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Cryptography/SSL 101 #2: Cryptographic hash functions
 
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This video builds on the first one and introduces hash functions as a way to create a "unique" finger print of any digital entity like a number, a word or a file - anything that can be represented as a number.
Views: 10442 Matt Thomas
21. Cryptography: Hash Functions
 
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MIT 6.046J Design and Analysis of Algorithms, Spring 2015 View the complete course: http://ocw.mit.edu/6-046JS15 Instructor: Srinivas Devadas In this lecture, Professor Devadas covers the basics of cryptography, including desirable properties of cryptographic functions, and their applications to security. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 76127 MIT OpenCourseWare
What are Cryptographic Hash Functions?
 
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In this video, I explain what cryptographic hash functions are. This is for programmers and non-programmers alike. Hash Functions are very important in computer science with applications everywhere. Follow me on twitter: https://twitter.com/tweetsByAnkush Read programming articles: https://medium.com/@ankushc Logo credits: Shreya Kundu https://www.instagram.com/shreyadoodles/ Intro Music Credits: PACIFIC SUN by Nicolai Heidlas Music https://soundcloud.com/nicolai-heidlas Creative Commons — Attribution 3.0 Unported— CC BY 3.0 http://creativecommons.org/licenses/b... Music promoted by Audio Library https://youtu.be/kbqmEJTr3nU Music by HookSounds [ http://www.hooksounds.com ]
Views: 426 Code Cap
Bitcoin - Cryptographic hash function
 
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What cryptographic hash functions are and what properties are desired of them. More free lessons at: http://www.khanacademy.org/video?v=0WiTaBI82Mc Video by Zulfikar Ramzan. Zulfikar Ramzan is a world-leading expert in computer security and cryptography and is currently the Chief Scientist at Sourcefire. He received his Ph.D. in computer science from MIT.
Views: 222914 Khan Academy
Cryptography 101
 
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Cryptography is a complex and confusing subject. In this talk you will learn about the core components of cryptography used in software development: securing data with encryption, ensuring data integrity with hashes and digital signatures, and protecting passwords with key derivation functions. While learning how to use these components, you will also learn the best practices that drive strong cryptography. This talk won’t make you a cryptography expert but it will give you the knowledge necessary to use cryptography properly. No prior knowledge of cryptography is required for this presentation. EVENT: the Dutch PHP Conference in 2018 SPEAKER: Adam Englander PERMISSIONS: Original video was published with the Creative Commons Attribution license (reuse allowed). CREDITS: Original video source: https://www.youtube.com/watch?v=KcjJ19geKmA&t=1s
Views: 7599 Coding Tech
One Way Function - Applied Cryptography
 
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This video is part of an online course, Applied Cryptography. Check out the course here: https://www.udacity.com/course/cs387.
Views: 12018 Udacity
Cryptography-101 [06] - HASH (in Bangla/Bengali)
 
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Cryptography-101 [06] - HASH (in Bangla/Bengali) === HASH Hash Functions Cryptographic Hash Function Use of Hash Hash Function Properties Requirements for Hash Function Secure Hash Algorithm (SHA) Comparison of SHA Parameters === Mohammad Mahmud kabir MahmudKabir.com
Views: 169 Mahmud Kabir
Applied Cryptography: Hash Functions - Part 1
 
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This video gives a general idea on what hash functions are and their uses. It also describes a use of hash functions for a digital signature protocol.
Views: 30753 Leandro Junes
Cryptographic Hash Functions - CompTIA Security+ SY0-301: 6.2
 
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See our entire index of CompTIA Security+ videos at http://www.FreeSecurityPlus.com - Cryptographic hashes provide us with features such as authentication, integrity, confidentiality, and non-repudiation. In this video, you'll learn about some of the most popular hashing ciphers.
Views: 20793 Professor Messer
Hash Function - CS101 - Udacity
 
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Other units in this course below: Unit 1: http://www.youtube.com/playlist?list=PLF6D042E98ED5C691 Unit 2: http://www.youtube.com/playlist?list=PL6A1005157875332F Unit 3: http://www.youtube.com/playlist?list=PL62AE4EA617CF97D7 Unit 4: http://www.youtube.com/playlist?list=PL886F98D98288A232 Unit 5: http://www.youtube.com/playlist?list=PLBA8DEB5640ECBBDD Unit 6: http://www.youtube.com/playlist?list=PL6B5C5EC17F3404D6 Unit 7: http://www.youtube.com/playlist?list=PL6511E7098EC577BE Q&A: http://www.youtube.com/playlist?list=PLDA5F9F71AFF4B69E To gain access to interactive quizzes, homework, programming assignments and a helpful community, join the class at http://www.udacity.com
Views: 34256 Udacity
Hashing: Why & How?
 
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Why do we wish to reduce a long list to a short one? How to do it, so that the short list will identify the long list. How to do it so that it is impossible to identify the long list from the short one, and the implications of the fact that many long lists share the very same short list. Hashing configurations: straight encryption, MD4, MD5, SHA-1, SHA-2.
Views: 145367 Gideon Samid
Hash Tables and Hash Functions
 
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This video describes the fundamental principles of the hash table data structure which allows for very fast insertion and retrieval of data. It covers commonly used hash algorithms for numeric and alphanumeric keys and summarises the objectives of a good hash function. Collision resolution is described, including open addressing techniques such as linear and quadratic probing, and closed addressing techniques such as chaining with a linked list.
Views: 251853 Computer Science
Lecture 20: Hash Functions by Christof Paar
 
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For slides, a problem set and more on learning cryptography, visit www.crypto-textbook.com
Encryption and Hashing explanation and differences in 5 minutes
 
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A very basic level and almost non technical explanation of the terms encryption and hashing
Views: 2154 Imran Hossain
Cryptographic Hash Functions
 
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Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in
Views: 12851 nptelhrd
cryptography - Hash Functions
 
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Cryptography To get certificate subscribe: https://www.coursera.org/learn/cryptography ======================== Playlist URL: https://www.youtube.com/playlist?list=PL2jykFOD1AWb07OLBdFI2QIHvPo3aTTeu ============================ Youtube channel: https://www.youtube.com/user/intrigano ============================ https://scsa.ge/en/online-courses/ https://www.facebook.com/cyberassociation/
Views: 961 intrigano
How Does SHA-1 Work - Intro to Cryptographic Hash Functions and SHA-1
 
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Learn more advanced front-end and full-stack development at: https://www.fullstackacademy.com SHA-1 stands for Secure Hash Algorithm 1, a cryptographic hash function developed by the NSA that can be used to verify that a file has been unaltered. In this video, we go over the basic features and common implementations of cryptographic hash functions before diving into the inner workings of a Javascript implementation of the SHA-1 function. Although out of use now, walking through the hash function code provides valuable insight into how these algorithms work. Watch this video to learn: - What are Cryptographic Hash Functions - Practical uses for Cryptographic Hash Functions - How does SHA-1 work
Views: 14219 Fullstack Academy
Lesson 14: One-way and hash functions (intypedia)
 
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Usually cryptographic algorithms are based on processes that are easy to calculate in one direction but difficult to invert without a trapdoor. Author: Dr. Hugo Krawczyk, IBM - USA. Script, slideshow and exercises: http://www.intypedia.com/?lang=en An intypedia team video.
Views: 7113 UPM
Hash Function
 
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Views: 2602 Internetwork Security
What is Hashing? Hash Functions Explained Simply
 
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What is hashing? In this video we explain how hash functions work in an easy to digest way. Hashing is the process of converting an input of any length into a fixed size string of text, using a mathematical function. 👩‍🎓👨‍🎓Learn blockchain fast at the Lisk Academy: https://lisk.io/academy Thanks for watching! Lisk makes it easy for developers to build and deploy blockchain applications in JavaScript. Learn about the leading platform for world-changing dapps at https://lisk.io/products. 👨‍💻👩‍💻 For developers: Documentation: https://lisk.io/documentation GitHub: https://github.com/LiskHQ Gitter: https://gitter.im/LiskHQ/lisk 🔒 Store your LSK in our official wallet: https://lisk.io/hub/ 🔎 View our blockchain explorer: https://explorer.lisk.io/ 🗞Read our latest news on the Lisk Blog: https://blog.lisk.io/ 👩‍🚀👨‍🚀 Meet the team: https://lisk.io/team 🎥 For media inquiries, please email us at press [at] lisk [dot] io. 👫Join our community channels: Reddit: http://reddit.com/r/lisk Twitter: http://twitter.com/liskhq Telegram: https://t.me/Lisk_HQ Lisk.chat: https://lisk.chat/ Instagram: http://instagram.com/liskhq Facebook: http://facebook.com/liskhq LinkedIn: https://www.linkedin.com/company/lisk/
Views: 40042 Lisk
Message Digest and Digital Signature | Cryptographic Hash Function
 
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This video lecture is produced by S. Saurabh. He is B.Tech from IIT and MS from USA. Message Digest and Digital Signature To study interview questions on Linked List watch http://www.youtube.com/playlist?list=PL3D11462114F778D7&feature=view_all To prepare for programming Interview Questions on Binary Trees http://www.youtube.com/playlist?list=PLC3855D81E15BC990&feature=view_all To study programming Interview questions on Stack, Queues, Arrays visit http://www.youtube.com/playlist?list=PL65BCEDD6788C3F27&feature=view_all To watch all Programming Interview Questions visit http://www.youtube.com/playlist?list=PLD629C50E1A85BF84&feature=view_all To learn about Pointers in C visit http://www.youtube.com/playlist?list=PLC68607ACFA43C084&feature=view_all To learn C programming from IITian S.Saurabh visit http://www.youtube.com/playlist?list=PL3C47C530C457BACD&feature=view_all
Views: 12878 saurabhschool
Blockchain 101 | Part 2: Cryptographic Hash Functions
 
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Cryptographic hash functions represent the basis of the blockchain technology. Here's a simple explanation of what they are and how they work, presented by Timotej Bodlaj (Portfolio Manager at Solidum Capital). Prefer to read this in greater detail? https://solidum.capital/blog/blockchain-101-part-2-fcd3-6880-add7-fb45-or-what-hell-are-hash-functions ••• SOLIDUM CAPITAL is a digital asset management company for the crypto community. Their world-class crypto portfolios provide simple access to the most perspective global crypto. The team consists of experienced professionals with over 15 years of experience in the traditional fund management industry, private equity, strategic consulting, and information technology. The team firmly believes in the long-term potential of blockchain technology, and their goal is to educate people about the potential of this technology and crypto investments as such. FOLLOW Solidum Capital crypto news, insights, and debates here: • Website: https://www.solidum.capital • Twitter: https://twitter.com/SolidumCapital • Facebook: https://www.facebook.com/SolidumCapital • Telegram: https://t.me/SolidumCapital • Medium: https://blog.solidum.capital • LinkedIn: https://www.linkedin.com/company/solidumcapital Subscribe to our WEEKLY NEWSLETTER and get recaps of crypto news, investment insights, ICO and coin analysis, and much more: https://bit.ly/2shZ01A. ••• Solidum Capital also manages the SOLIDUM PRIME CRYPTO FUND (SOPR Digital Portfolio) on the ICONOMI platform: https://my.iconomi.net/asset/SOPR ••• DISCLAIMER This video is for informational and discussion purposes only and does not constitute a marketing message, an investment survey, an investment recommendation, or investment advice. Please do your own research before making any investment decisions. Cryptocurrency investments are highly volatile and risky in nature. Don't invest more than what you can afford to lose. Solidum Capital makes no representations, warranties, or assurances as to the accuracy, currency or completeness of the content contained in this video or any sites linked to or from this video.
Views: 41 Solidum Capital
Bao, a general purpose cryptographic tree hash, and perhaps the fastest hash function in the world
 
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Project: https://github.com/oconnor663/bao Slides: https://jacko.io/bao_presentation/presentation.html Event URL: https://www.meetup.com/Rust-NYC/events/256499782 This is the talk I gave at the Rust NYC meetup on November 27, 2018. Speed demos are at 3m48s and 43m08s, and the encoding/decoding demo ("Barney the Demosaur") starts at 12m36s.
Views: 981 Jack O'Connor
The cryptographic hash function BLAKE
 
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The cryptographic hash function BLAKE Animation overview/visualization of how the hash function works Originally here: www.youtube.com/watch?v=PgpJNRnx6eY not sure why this was removed as its a great animation showing how the hash function works Full credits goes to the author(s) which are listed in the animation "BLAKE is one of the five hash functions in the final of the NIST SHA-3 Competition. BLAKE is one of the simplest designs to implement, and relies on previously analyzed components: the HAIFA structure and the ChaCha core function." https://131002.net/blake/ *Copyrights - Thought to be originally released as Public domain and used here in Fair Use
Views: 6927 Blue Dragon
Cryptographic Hash Function - Applied Cryptography
 
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This video is part of an online course, Applied Cryptography. Check out the course here: https://www.udacity.com/course/cs387.
Views: 9409 Udacity
Properties of Hash Functions (CSS441, L18, Y15)
 
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One-way property, weak collision resistant and strong collision resistant hash functions. Course material via: http://sandilands.info/sgordon/teaching
Views: 3151 Steven Gordon
CSE571-11-11: Cryptographic Hash Functions
 
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Audio/Video Recording of Professor Raj Jain's class lecture on Cryptographic Hash Functions. It covers Hash Function, Cryptographic Hash Functions, Applications of Crypto Hash Fn, Birthday Problem, Probability of Hash Collisions, Hash Function Cryptanalysis, Block Ciphers as Hash Functions, Secure Hash Algorithm (SHA), SHA-1 Algorithm, SHA-2, SHA-512 SHA-512 Round Function, 80-Word Input Sequence, SHA-3, SHA-3 Requirements
Views: 7743 Raj Jain
What is a crytographically secure hash function?
 
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Modern cryptography depends on the existence of several special kinds of mathematical functions. One important kind is a one-way function. One-way functions are easy to compute but very hard for anyone to invert. Sometimes we refer to these functions as hash functions and their output as a hash. Cryptographic hash functions are a subset of hash functions that have special properties important to their use in cryptography. Credits: Talking: Geoffrey Challen (Assistant Professor, Computer Science and Engineering, University at Buffalo). Producing: Greg Bunyea (Undergraduate, Computer Science and Engineering, University at Buffalo). Part of the https://www.internet-class.org online internet course. A blue Systems Research Group (https://blue.cse.buffalo.edu) production.
Views: 498 internet-class
Cryptography/SSL 101 #3: Digital signatures
 
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This video builds on the first two and unites the concepts of public/private key encryption and cryptographic hash functions to explain digital signatures - a key concept that underpins the security model web transactions and bitcoin among many other things
Views: 11137 Matt Thomas
Five* non-cryptographic hash functions enter. One hash function leaves.
 
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Adam Harvey https://linux.conf.au/schedule/30208/view_talk When you say “hash function” in a room full of developers, people tend to think of the classics: MD5, SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-OHGODPLEASESTOP, and the like — cryptographic hash functions intended for cryptographic uses. There’s another world out there, though: non-cryptographic hashes. Sometimes you just need to figure out if you’ve already seen a string or structure. Sometimes you need a basic checksum. Sometimes you need a hash that’s just fast and can fit into a 32 bit integer. I’ll run through the state of the art in the world of non-cryptographic hashing — what your best options are, how they compare in terms of CPU and memory usage, and how they work. Who takes it? Whose mixing function reigns supreme? Let’s find out. * I’m saying “five”, but realistically I’m going to cover as many modern options as I can fit into the time available. Let’s say “five plus or minus two” in reality.
Fundamental difference between Hashing and Encryption algorithms
 
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A hash function could be considered the same as baking a loaf of bread. You start out with inputs (flour, water, yeast, etc...) and after applying the hash function (mixing + baking), you end up with an output: a loaf of bread. Going the other way is extraordinarily difficult - you can't really separate the bread back into flour, water, yeast - some of that was lost during the baking process, and you can never tell exactly how much water or flour or yeast was used for a particular loaf, because that information was destroyed by the hashing function (aka the oven). Many different variants of inputs will theoretically produce identical loaves (e.g. 2 cups of water and 1 tsbp of yeast produce exactly the same loaf as 2.1 cups of water and 0.9tsbp of yeast), but given one of those loaves, you can't tell exactly what combo of inputs produced it. Encryption, on the other hand, could be viewed as a safe deposit box. Whatever you put in there comes back out, as long as you possess the key with which it was locked up in the first place. It's a symmetric operation. Given a key and some input, you get a certain output. Given that output, and the same key, you'll get back the original input. It's a 1:1 mapping.
Views: 15586 The Sharp Turtles
Hashing Algorithms and Security - Computerphile
 
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Audible free book: http://www.audible.com/computerphile Hashing Algorithms are used to ensure file authenticity, but how secure are they and why do they keep changing? Tom Scott hashes it out. More from Tom Scott: http://www.youtube.com/user/enyay and https://twitter.com/tomscott http://www.facebook.com/computerphile https://twitter.com/computer_phile This video was filmed and edited by Sean Riley. Pigeon Sound Effects courtesy of http://www.freesfx.co.uk/ Computerphile is a sister project to Brady Haran's Numberphile. See the full list of Brady's video projects at: http://bit.ly/bradychannels
Views: 787584 Computerphile
C/C++ Cryptography — Simple Hashing Algorithm | Simple Hash Function
 
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• Support me on Patreon: http://www.patreon.com/Zer0Mem0ry • Donate Bitcoin: 1JhSKGgRQmir8rRF4Sm5CP4fDDofKFAypd • Facebook: https://www.facebook.com/Zer0Mem0ry • Twitter: https://www.twitter.com/Zer0Mem0ry
Views: 10142 Zer0Mem0ry
Encryption vs Hashing
 
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Views: 1018 Techno Thinkers
Cryptographic Hash Functions: Part 1
 
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Cryptographic Hash Functions Applications of Crypto Hash Functions Birthday Problem Secure Hash Algorithm (SHA)
Views: 8979 Scholartica Channel
What is Hashing on the Blockchain?
 
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What is Hashing on the Blockchain? https://blockgeeks.com/guides/what-is-hashing/ Cryptographic hashing is a key feature in the security and efficiency of blockchains. If you've ever wondered how so much data can be stored securely on every node in the network, hashing is a big part of the answer! We'll cover all the basics you need to know in this video! For more blockchain guides, courses, and videos, visit us at blockgeeks.com! Cryptographic hash functions A cryptographic hash function is a special class of hash functions which has various properties making it ideal for cryptography. There are certain properties that a cryptographic hash function needs to have in order to be considered secure. Let’s run through them one by one. Property 1: Deterministic This means that no matter how many times you parse through a particular input through a hash function you will always get the same result. This is critical because if you get different hashes every single time it will be impossible to keep track of the input. Property 2: Quick Computation The hash function should be capable of returning the hash of an input quickly. If the process isn’t fast enough then the system simply won’t be efficient. Property 3: Pre-Image Resistance What pre-image resistance states is that given H(A) it is infeasible to determine A, where A is the input and H(A) is the output hash. Notice the use of the word “infeasible” instead of “impossible”. We already know that it is not impossible to determine the original input from its hash value. Let’s take an example. Suppose you are rolling a dice and the output is the hash of the number that comes up from the dice. How will you be able to determine what the original number was? It’s simple all that you have to do is to find out the hashes of all numbers from 1-6 and compare. Since hash functions are deterministic, the hash of a particular input will always be the same, so you can simply compare the hashes and find out the original input. But this only works when the given amount of data is very less. What happens when you have a huge amount of data? Suppose you are dealing with a 128-bit hash. The only method that you have to find the original input is by using the “brute-force method”. Brute-force method basically means that you have to pick up a random input, hash it and then compare the output with the target hash and repeat until you find a match.
Views: 7174 Blockgeeks
Cryptographic Hash Functions (Contd...1)
 
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Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in
Views: 7765 nptelhrd
Bitcoin tutorial Episode 5: Cryptography, hash function, digital signature
 
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In this video we will look at Hash Functions Symmetric, Asymmetric Encryption and Digital Signatures
Views: 798 On1 Productions
Cryptography For Beginners
 
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Cryptography is a complex and confusing subject. In this talk you will learn about the core components of cryptography used in software development: securing data with encryption, ensuring data integrity with hashes and digital signatures, and protecting passwords with key derivation functions. While learning how to use these components, you will also learn the best practices that drive strong cryptography. This talk won’t make you a cryptography expert but it will give you the knowledge necessary to use cryptography properly. No prior knowledge of cryptography is required for this presentation. EVENT: Dutch PHP Conference in 2018 SPEAKER: Adam Englander PERMISSIONS: Original video was published with the Creative Commons Attribution license (reuse allowed). CREDITS: Original video source: https://www.youtube.com/watch?v=KcjJ19geKmA
Views: 45732 Coding Tech
Pigeonhole Principle and Hash Functions (Statistics Examples 5)
 
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Applying the pigeonhole principle to (cryptographic) hash functions to determine how many inputs collide on a single hash value.
Views: 1402 Steven Gordon
VLSI Implementations of the Cryptographic Hash Functions MD6
 
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A public competition organized by the NIST recently started, with the aim of identifying a new standard for cryptographic hashing (SHA-3).Besides a high security level,candidate algorithms should show good performance on various platforms.While an average performance on high-end processors is generally not critical, implementability and flexibility in hardware is crucial, because the new standard will be implemented in a variety of lightweight devices.This project investigates VLSI architectures of the SHA-3 candidates MD6.The fastest circuit is the 16×parallel MD6 core,reaching 16.3 Gbps at a complexity of 69.8k gate equivalents (GE) on ASIC and 8.4 Gbps using 4465 Slices on FPGA. However,large memory requirements preclude the application of MD6 to resource-constrained systems.
Views: 470 VERILOG COURSE TEAM
What is Hashing & Digital Signature in The Blockchain?
 
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What is Hashing & Digital Signature in The Blockchain? https://blockgeeks.com/ Today, we're going to be talking about the word blockchain and breaking it down to understand what does it mean when someone says, "Blockchain." What is hashing? Hashing refers to the concept of taking an arbitrary amount of input data, applying some algorithm to it, and generating a fixed-size output data called the hash. The input can be any number of bits that could represent a single character, an MP3 file, an entire novel, a spreadsheet of your banking history, or even the entire Internet. The point is that the input can be infinitely big. The hashing algorithm [00:01:00] can be chosen depending on your needs and there are many publicly available hashing algorithms. The point is that the algorithm takes the infinite input of bits, applies some calculations to them, and outputs a finite number of bits. For example, 256 bits. What can this hash be used for? A common usage for hashes today is to fingerprint files, also known as check zones. This means that a hash is used to verify that a file has not been [00:01:30] tampered with or modified in any way not intended by the author. If WikiLeaks, for example, publishes a set of files along with their MD5 hashes, whoever downloads those files can verify that they are actually from WikiLeaks by calculating the MD5 hash of the downloaded files, and if the hash doesn't match what was published by WikiLeaks, then you know that the file has been modified in some way. How does the blockchain make use of hashes? [00:02:00] Hashes are used in blockchains to represent the current state of the world. The input is the entire state of the blockchain, meaning all the transactions that have taken place so far and the resulting output hash represents the current state of the blockchain. The hash is used to agree between all parties that the world state is one in the same, but how are these hashes actually calculated? The first hash is calculated for the first block [00:02:30] or the Genesis block using the transactions inside that block. The sequence of initial transactions is used to calculate a block hash for the Genesis block. For every new block that is generated afterwords, the previous block's hash is also used, as well as its own transactions, as input to determine its block hash. This is how a chain of blocks is formed, each new block hash pointing to the block hash that came before it. This system of hashing guarantees that no transaction in the history can be tampered with because if any single part of the transaction changes, so does the hash of the block to which it belongs, and any following blocks' hashes as a result. It would be fairly easy to catch any tampering as a result because you can just compare the hashes. This is cool because everyone on the blockchain only needs to agree on 256 bits to represent the potentially infinite state of the blockchain. The Ethereum blockchain is currently tens of gigabytes, but the current state of the blockchain, as of this recording, is this hexadecimal hash representing 256 bits. What about digital signatures? Digital signatures, like real signatures, are a way to prove that somebody is who they say they are, except that we use cryptography or math, which is more secure than handwritten signatures that can be [00:04:00] easily forged. A digital signature is a way to prove that a message originates from a specific person and no one else, like a hacker. Digital signatures are used today all over the Internet. Whenever you visit a website over ACTPS, you are using SSL, which uses digital signatures to establish trust between you and the server. This means that when you visit Facebook.com, your browser can check the digital signature that came with the web page to verify that it indeed originated from Facebook and not some hacker. In asymmetric encryption systems, users generate something called a key pair, which is a public key and a private key using some known algorithm. The public key and private key are associated with each other through some mathematical relationship. The public key is meant to be distributed publicly to serve as an address to receive messages from other users, like an IP address or home address. The private key is meant to be kept secret and is used to digitally sign messages sent to other users. The signature is included with the message so that the recipient can verify using the sender's public key. This way, the recipient can be sure that only the sender could have sent this message. Generating a key pair is analogous to creating an account on the blockchain, but without having to actually register anywhere. Pretty cool. Also, every transaction that is executed on the blockchain is digitally signed by the sender using their private key. This signature ensures that only the owner of the account can move money out of the account.
Views: 26897 Blockgeeks
SHA-1 Hash Function
 
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Views: 53055 Kiran Kuppa
Strong Collision Resistance - Applied Cryptography
 
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This video is part of an online course, Applied Cryptography. Check out the course here: https://www.udacity.com/course/cs387.
Views: 6585 Udacity