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Top 10 Cryptography Algorithms in 2018
 
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In this video, I listed out Top 10 Cryptography Algorithms 10. MD5 9. SHA-0 8. SHA-1 7. HMAC 6. AES 5. Blowfish 4. DES 3. International Data Encryption Algorithm 2. Twofish 1. RSA Website: http://www.allabouttesting.org Please share and subscribe this video Disclaimer: This video is for educational purpose only. Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use.
Views: 2854 All About Testing
Asymmetric encryption - Simply explained
 
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How does public-key cryptography work? What is a private key and a public key? Why is asymmetric encryption different from symmetric encryption? I'll explain all of these in plain English! 🐦 Follow me on Twitter: https://twitter.com/savjee ✏️ Check out my blog: https://www.savjee.be 👍🏻 Like my Facebook page: https://www.facebook.com/savjee
Comparison of Encryption Algorithms
 
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This video is part of the Udacity course "Intro to Information Security". Watch the full course at https://www.udacity.com/course/ud459
Views: 1003 Udacity
Symmetric Key and Public Key Encryption
 
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Modern day encryption is performed in two different ways. Check out http://YouTube.com/ITFreeTraining or http://itfreetraining.com for more of our always free training videos. Using the same key or using a pair of keys called the public and private keys. This video looks at how these systems work and how they can be used together to perform encryption. Download the PDF handout http://itfreetraining.com/Handouts/Ce... Encryption Types Encryption is the process of scrambling data so it cannot be read without a decryption key. Encryption prevents data being read by a 3rd party if it is intercepted by a 3rd party. The two encryption methods that are used today are symmetric and public key encryption. Symmetric Key Symmetric key encryption uses the same key to encrypt data as decrypt data. This is generally quite fast when compared with public key encryption. In order to protect the data, the key needs to be secured. If a 3rd party was able to gain access to the key, they could decrypt any data that was encrypt with that data. For this reason, a secure channel is required to transfer the key if you need to transfer data between two points. For example, if you encrypted data on a CD and mail it to another party, the key must also be transferred to the second party so that they can decrypt the data. This is often done using e-mail or the telephone. In a lot of cases, sending the data using one method and the key using another method is enough to protect the data as an attacker would need to get both in order to decrypt the data. Public Key Encryption This method of encryption uses two keys. One key is used to encrypt data and the other key is used to decrypt data. The advantage of this is that the public key can be downloaded by anyone. Anyone with the public key can encrypt data that can only be decrypted using a private key. This means the public key does not need to be secured. The private key does need to be keep in a safe place. The advantage of using such a system is the private key is not required by the other party to perform encryption. Since the private key does not need to be transferred to the second party there is no risk of the private key being intercepted by a 3rd party. Public Key encryption is slower when compared with symmetric key so it is not always suitable for every application. The math used is complex but to put it simply it uses the modulus or remainder operator. For example, if you wanted to solve X mod 5 = 2, the possible solutions would be 2, 7, 12 and so on. The private key provides additional information which allows the problem to be solved easily. The math is more complex and uses much larger numbers than this but basically public and private key encryption rely on the modulus operator to work. Combing The Two There are two reasons you want to combine the two. The first is that often communication will be broken into two steps. Key exchange and data exchange. For key exchange, to protect the key used in data exchange it is often encrypted using public key encryption. Although slower than symmetric key encryption, this method ensures the key cannot accessed by a 3rd party while being transferred. Since the key has been transferred using a secure channel, a symmetric key can be used for data exchange. In some cases, data exchange may be done using public key encryption. If this is the case, often the data exchange will be done using a small key size to reduce the processing time. The second reason that both may be used is when a symmetric key is used and the key needs to be provided to multiple users. For example, if you are using encryption file system (EFS) this allows multiple users to access the same file, which includes recovery users. In order to make this possible, multiple copies of the same key are stored in the file and protected from being read by encrypting it with the public key of each user that requires access. References "Public-key cryptography" http://en.wikipedia.org/wiki/Public-k... "Encryption" http://en.wikipedia.org/wiki/Encryption
Views: 439647 itfreetraining
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: 65542 MIT OpenCourseWare
0406 AES, DES, 3DES
 
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Views: 10595 sonu123kashni
Cryptographic Algorithms
 
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Read more about this and watch video on my science popularization site: http://scienceup.org/computer-science/cryptographic-algorithms/
Views: 286 crnazvijezda
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: 989 Imran Hossain
Differences Between Encryption, Encoding and Hashing
 
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Differences Between Encryption, Encoding and Hashing
Views: 5183 LearnEveryone
What is CRYPTOGRAPHIC NONCE? What does CRYPTOGRAPHIC NONCE mean? CRYPTOGRAPHIC NONCE meaning
 
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What is CRYPTOGRAPHIC NONCE? What does CRYPTOGRAPHIC NONCE mean? CRYPTOGRAPHIC NONCE meaning - CRYPTOGRAPHIC NONCE definition - CRYPTOGRAPHIC NONCE explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ In cryptography, a nonce is an arbitrary number that may only be used once. It is similar in spirit to a nonce word, hence the name. It is often a random or pseudo-random number issued in an authentication protocol to ensure that old communications cannot be reused in replay attacks. They can also be useful as initialization vectors and in cryptographic hash function. A nonce is an arbitrary number used only once in a cryptographic communication, in the spirit of a nonce word. They are often random or pseudo-random numbers. Many nonces also include a timestamp to ensure exact timeliness, though this requires clock synchronization between organizations. The addition of a client nonce ("cnonce") helps to improve the security in some ways as implemented in digest access authentication. To ensure that a nonce is used only once, it should be time-variant (including a suitably fine-grained timestamp in its value), or generated with enough random bits to ensure a probabilistically insignificant chance of repeating a previously generated value. Some authors define pseudo-randomness (or unpredictability) as a requirement for a nonce. Authentication protocols may use nonces to ensure that old communications cannot be reused in replay attacks. For instance, nonces are used in HTTP digest access authentication to calculate an MD5 digest of the password. The nonces are different each time the 401 authentication challenge response code is presented, thus making replay attacks virtually impossible. The scenario of ordering products over the Internet can provide an example of the usefulness of nonces in replay attacks. An attacker could take the encrypted information and—without needing to decrypt—could continue to send a particular order to the supplier, thereby ordering products over and over again under the same name and purchase information. The nonce is used to give 'originality' to a given message so that if the company receives any other orders from the same person with the same nonce, it will discard those as invalid orders. A nonce may be used to ensure security for a stream cipher. Where the same key is used for more than one message and then a different nonce is used to ensure that the keystream is different for different messages encrypted with that key; often the message number is used. Secret nonce values are used by the Lamport signature scheme as a signer-side secret which can be selectively revealed for comparison to public hashes for signature creation and verification. Initialization vectors may be referred to as nonces, as they are typically random or pseudo-random. Nonces are used in proof-of-work systems to vary the input to a cryptographic hash function so as to obtain a hash for a certain input that fulfills certain arbitrary conditions. In doing so, it becomes far more difficult to create a "desirable" hash than to verify it, shifting the burden of work onto one side of a transaction or system. For example, proof of work, using hash functions, was considered as a means to combat email spam by forcing email senders to find a hash value for the email (which included a timestamp to prevent pre-computation of useful hashes for later use) that had an arbitrary number of leading zeroes, by hashing the same input with a large number of nonce values until a "desirable" hash was obtained. Similarly, the bitcoin block-chain hashing algorithm can be tuned to an arbitrary difficulty by changing the required minimum/maximum value of the hash so that the number of bitcoins awarded for new blocks does not increase linearly with increased network computation power as new users join. This is likewise achieved by forcing bitcoin miners to add nonce values to the value being hashed to change the hash algorithm output. Because cryptographic hash algorithms cannot easily be predicted based on their inputs, this makes the act of blockchain hashing and the possibility of being awarded bitcoins something of a lottery, where the first "miner" to find a nonce that delivers a desirable hash is awarded valuable bitcoins.
Views: 5076 The Audiopedia
How secure is 256 bit security?
 
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Supplement to the cryptocurrency video: How hard is it to find a 256-bit hash just by guessing and checking? What kind of computer would that take? Cryptocurrency video: https://youtu.be/bBC-nXj3Ng4 Thread for Q&A questions: http://3b1b.co/questions Several people have commented about how 2^256 would be the maximum number of attempts, not the average. This depends on the thing being attempted. If it's guessing a private key, you are correct, but for something like guessing which input to a hash function gives a desired output (as in bitcoin mining, for example), which is the kind of thing I had in mind here, 2^256 would indeed be the average number of attempts needed, at least for a true cryptographic hash function. Think of rolling a die until you get a 6, how many rolls do you need to make, on average? Music by Vince Rubinetti: https://vincerubinetti.bandcamp.com/album/the-music-of-3blue1brown ------------------ 3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe, and click the bell to receive notifications (if you're into that). If you are new to this channel and want to see more, a good place to start is this playlist: http://3b1b.co/recommended Various social media stuffs: Website: https://www.3blue1brown.com Twitter: https://twitter.com/3Blue1Brown Patreon: https://patreon.com/3blue1brown Facebook: https://www.facebook.com/3blue1brown Reddit: https://www.reddit.com/r/3Blue1Brown
Views: 835820 3Blue1Brown
Encryption: ECB v CBC
 
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http://asecuritysite.com/subjects/chapter58 I forgot to add the key to each of the stages of CBC.
Views: 15006 Bill Buchanan OBE
Types of Cryptography
 
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This video is part of the Udacity course "Intro to Information Security". Watch the full course at https://www.udacity.com/course/ud459
Views: 3582 Udacity
The Twofish Encryption Algorithm
 
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Twofish is a block cipher by Counterpane Labs, published in 1998. It was one of the five Advanced Encryption Standard (AES) finalists, and was not selected as AES. Twofish has a 128-bit block size, a key size ranging from 128 to 256 bits, and is optimized for 32-bit CPUs. Currently there is no successful cryptanalysis of Twofish. https://www.schneier.com/academic/twofish/ This animation is designed by Abdullah AlQahtani [email protected]
Views: 9308 Hemaya Group
symmetric key cryptography
 
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https://8gwifi.org/CipherFunctions.jsp Reference book: http://leanpub.com/crypto Cryptographic Algorithms generally fall into one of two different categories, or are a combination of both. Symmetric Fast Only provide confidentiality Examples: DES, AES, Blowfish, RC4, RC5 Asymmetric Large mathematical operations make it slower than symmetric algorithms No need for out of band key distribution (public keys are public!) Scales better since only a single key pair needed per individual Can provide authentication and nonrepudiation Examples: RSA, El Gamal, ECC, Diffie-Hellman problem with symmetric key cryptography DES (Data Encryption Standard) 64 bit key that is effectively 56 bits in strength Actual algorithm is called DEA (Data Encryption Algorithm) DES Modes Electronic Code Book Cipher Block Chaining (most commonly used for general purpose encryption) Cipher Feedback Output Feedback Counter Mode (used in IPSec) 3DES 112-bit effective key length Uses either 2 or 3 different smaller keys in one of several modes Modes EEE2/3 EDE2/3 AES NIST replaced DES in 1997 with this Uses the Rijndael algorithm Supports key/block sizes of 128, 192, and 256 bits Uses 10/12/14 rounds as block size increases IDEA (International Data Encryption Algorithm) Operates on 64 bit blocks in 8 rounds with 128 bit key Considered stronger than DES and is used in PGP Blowfish 64 bit block cipher with up to 448 bit key and 16 rounds Designed by Bruce Schneier RC4 Stream cipher with variable key size created by Ron Rivest RC5 Another Rivest cipher Block cipher with 32/64/128 bit blocks and keys up to 2048 bits RC6 Beefier version of RC5 submitted as AES candidate CAST 64 bit block cipher with keys between 40-128 bits with 12-16 rounds depending on key length CAST-256 used 128-bit blocks and keys from 128-256 bits using 48 rounds SAFER (Secure and Fast Encryption Routine) Set of patent-free algorithms in 64 and 128 bit block variants Variation used in Bluetooth Twofish Adapted version of Blowfish with 128 bit blocks, 128-256 bit keys and 16 rounds AES Finalist Kryptografie mit symmetrischem Schlüssel symmetric key cryptography symmetric key cryptography tutorial symmetric key cryptography example symmetric key cryptography vs asymmetric key cryptography symmetric and asymmetric key cryptography symmetric key cryptography Kryptografie mit symmetrischem Schlüssel Kryptographie mit symmetrischem Schlüssel Kryptographie mit symmetrischem Schlüssel Kryptografie mit symmetrischem Schlüssel und asymmetrische Schlüsselkryptographie symmetrische und asymmetrische Schlüsselkryptographie Kryptografie mit symmetrischem Schlüssel
Views: 39118 Zariga Tongy
Comparison of Hashing vs Encryption in MS SQL Server
 
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A video follow up to the blog http://enabledbusinesssolutions.com/blog/performance-comparison-between-plain-text-hashing-and-cell-level-encryption/ here I compare where hashing makes more sense than encryption and some pitfalls on using each of them.
Views: 2531 Jayanth Kurup
What is CRYPTOGRAPHIC ACCELERATOR? What does CRYPTOGRAPHIC ACCELERATOR mean?
 
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What is CRYPTOGRAPHIC ACCELERATOR? What does CRYPTOGRAPHIC ACCELERATOR mean? CRYPTOGRAPHIC ACCELERATOR meaning - CRYPTOGRAPHIC ACCELERATOR definition - CRYPTOGRAPHIC ACCELERATOR explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. In computing, a cryptographic accelerator is a co-processor designed specifically to perform computationally intensive cryptographic operations, doing so far more efficiently than the general-purpose CPU. Because many servers' system load consists mostly of cryptographic operations, this can greatly increase performance. Intel's AES-NI is by far the most common cryptographic accelerator in commodity hardware. VIA PadLock is another recent example. Several operating systems provide some support for cryptographic hardware. The BSD family of systems has the OpenBSD Cryptographic Framework (OCF), Linux systems have the Crypto API, Solaris OS has the Solaris Cryptographic Framework (SCF) and Microsoft Windows has the Microsoft CryptoAPI. Some cryptographic accelerators offer new machine instructions and can therefore be used directly by programs. Libraries such as OpenSSL and LibreSSL support some such cryptographic accelerators. Almost all Unix-like operating systems use OpenSSL or the fork LibreSSL as their cryptography library. These libraries use cryptographic accelerators such as AES-NI if available.
Views: 202 The Audiopedia
Checksum
 
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Checksum is a method of checking for errors in a communications system. I'm Mr. Woo and my channel is all about learning - I love doing it, and I love helping others to do it too. I guess that's why I became a teacher! I hope you get something out of these videos - I upload almost every weekday, so subscribe to find out when there's something new! For categorised playlists: http://www.misterwootube.com Main channel: http://youtube.com/misterwootube Discussion: http://facebook.com/misterwootube Worksheets and other resources: http://woo.jamesruse.nsw.edu.au
Views: 153729 Eddie Woo
Famous UNCRACKED Codes That STILL Exist!
 
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Check out these famous uncracked codes that still exist! From secret riddles to unsolved mysteries, this top 10 list contains cryptography that's still unexplained today! Subscribe For New Videos! http://goo.gl/UIzLeB Watch our "Most CRAZY Things Ancient Egyptians Did!" video here: https://youtu.be/T0zERiMJFQo Watch our "Most CRAZY Things Ancient Greeks Did!" video here: https://youtu.be/-JkhVvn_dow Watch our "REAL Evidence That Aliens EXIST!" video here: https://youtu.be/dtwJT2eilx0 10. Chinese Gold Bar Cipher In 1933, General Wang in Shanghai, China, allegedly received seven gold bars. These gold bars appear to represent metal certificates related to a bank deposit with a U.S. Bank. The gold bars themselves have pictures, Chinese writing, some form of script writing, and cryptograms in Latin letters. Not surprisingly, experts debate concerning the validity of the claim for the deposit. It may help to resolve the dispute if someone can decipher the cryptograms on the bars. Someone translated the Chinese writing, which discusses a transaction in excess of $300,000,000. It also refers to these gold bars, which weigh a total of 1.8 kilograms. The rest remains a mystery. 9. D’agapeyeff Cipher The D’Agapeyeff cipher is an as-yet unbroken cipher that appears in the first edition of Codes and Ciphers, an elementary book on cryptography published by the Russian-born English cartographer Alexander D’Agapeyeff in 1939. Offered as a “challenge cipher” at the end of the book, it was not included in later editions. D’Agapeyeff supposedly admitted later to having forgotten how he had encrypted it. Some argue that the failure of all attempts at decryption is due to D’Agapeyeff incorrectly encrypting the original text. However, it has also been argued that the cipher may still be successfully attacked using computational methods such as genetic algorithms. Whatever those are. 8. The Beale Ciphers If this next one isn’t a hoax then the person who solves it could become very, very rich. This question of authenticity has bothered cryptoanalysts ever since these ciphers first appeared in an 1885 pamphlet called The Beale Papers, which recounts a fantastic story of buried treasure. According to the pamphlet, a man named Thomas Jefferson Beale, a man no one has proven even existed, discovered gold during an 1816 expedition into the American West. The treasure, as the story goes, was then transported to Bedford County, Virginia, and buried. The gold's secret location was allegedly provided by three cryptograms, of which one was already cracked. Unfortunately, the cracked code only detailed the type of treasure there and not a specific location. To find out anything more specific would involve cracking the two other ciphers. The problem is that figuring it out requires comparing them to unknown historical texts. The decrypted cipher, for example, used the Declaration of Independence. The first number, 115, corresponds with the first letter of the 115th word in the Declaration: "instituted." That means 115 stands for "I." So what are the translation texts for the other two ciphers? No one knows, and they may very well not exist at all. There are also questions over whether the other ciphers may just be unintelligible, as if the whole thing was made up by the pamphlet's author decades after the gold was supposed to have been discovered. 7. Dorabella In 1897, a 40-year-old composer named Edward Elgar sent an encrypted letter to 23-year-old Dora Penny, the stepdaughter of one of his friends. Why he sent it is part of the mystery and can only be answered if anyone ever cracks the code. To figure it out would involve deciphering 87 characters all made of strings of semi-circles oriented in different directions. Attempts at translating the cipher yielded a message just short of gibberish. Experts say that shorter ciphers are always harder to solve. Another theory has it that the code is an example of a distinct private language shared only between Penny and Elgar. If that's the case, then solving it may be simply impossible, since no one but them would understand the references. In 2016, a police officer in Cleveland believes he’s cracked at least part of the code, revealing a line of melody. Inspector Mark Pitt read 100 books on the Dorabella Cipher; he hopes to write one on his discoveries. Whether or not that’s really the meaning, though, remains to be seen. Origins Explained is the place to be to find all the answers to your questions, from mysterious events and unsolved mysteries to everything there is to know about the world and its amazing animals!
Views: 1051532 Origins Explained
The concept of symmetric and asymmetric cryptography
 
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In this Video, Dr. Seema Batra, Assistant professor, Biyani Groups of Colleges, Jaipur, explains about the concept of symmetric and asymmetric cryptography. http://www.gurukpo.com/ http://www.biyanicolleges.org/
Views: 11981 Guru Kpo
Principles of Network Security and Cryptography
 
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In this video tutorial we study the basic principles of Network security and also see the concept of Cryptography by understanding a basic example. Principles of Network Security to be discussed in this video are as follows: Confidentiality Authentication Integrity Non-repudiation Access Control Availability We will also learn the concept of Cryptography in this tutorial. Here's the definition of Cryptography: Cryptography is the art of achieving security by encoding messages to make them non-readable This video is a continuation of the previous video so make sure you check that video as well so that you get to know some basics of Network security. Download the FREE Network Security App on Google Playstore for Android - https://play.google.com/store/apps/details?id=com.intelisenze.networksecuritytutorials Simple Snippets on Facebook- https://www.facebook.com/simplesnippets/ Simple Snippets on Instagram- https://www.instagram.com/simplesnipp... Simple Snippets Google Plus Page- https://plus.google.com/+SimpleSnippets Simple Snippets email ID- [email protected] Download my FREE Network Security Android App - https://play.google.com/store/apps/details?id=com.intelisenze.networksecuritytutorials For Classroom Coaching in Mumbai for Programming & other IT/CS Subjects Checkout UpSkill Infotech - https://upskill.tech/ UpSkill is an Ed-Tech Company / Coaching Centre for Information Technology / Computer Science oriented courses and offer coacing for various Degree courses like BSc.IT, BSc.CS, BCA, MSc.IT, MSc.CS, MCA etc. Contact via email /call / FB /Whatsapp for more info email - [email protected] We also Provide Certification courses like - Android Development Web Development Java Developer Course .NET Developer Course Check us out on Social media platforms like Facebook, Instagram, Google etc Facebook page - https://www.facebook.com/upskillinfotech/ Insta page - https://www.instagram.com/upskill_infotech/ Google Maps - https://goo.gl/maps/vjNtZazLzW82
Views: 20878 Simple Snippets
6 Types of Classification Algorithms
 
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Here are some of the most commonly used classification algorithms -- Logistic Regression, Naïve Bayes, Stochastic Gradient Descent, K-Nearest Neighbours, Decision Tree, Random Forest and Support Vector Machine. https://analyticsindiamag.com/7-types-classification-algorithms/ -------------------------------------------------- Get in touch with us: Website: www.analyticsindiamag.com Contact: [email protected] Facebook: https://www.facebook.com/AnalyticsIndiaMagazine/ Twitter: http://www.twitter.com/analyticsindiam Linkedin: https://www.linkedin.com/company-beta/10283931/ Instagram: https://www.instagram.com/analyticsindiamagazine/
22. Cryptography: Encryption
 
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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 continues with cryptography, introducing encryption methods. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 15430 MIT OpenCourseWare
Hashing Techniques Hash Function, Types of Hashing Techniques in Hindi and English
 
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Hashing Techniques Hash Function, Types of Hashing Techniques in Hindi and English * Direct Hashing * Modulo-Division Hashing * Mid-Square Hashing * Folding Hashing - Fold-Shift Hashing and Fold Boundary Hashing * PseudoRandom Hashing * Subtraction Hashing For Students of B.Tech, B.E, MCA, BCA, B.Sc., M.Sc., Courses - As Per IP University Syllabus and Other Engineering Courses
Views: 171892 Easy Engineering Classes
Algorithmic efficiency | Journey into cryptography | Computer Science | Khan Academy
 
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How can we improve the speed of a (deterministic) primality test? Watch the next lesson: https://www.khanacademy.org/computing/computer-science/cryptography/comp-number-theory/v/sieve-of-eratosthenes-prime-adventure-part-4?utm_source=YT&utm_medium=Desc&utm_campaign=computerscience Missed the previous lesson? https://www.khanacademy.org/computing/computer-science/cryptography/comp-number-theory/v/what-is-computer-memory-prime-adventure-part-7?utm_source=YT&utm_medium=Desc&utm_campaign=computerscience Computer Science on Khan Academy: Learn select topics from computer science - algorithms (how we solve common problems in computer science and measure the efficiency of our solutions), cryptography (how we protect secret information), and information theory (how we encode and compress information). About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s Computer Science channel: https://www.youtube.com/channel/UC8uHgAVBOy5h1fDsjQghWCw?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 25370 Khan Academy Labs
How hard is cracking a good encryption or hash ? Time needed to find one collision in SHA-256
 
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Video on collision , preimage and second preimage : https://www.youtube.com/watch?v=7cFIG04DsiE Full crytography playlist : https://www.youtube.com/watch?v=_Yw7QWbk9Vs&list=PLf8bMP4RWebLVGpUnhji9Olkj1jdXfzFd Article link of our website : https://hacksandsecurity.org/posts/how-much-time-it-will-take-find-one-collision-sha-256 How much time it would take to find one collision in SHA-256 ? How hard it is to crack SHA-256 ? How hard is cracking in real world ? How is lenght and randomness of input dependent on time taken to crack the encryption or hash output ? Is cracking digital signatures feasible ? How secure is modern cryptography ?
Views: 746 Hacks And Security
Ever wonder how Bitcoin (and other cryptocurrencies) actually work?
 
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Bitcoin explained from the viewpoint of inventing your own cryptocurrency. Videos like these made possible by patreon: https://patreon.com/3blue1brown Protocol Labs: https://protocol.ai/ Interested in contributing? https://protocol.ai/join/ Special thanks to the following patrons: http://3b1b.co/btc-thanks Some people have asked if this channel accepts contributions in cryptocurrency form as an alternative to Patreon. As you might guess, the answer is yes :). Here are the relevant addresses: ETH: 0x88Fd7a2e9e0E616a5610B8BE5d5090DC6Bd55c25 BTC: 1DV4dhXEVhGELmDnRppADyMcyZgGHnCNJ BCH: qrr82t07zzq5uqgek422s8wwf953jj25c53lqctlnw LTC: LNPY2HEWv8igGckwKrYPbh9yD28XH3sm32 Supplement video: https://youtu.be/S9JGmA5_unY Music by Vincent Rubinetti: https://soundcloud.com/vincerubinetti/heartbeat Here are a few other resources I'd recommend: Original Bitcoin paper: https://bitcoin.org/bitcoin.pdf Block explorer: https://blockexplorer.com/ Blog post by Michael Nielsen: https://goo.gl/BW1RV3 (This is particularly good for understanding the details of what transactions look like, which is something this video did not cover) Video by CuriousInventor: https://youtu.be/Lx9zgZCMqXE Video by Anders Brownworth: https://youtu.be/_160oMzblY8 Ethereum white paper: https://goo.gl/XXZddT Music by Vince Rubinetti: https://vincerubinetti.bandcamp.com/album/the-music-of-3blue1brown ------------------ 3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe, and click the bell to receive notifications (if you're into that). If you are new to this channel and want to see more, a good place to start is this playlist: http://3b1b.co/recommended Various social media stuffs: Website: https://www.3blue1brown.com Twitter: https://twitter.com/3Blue1Brown Patreon: https://patreon.com/3blue1brown Facebook: https://www.facebook.com/3blue1brown Reddit: https://www.reddit.com/r/3Blue1Brown
Views: 2256985 3Blue1Brown
How VPNs use tunneling and encryption
 
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How do VPNs protect your internet privacy? With tunneling and encryption! Watch the video to learn what that means. If you’d like to get an ExpressVPN subscription, visit the link for pricing: https://www.expressvpn.com/order?utm_source=youtube&utm_medium=video&utm_campaign=tunneling_encryption_video&utm_content=video_description ExpressVPN takes encryption very seriously, using AES (Advanced Encryption Standard) with 256-bit keys — also known as AES-256. It's the same encryption standard adopted by the U.S. government and used by security experts worldwide to protect classified information. For more on tunneling and encryption from ExpressVPN, check out: https://www.expressvpn.com/what-is-vpn/vpn-encryption?utm_source=youtube&utm_medium=video&utm_campaign=tunneling_encryption_video&utm_content=video_description ExpressVPN is a virtual private network service that allows you to amplify the entire internet. Get around censorship, secure your internet connection, and browse anonymously. An ExpressVPN subscription gets you access to 140+ server locations in more than 90 countries. And with apps for all your devices, you can take ExpressVPN with you wherever you go!
Views: 84801 ExpressVPN
Difference between symmetric and asymmetric key cryptography in bangla || নেটওয়ার্ক সিকিউরিটি
 
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Title: Difference between symmetric and asymmetric key cryptography in bangla || symmetric and asymmetric key encryption in bangla In this video symmetric and asymmetric key encryption is clearly described. The language used in this video is bangla but you'll also understand if you do not understand bangla. If you have any query please put comment. facebook links : https://www.facebook.com/jmshejan https://www.facebook.com/dsteaching/ Please subscribe my channel
Views: 1080 JM Shejan
#20 - Introduction to Encryption: Understanding Security Algorithm Use Cases
 
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More Information: http://embt.co/crx-blog This session will cover Symmetric-key and Public-key encryption, Hashing and there various use case scenarios. / This is a introduction to encryption it will cover Symmetric-key and Public-key encryption, and use cases of which one you should be using and when. It will also cover hashing including the new hashing classes, although this session will be very light on code. It will focus on understanding of the encryption concepts and when to use each. Robert Love State Of Utah CodeRage X 14-Oct-2015 http://www.embarcadero.com/coderage/
Quantum Computers Explained – Limits of Human Technology
 
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Where are the limits of human technology? And can we somehow avoid them? This is where quantum computers become very interesting. Check out THE NOVA PROJECT to learn more about dark energy: www.nova.org.au Support us on Patreon so we can make more stuff: https://www.patreon.com/Kurzgesagt?ty=h Get the music of the video here: https://soundcloud.com/epicmountain/quantum-computers https://epicmountainmusic.bandcamp.com/track/quantum-computers http://epic-mountain.com Wakelet: https://wakelet.com/wake/42ji9UMJzN?v=st Or follow us on social media or reddit: http://kurzgesagt.org https://www.reddit.com/r/kurzgesagt https://www.facebook.com/Kurzgesagt https://twitter.com/Kurz_Gesagt THANKS A LOT TO OUR LOVELY PATRONS FOR SUPPORTING US: Tamago231, H.H. Lewis, Kirin Tantinon, David, Max Lesterhuis, Marek Belski, Gisle, Colin Millions, Gregory Wolfe II, Lenoir Preminger, Abel X, Matt Knights, Amjad Al Taleb, Ian Bruce, Kris Wolfgramm, 麒麟 于, Christopher Shaw, 靖羊, Tomas Grolmus, Essena O’Neill, Kyle Messner, Pedro Devoto, Mark Radford, Ann-Marie Denham, Davide Pluda, Rik Vermeer, Justin Ritchie, Nicole White, Whireds, Claus Vallø, Jason Talley, Andrew Wu, Christian Dechery, Michael Howell, Michal Hanus, Cavit, Amary Wenger, JDKBot, Jason Eads, FreedomEagleAmerica, Roberto Maddaloni, TiagoF11, Harsha CS, Abhimanyu Yadav, Tracy Tobkin, Mike Fuchs, Elizabeth Mart, Jacob Wenger, Jeff Udall, Ricardo Affonso, Mauro Boffardi, Audrin Navarro, Troy Ross, Keith Tims, Santiago Perez, James, Jack Devlin, Chris Peters, Kenny Martin, Frederick Pickering, Lena Savelyeva, Ian Seale, Charles Ju, Brett Haugen, David Ramsey, Benjamin Dittes, Michelle Schoen, Albert Harguindey Sanchez, Michael King, Alex Kyriacou Alla Khvatova Thomas Rowan, Siim Sillamaa, David Bennell, Janzen,Bryn Farnsworth, Adam Recvlohe, Manuel Arredondo, Fred McIntyre, Maldock Manrique, Дмитрий, Ishita Bisht, Jake Ludwig, Zach Seggie, Casey Sloan, Myndert Papenhuyzen, rheingold3, AncientCulture, Orion Mondragon, Jan, Michael Kuperman, Alexander Argyropoulos Quantum Computers Explained – Limits of Human Technology Help us caption & translate this video! http://www.youtube.com/timedtext_cs_panel?c=UCsXVk37bltHxD1rDPwtNM8Q&tab=2
How Bitcoin Works Under the Hood
 
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A somewhat technical explanation of how Bitcoin works. Want more? Check out my new in-depth course on the latest in Bitcoin, Blockchain, and a survey of the most exciting projects coming out (Ethereum, etc): https://app.pluralsight.com/library/courses/bitcoin-decentralized-technology Lots of demos on how to buy, send, store (hardware, paper wallet). how to use javascript to send bitcoin. How to create Ethereum Smart Contract, much more. Shorter 5 min introduction: https://www.youtube.com/watch?v=t5JGQXCTe3c Written version: http://www.imponderablethings.com/2013/07/how-bitcoin-works-under-hood.html My Bitcoin address: 13v8NB9ScRa21JDi86GmnZ5d8Z4CjhZMEd Arabic translation by Ahmad Alloush Spanish caption translation by Borja Rodrigo, [email protected], DFJWgXdBCoQqo4noF4fyVhVp8R6V62XdJx Russian caption translation by Alexandra Miklyukova Italian voice over: http://youtu.be/1aEf3qr7UdE Italian captions translated by Simone Falcini, 1H5KdCnBooxfqpXtyQBBAKKRU7MkCZCVCe
Views: 2618780 CuriousInventor
SHA Algorithm Explained
 
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In this video, following topics covered: 1. Hash Function 2. SHA family 3. SHA-1 4. Sha-2 Website: http://www.allabouttesting.org Please share and subscribe this video Disclaimer: This video is for educational purpose only. Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use.
Views: 1834 All About Testing
How SSH Works
 
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A whiteboarding animation about secure shell protocol.
Views: 237530 Karol Cholewa
R1. Matrix Multiplication and the Master Theorem
 
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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: Ling Ren In this recitation, problems related to matrix multiplication and weighted interval scheduling are discussed. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 22305 MIT OpenCourseWare
Hashing and Hash table in data structure and algorithm
 
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This video lecture is produced by S. Saurabh. He is B.Tech from IIT and MS from USA. hashing in data structure hash table hash function hashing in dbms 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: 304460 saurabhschool
What is XSL ATTACK? What does XSL ATTACK mean? XSL ATTACK meaning, definition & explanation
 
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What is XSL ATTACK? What does XSL ATTACK mean? XSL ATTACK meaning - XSL ATTACK definition - XSL ATTACK explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ In cryptography, the eXtended Sparse Linearization (XSL) attack is a method of cryptanalysis for block ciphers. The attack was first published in 2002 by researchers Nicolas Courtois and Josef Pieprzyk. It has caused some controversy as it was claimed to have the potential to break the Advanced Encryption Standard (AES) cipher, also known as Rijndael, faster than an exhaustive search. Since AES is already widely used in commerce and government for the transmission of secret information, finding a technique that can shorten the amount of time it takes to retrieve the secret message without having the key could have wide implications. The method has a high work-factor, which unless lessened, means the technique does not reduce the effort to break AES in comparison to an exhaustive search. Therefore, it does not affect the real-world security of block ciphers in the near future. Nonetheless, the attack has caused some experts to express greater unease at the algebraic simplicity of the current AES. In overview, the XSL attack relies on first analyzing the internals of a cipher and deriving a system of quadratic simultaneous equations. These systems of equations are typically very large, for example 8,000 equations with 1,600 variables for the 128-bit AES. Several methods for solving such systems are known. In the XSL attack, a specialized algorithm, termed eXtended Sparse Linearization, is then applied to solve these equations and recover the key. The attack is notable for requiring only a handful of known plaintexts to perform; previous methods of cryptanalysis, such as linear and differential cryptanalysis, often require unrealistically large numbers of known or chosen plaintexts. Solving multivariate quadratic equations (MQ) over a finite set of numbers is an NP-hard problem (in the general case) with several applications in cryptography. The XSL attack requires an efficient algorithm for tackling MQ. In 1999, Kipnis and Shamir showed that a particular public key algorithm, known as the Hidden Field Equations scheme (HFE), could be reduced to an overdetermined system of quadratic equations (more equations than unknowns). One technique for solving such systems is linearization, which involves replacing each quadratic term with an independent variable and solving the resultant linear system using an algorithm such as Gaussian elimination. To succeed, linearization requires enough linearly independent equations (approximately as many as the number of terms). However, for the cryptanalysis of HFE there were too few equations, so Kipnis and Shamir proposed re-linearization, a technique where extra non-linear equations are added after linearization, and the resultant system is solved by a second application of linearization. Re-linearization proved general enough to be applicable to other schemes. In 2000, Courtois et al. proposed an improved algorithm for MQ known as XL (for eXtended Linearization), which increases the number of equations by multiplying them with all monomials of a certain degree. Complexity estimates showed that the XL attack would not work against the equations derived from block ciphers such as AES. However, the systems of equations produced had a special structure, and the XSL algorithm was developed as a refinement of XL which could take advantage of this structure. In XSL, the equations are multiplied only by carefully selected monomials, and several variants have been proposed. Research into the efficiency of XL and its derivative algorithms remains ongoing (Yang and Chen, 2004). Courtois and Pieprzyk (2002) observed that AES (Rijndael) and partially also Serpent could be expressed as a system of quadratic equations. The variables represent not just the plaintext, ciphertext and key bits, but also various intermediate values within the algorithm. The S-box of AES appears to be especially vulnerable to this type of analysis, as it is based on the algebraically simple inverse function. ...
Views: 265 The Audiopedia
IPsec VPN Tunnel
 
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Pre-setup: Usually this is the perimeter router so allow the firewall. Optional access-list acl permit udp source wildcard destination wildcard eq isakmp access-list acl permit esp source wildcard destination wildcard access-list acl permit ahp source wildcard destination wildcard You need to enable to securityk9 technology-package Router(config)#license boot module c2900 technology-package securityk9 Router(config)#reload Task 1: Configure the ISAKMP policy for IKE Phase 1 There are seven default isakmp policies. The most secure is the default. We will configure our own. You can remember this by HAGLE. Hash, Authentication, Group (DH), Lifetime, Encryption. Router(config)#crypto isakmp policy 1 Router(config-isakmp)#hash sha Router(config-isakmp)#authentication pre-share Router(config-isakmp)#group 5 Router(config-isakmp)#lifetime 3600 Router(config-isakmp)#encryption aes 256 We used a pre-shared key for authentication so we need to specify the password for the first phase. Router(config)#crypto isakmp key derpyisbestpony address 208.77.5.1 show crypto isakmp policy Task 2: Configure the IPsec Policy for IKE Phase 2 Configure the encryption and hashing algorithms that you will use for the data sent thought the IPsec tunnel. Hence the transform. Router(config)#crypto ipsec transform-set transform_name esp-aes esp-sha-hmac Task 3: Configure ACL to define interesting traffic Even though the tunnel is setup it doesn’t exist yet. Interesting traffic must be detected before IKE Phase 1 negotiations can begin. Allow the local lan to the remote lan. Router(config)#access-list 101 permit ip 192.168.0.0 0.0.0.255 10.0.0.0 0.0.0.255 show crypto isakmp sa Task 4: Configure a Crypto Map for the IPsec Policy Now that interesting traffic is defined and an IPsec transform set is configured, you need to bind them together with a crypto map. Rotuer(config)# crypto map map_name seq_num ipsec-isakmp What traffic will be interesting? The access-list we made before. Router(config-crypto-map)#match address 101 The transform-set we created earlier for the IPsec tunnel. Router(config-crypto-map)# set transform-set transform_name The peer router you’re connecting to. Router(config-crypto-map)#set peer 172.30.2.2 You need to set the type of DH you want to use. Router(config-crypto-map)#set pfs group5 How long these setting will last before it’s renegotiated Router(config-crypto-map)#set security-association lifetime seconds 900 Task 5: Apply the IPsec Policy Apply the crypto map to the interface. Router(config)#interface serial0/0/0 Router(config-if)#crypto map map_name show crypto map derpy: http://th03.deviantart.net/fs71/PRE/f/2012/302/6/1/derpy_hooves_by_freak0uo-d5jedxp.png twilight: http://fc03.deviantart.net/fs70/i/2012/226/e/5/twilight_sparkle_vector_by_ikillyou121-d56s0vc.png
Views: 12757 Derpy Networking
How SSL works tutorial - with HTTPS example
 
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How SSL works by leadingcoder. This is a full tutorial how to setup SSL that requires client certificate for reference: http://www.windowsecurity.com/articles/Client-Certificate-Authentication-IIS6.html .
Views: 1344423 tubewar
What is DETERMINISTIC ALGORITHM? What does DETERMINISTIC ALGORITHM mean?
 
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What is DETERMINISTIC ALGORITHM? What does DETERMINISTIC ALGORITHM mean? DETERMINISTIC ALGORITHM meaning - DETERMINISTIC ALGORITHM definition - DETERMINISTIC ALGORITHM explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ In computer science, a deterministic algorithm is an algorithm which, given a particular input, will always produce the same output, with the underlying machine always passing through the same sequence of states. Deterministic algorithms are by far the most studied and familiar kind of algorithm, as well as one of the most practical, since they can be run on real machines efficiently. Formally, a deterministic algorithm computes a mathematical function; a function has a unique value for any input in its domain, and the algorithm is a process that produces this particular value as output. Deterministic algorithms can be defined in terms of a state machine: a state describes what a machine is doing at a particular instant in time. State machines pass in a discrete manner from one state to another. Just after we enter the input, the machine is in its initial state or start state. If the machine is deterministic, this means that from this point onwards, its current state determines what its next state will be; its course through the set of states is predetermined. Note that a machine can be deterministic and still never stop or finish, and therefore fail to deliver a result. Examples of particular abstract machines which are deterministic include the deterministic Turing machine and deterministic finite automaton. A variety of factors can cause an algorithm to behave in a way which is not deterministic, or non-deterministic: If it uses external state other than the input, such as user input, a global variable, a hardware timer value, a random value, or stored disk data. If it operates in a way that is timing-sensitive, for example if it has multiple processors writing to the same data at the same time. In this case, the precise order in which each processor writes its data will affect the result. If a hardware error causes its state to change in an unexpected way. Although real programs are rarely purely deterministic, it is easier for humans as well as other programs to reason about programs that are. For this reason, most programming languages and especially functional programming languages make an effort to prevent the above events from happening except under controlled conditions. The prevalence of multi-core processors has resulted in a surge of interest in determinism in parallel programming and challenges of non-determinism have been well documented. A number of tools to help deal with the challenges have been proposed to deal with deadlocks and race conditions. It is advantageous, in some cases, for a program to exhibit nondeterministic behavior. The behavior of a card shuffling program used in a game of blackjack, for example, should not be predictable by players — even if the source code of the program is visible. The use of a pseudorandom number generator is often not sufficient to ensure that players are unable to predict the outcome of a shuffle. A clever gambler might guess precisely the numbers the generator will choose and so determine the entire contents of the deck ahead of time, allowing him to cheat; for example, the Software Security Group at Reliable Software Technologies was able to do this for an implementation of Texas Hold 'em Poker that is distributed by ASF Software, Inc, allowing them to consistently predict the outcome of hands ahead of time. These problems can be avoided, in part, through the use of a cryptographically secure pseudo-random number generator, but it is still necessary for an unpredictable random seed to be used to initialize the generator. For this purpose a source of nondeterminism is required, such as that provided by a hardware random number generator. Note that a negative answer to the P=NP problem would not imply that programs with nondeterministic output are theoretically more powerful than those with deterministic output. The complexity class NP (complexity) can be defined without any reference to nondeterminism using the verifier-based definition.
Views: 1510 The Audiopedia
10. Open Addressing, Cryptographic Hashing
 
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MIT 6.006 Introduction to Algorithms, Fall 2011 View the complete course: http://ocw.mit.edu/6-006F11 Instructor: Srini Devadas License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 78074 MIT OpenCourseWare
IOTA tutorial 18: Merkle Tree
 
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If you like this video and want to support me, go this page for my donation crypto addresses: https://www.youtube.com/c/mobilefish/about This is part 18 of the IOTA tutorial. In this video series different topics will be explained which will help you to understand IOTA. It is recommended to watch each video sequentially as I may refer to certain IOTA topics explained earlier. The main objective of this video is to provide you with some basic knowledge about the Merkle tree. The Merkle tree is used in IOTA's Masked Authenticated Messaging. IOTA's Masked Authenticated Messaging will be explained in IOTA tutorial 19. A hash tree or Merkle tree is a tree structure in which each leaf node is a hash of a block of data and each non-leaf node is a hash of its children. This results in a single hash called the Merkle root. If every node has two children, the tree is called a binary hash tree. Why use a Merkle tree? Why not hash all messages (m0-m15), append the hashed messages and then hash it all to get one root hash value. Bob get the root hash from a trusted source. If Alice wants to proof to Bob that m6 is not tampered with, she needs to send message m6 and all other hashed values: H(m0), H(m1), H(m2), H(m3), H(m4), H(m5), H(m7), H(m8), H(m9), H(m10), H(m11), H(m12), H(m13), H(m14) and H(m15) to Bob. Bob hashes message m6, append all hashes to a single string and hash this string to get one root hash. Bob compares this new root hash with the trusted source root hash to check if message m6 is not tampered with. In this example Alice has to provide 15 hashed values and the message m6 to Bob to prove that message m6 is not tampered with. A much better solution is using a Merkle tree (16 leaves) Again as before Bob gets the root hash from a trusted source. If Alice wants to proof that m6 is not tampered with, she needs to send m6 and 4 hashed values to Bob. With the received information Bob calculates the root hash value. Bob compares this root hash with the trusted source root hash to check if message m6 is not tampered with. In this example Alice only needs to provide 4 hashed values and the message m6 to Bob to prove that message m6 is not tampered with. Using a Merkle tree provides integrity and validity of your data using a small amount of data that a trusted authority has to maintain. This also means little memory / disk space is needed. If a Merkle tree has more leaves less hashed values are needed, in comparison to the number of leaves, to validate if a message is not tampered with. A perfect Merkle binary tree has the following properties: - The number of leaves is always 2n (n=0, 1, 2, 3,..). - Each node has 0 or 2 children. - All leaves are on the same level. In a perfect binary tree the following formulas can be applied: Total number of leaves = L = (N + 1) / 2 Total number of nodes = N = 2L - 1 Total number of levels = LV = log2(L) + 1 = (ln(L) / ln(2)) + 1 Number of leaves = L = 1 Number of nodes = N = 1 Number of levels = LV = 1 Number of leaves = L = 2 Number of nodes = N = 3 Number of levels = LV = 2 Number of leaves = L = 4 Number of nodes = N = 7 Number of levels = LV = 3 Number of leaves = L = 8 Number of nodes = N = 15 Number of levels = LV = 4 Number of leaves = L = 16 Number of nodes = N = 31 Number of levels = LV = 5 Check out all my other IOTA tutorial videos: https://goo.gl/aNHf1y Subscribe to my YouTube channel: https://goo.gl/61NFzK The presentation used in this video tutorial can be found at: https://www.mobilefish.com/developer/iota/iota_quickguide_tutorial.html #mobilefish #howto #iota
Views: 4458 Mobilefish.com
What is SIGNCRYPTION? What does SIGNCRYPTION mean? SIGNCRYPTION meaning & explanation
 
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What is SIGNCRYPTION? What does SIGNCRYPTION mean? SIGNCRYPTION meaning - SIGNCRYPTION pronunciation - SIGNCRYPTION definition - SIGNCRYPTION explanation - How to pronounce SIGNCRYPTION? Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ In cryptography, signcryption is a public-key primitive that simultaneously performs the functions of both digital signature and encryption. Encryption and digital signature are two fundamental cryptographic tools that can guarantee the confidentiality, integrity, and non-repudiation. Until 1997, they were viewed as important but distinct building blocks of various cryptographic systems. In public key schemes, a traditional method is to digitally sign a message then followed by an encryption (signature-then-encryption) that can have two problems: Low efficiency and high cost of such summation, and the case that any arbitrary scheme cannot guarantee security. Signcryption is a relatively new cryptographic technique that is supposed to perform the functions of digital signature and encryption in a single logical step and can effectively decrease the computational costs and communication overheads in comparison with the traditional signature-then-encryption schemes. Signcryption provides the properties of both digital signatures and encryption schemes in a way that is more efficient than signing and encrypting separately. This means that at least some aspect of its efficiency (for example the computation time) is better than any hybrid of digital signature and encryption schemes, under a particular model of security. Note that sometimes hybrid encryption can be employed instead of simple encryption, and a single session-key reused for several encryptions to achieve better overall efficiency across many signature-encryptions than a signcryption scheme but the session-key reuse causes the system to lose security under even the relatively weak CPA model. This is the reason why a random session key is used for each message in a hybrid encryption scheme but for a given level of security (i.e., a given model, say CPA), a signcryption scheme should be more efficient than any simple signature-hybrid encryption combination.
Views: 85 The Audiopedia
Identity 101: Passwords, Hashing and Encoding
 
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When working with passwords, many times people in the industry use the terms encryption, passwords, hashing and encoding interchangeably--but in reality, they are quite different. There's a time and a place to use each. In this video I'm going to define these 3 terms, provide you use examples of each, and explain how you can utilize password storage to ensure your company's data remains safe.
Views: 897 Identropy
Secrets Hidden in Images (Steganography) - Computerphile
 
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Secret texts buried in a picture of your dog? Image Analyst Dr. Mike Pound explains the art of steganography in digital images. The Problem with JPEG: https://youtu.be/yBX8GFqt6GA The Bayer Filter: https://youtu.be/LWxu4rkZBLw Super Computer & the Milky Way: https://youtu.be/5KEhhW8TOGk JPEG Discrete Cosine Transform (DCT): https://youtu.be/Q2aEzeMDHMA http://www.facebook.com/computerphile https://twitter.com/computer_phile This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: http://bit.ly/nottscomputer Computerphile is a sister project to Brady Haran's Numberphile. More at http://www.bradyharan.com
Views: 571829 Computerphile
SSL TLS HTTPS process explained in 7 minutes
 
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SSL TLS HTTPS process explained in 7 minutes
Views: 329617 Johannes Bickel
23. Cache-Oblivious Algorithms: Medians & Matrices
 
01:20:28
MIT 6.046J Design and Analysis of Algorithms, Spring 2015 View the complete course: http://ocw.mit.edu/6-046JS15 Instructor: Erik Demaine In this lecture, Professor Demaine introduces cache-oblivious algorithms. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 8021 MIT OpenCourseWare
The Power of Theory in the Practice of Hashing with Focus on Similarity Estimation
 
01:07:17
A Google TechTalk, 3/8/18, presented by Mikkel Thorup (University of Copenhagen) Talks from visiting speakers on Algorithms, Theory, and Optimization
Views: 1178 GoogleTechTalks
7. Counting Sort, Radix Sort, Lower Bounds for Sorting
 
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MIT 6.006 Introduction to Algorithms, Fall 2011 View the complete course: http://ocw.mit.edu/6-006F11 Instructor: Erik Demaine License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 195515 MIT OpenCourseWare
What is CUSTOM HARDWARE ATTACK? What does CUSTOM HARDWARE ATTACK mean?
 
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What is CUSTOM HARDWARE ATTACK? What does CUSTOM HARDWARE ATTACK mean? CUSTOM HARDWARE ATTACK meaning - CUSTOM HARDWARE ATTACK definition - CUSTOM HARDWARE ATTACK explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ In cryptography, a custom hardware attack uses specifically designed application-specific integrated circuits (ASIC) to decipher encrypted messages. Mounting a cryptographic brute force attack requires a large number of similar computations: typically trying one key, checking if the resulting decryption gives a meaningful answer and trying the next key if it does not. Computers can perform these calculations at a rate of millions per second, and thousands of computers can be harnessed together in a distributed computing network. But the number of computations required on average grows exponentially with the size of the key and for many problems standard computers are not fast enough. On the other hand, many cryptographic algorithms lend themselves to fast implementation in hardware, i.e. networks of logic circuits or "gates." Integrated circuits (ICs) are constructed of these gates and often can execute cryptographic algorithms hundreds of times faster than a general purpose computer. Each IC can contain large numbers of gates (hundreds of millions in 2005) and the number continues to grow according to Moore's law. Thus the same decryption circuit, or cell, can be replicated thousands of times on one IC. The communications requirements for these ICs are very simple. Each must be initially loaded with a starting point in the key space and, in some situations, with a comparison test value (see known plaintext attack). Output consists of a signal that the IC has found an answer and the successful key. Since ICs lend themselves to mass production, thousands or even millions of ICs can be applied to a single problem. The ICs themselves can be mounted in printed circuit boards. A standard board design can be used for different problems since the communication requirements for the chips are the same. Wafer-scale integration is another possibility. The primary limitations on this method are the cost of chip design, IC fabrication, floor space, electric power and thermal dissipation. An alternative approach is to use FPGAs (field-programmable gate arrays); these are slower and more expensive per gate, but can be reprogrammed for different problems. COPACOBANA (Cost-Optimized Parallel COde Breaker) is one such machine, consisting of 120 FPGAs of type Xilinx Spartan3-1000 which run in parallel. The earliest custom hardware attack may have been the Bombe used to recover Enigma machine keys in World War II. In 1998, a custom hardware attack was mounted against the Data Encryption Standard cipher by the Electronic Frontier Foundation. Their "Deep Crack" machine cost U.S. $250,000 to build and decrypted the DES Challenge II-2 test message after 56 hours of work. The only other confirmed DES cracker was the COPACOBANA machine (Cost-Optimized PArallel COde Breaker) built in 2006. Unlike Deep Crack, COPACOBANA consist of commercially available, reconfigurable integrated circuits. COPACOBANA costs about $10,000 to build and will recover a DES key in under 6.4 days on average. The cost decrease by roughly a factor of 25 over the EFF machine is an impressive example for the continuous improvement of digital hardware. Adjusting for inflation over 8 years yields an even higher improvement of about 30x. Since 2007, SciEngines GmbH, a spin-off company of the two project partners of COPACOBANA has enhanced and developed successors of COPACOBANA. In 2008 their COPACOBANA RIVYERA reduced the time to break DES to the current record of less than one day, using 128 Spartan-3 5000's. It is generally believed that large government code breaking organizations, such as the U.S. National Security Agency, make extensive use of custom hardware attacks, but no examples have been declassified as of 2005.
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