its authenticity. One-way hash function typically referred to as a hashing algorithm is used to generate a unique code, or hash, for each message. This code can then be used to verify whether the message has been tampered with or altered in transit.

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When senders digitally sign messages using their private key, they provide message integrity and authentication by using a one-way hashing function. The hashing algorithm generates an initial hash of the original message, which is then encrypted using the senders' private key. When the recipient receives the message, they use the sender's public key to decrypt the hash and compare it with a new hash generated from the received message. If both hashes match, it means that the message hasn't been tampered with during transmission, and its authenticity can be trusted. However, if there's any discrepancy between these hashes, it's evident that someone has modified or altered the message in transit, and we can no longer trust its validity.

Frequently Asked Questions

What is hashing in SQL Server?

Hashing in SQL Server is a process of converting a large data set into a smaller fixed-length value that represents the original data. This is helpful for faster searching and indexing of data.

What makes a good hash?

A good hash should have a unique combination of characters that cannot be easily reversed or duplicated, making it secure and tamper-proof. Additionally, a strong hashing algorithm should be used to prevent collisions and ensure the integrity of the data being hashed.

What are hash codes used for?

Hash codes are used to uniquely identify data and ensure its integrity. They are often used in security protocols, such as password storage, and in data retrieval systems for faster access.

What are hashing functions and how do they work?

Hashing functions are algorithms that convert input data of any size into a fixed-size output, called a hash or message digest. They work by applying mathematical operations to the input data, resulting in a unique and deterministic output value. These functions are commonly used for password storage, digital signatures, and data integrity verification.

Cory Hayashi

Cory Hayashi

Writer at Go2Share

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Cory Hayashi is a writer with a passion for technology and innovation. He started his career as a software developer and quickly became interested in the intersection of tech and society. His writing explores how emerging technologies impact our lives, from the way we work to the way we communicate.

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