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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: 419699 itfreetraining
Public key cryptography - Diffie-Hellman Key Exchange (full version)
 
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The history behind public key cryptography & the Diffie-Hellman key exchange algorithm. We also have a video on RSA here: https://www.youtube.com/watch?v=wXB-V_Keiu8
Views: 587426 Art of the Problem
Cryptography: Transposition Cipher
 
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This lesson explains how to encrypt and decrypt a message using a transposition cipher. Site: http://mathispower4u.com
Views: 51214 Mathispower4u
Public Key Cryptography: Diffie-Hellman Key Exchange (short version)
 
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This is a segment of this full video: https://www.youtube.com/watch?v=YEBfamv-_do Diffie-Hellman key exchange was one of the earliest practical implementations of key exchange within the field of cryptography. It relies on the discrete logarithm problem. This test clip will be part of the final chapter of Gambling with Secrets!
Views: 435815 Art of the Problem
Chapter 2, part 3: Crypto Basics --- double transposition, one-time pad
 
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Information Security: Principles and Practice, 2nd edition, by Mark Stamp Chapter 2: Crypto Basics Sections 2.3.4-2.3.5 double transposition, one-time pad Class Lecture, 2011
Views: 18745 Mark Stamp
What is KEY DISTRIBUTION? What does KEY DISTRIBUTION mean? KEY DISTRIBUTION meaning & explanation
 
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What is KEY DISTRIBUTION? What does KEY DISTRIBUTION mean? KEY DISTRIBUTION meaning - KEY DISTRIBUTION definition - KEY DISTRIBUTION 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 symmetric key cryptography, both parties must possess a secret key which they must exchange prior to using any encryption. Distribution of secret keys has been problematic until recently, because it involved face-to-face meeting, use of a trusted courier, or sending the key through an existing encryption channel. The first two are often impractical and always unsafe, while the third depends on the security of a previous key exchange. In public key cryptography, the key distribution of public keys is done through public key servers. When a person creates a key-pair, they keep one key private and the other, known as the public-key, is uploaded to a server where it can be accessed by anyone to send the user a private, encrypted, message. Secure Sockets Layer (SSL) uses Diffie–Hellman key exchange if the client does not have a public-private key pair and a published certificate in the public key infrastructure, and Public Key Cryptography if the user does have both the keys and the credential. Key distribution is an important issue in wireless sensor network (WSN) design. There are many key distribution schemes in the literature that are designed to maintain an easy and at the same time secure communication among sensor nodes. The most accepted method of key distribution in WSNs is key predistribution, where secret keys are placed in sensor nodes before deployment. When the nodes are deployed over the target area, the secret keys are used to create the network. For more info see: key distribution in wireless sensor networks. Key distribution and key storage are more problematic in the cloud due to the transitory nature of the agents on it. Secret sharing can be used to store keys at many different servers on the cloud. In secret sharing, a secret is used as a seed to generate a number of distinct secrets, and the pieces are distributed so that some subset of the recipients can jointly authenticate themselves and use the secret information without learning what it is. But rather than store files on different servers, the key is parceled out and its secret shares stored at multiple locations in a manner that a subset of the shares can regenerate the key. Secret sharing is used in cases where one wishes to distribute a secret among N shares so that M N of them (M of N) can regenerate the original secret, but no smaller group up to M - 1 can do so.
Views: 42 The Audiopedia
Quantum Cryptography Explained
 
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This episode is brought to you by Squarespace: http://www.squarespace.com/physicsgirl With recent high-profile security decryption cases, encryption is more important than ever. Much of your browser usage and your smartphone data is encrypted. But what does that process actually entail? And when computers get smarter and faster due to advances in quantum physics, how will encryption keep up? http://physicsgirl.org/ ‪http://twitter.com/thephysicsgirl ‪http://facebook.com/thephysicsgirl ‪http://instagram.com/thephysicsgirl http://physicsgirl.org/ Help us translate our videos! http://www.youtube.com/timedtext_cs_panel?c=UC7DdEm33SyaTDtWYGO2CwdA&tab=2 Creator/Editor: Dianna Cowern Writer: Sophia Chen Animator: Kyle Norby Special thanks to Nathan Lysne Source: http://gva.noekeon.org/QCandSKD/QCand... http://physicsworld.com/cws/article/n... https://epic.org/crypto/export_contro... http://fas.org/irp/offdocs/eo_crypt_9... Music: APM and YouTube
Views: 258510 Physics Girl
The one-time pad | Journey into cryptography | Computer Science | Khan Academy
 
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The perfect cipher Watch the next lesson: https://www.khanacademy.org/computing/computer-science/cryptography/crypt/v/frequency-stability?utm_source=YT&utm_medium=Desc&utm_campaign=computerscience Missed the previous lesson? https://www.khanacademy.org/computing/computer-science/cryptography/crypt/v/polyalphabetic-cipher?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: 412569 Khan Academy
Module 5: What is a cipher (substitution and transposition)?
 
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There are many different types of ciphers The examples shown in this video are substitution and transposition ciphers This video shows how normal plain-text is converted to cipher-text References: Substitution cipher. (n.d.). Retrieved February 18, 2015, from https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Substitution_cipher.html
Views: 19796 Simple Security
What is Encryption and How Does it Work? | Mashable Explains
 
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Encryption & decryption technology protects your e-mails, banking transactions, and even those questionable Etsy purchases. So how does it work, exactly? Hey, Mashable Explains is back! We've got new episodes coming to you every Thursday, so make sure to subscribe! http://on.mash.to/subscribe Sorry, you’re addicted to the Internet https://www.youtube.com/watch?v=NpluiONwJLg Why do we love Snapchat so much? https://www.youtube.com/watch?v=rZln9XNTOtw MASHABLE ON YOUTUBE Subscribe to Mashable: http://on.mash.to/subscribe Mashable Explains Playlist: https://www.youtube.com/playlist?list=PLSKUhDnoJjYn0TV9V84C4Wr2DjKPc492c MASHABLE ACROSS THE WEB Mashable.com: http://on.mash.to/1hCcRpl Facebook: http://on.mash.to/1KkCTIP Twitter: http://on.mash.to/1Udp1kz Tumblr: http://on.mash.to/1NBBijY Instagram: http://on.mash.to/1U6D40z Google+: http://on.mash.to/1i27L5R Mashable is a leading global media company that informs, inspires and entertains the digital generation.
Views: 88994 Mashable
Information & Network Security Lecture -- DES simple Explanation (Eng-Hindi)
 
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-~-~~-~~~-~~-~- Please watch: "PL vs FOL | Artificial Intelligence | (Eng-Hindi) | #3" https://www.youtube.com/watch?v=GS3HKR6CV8E -~-~~-~~~-~~-~-
Views: 72160 Well Academy
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: 14673 MIT OpenCourseWare
One Time Pad - 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: 37895 Udacity
cryptography - The One Time Pad
 
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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: 1627 intrigano
RSA vs ECC
 
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Public Cryptosystem
Views: 5796 Israel Reyes
Encryption Technique : One time Pad with example
 
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Classical Encryption Technique One time Pad GTU SEM 6 Information Security CSE /IT
Views: 24333 Dhruvin Shah
Introduction to Cryptography
 
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Introduction to Cryptography, includes Modular Arithmetic and Numerical Representation tutorial
Views: 1028 Daniel Rees
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: 783457 3Blue1Brown
Elliptic Curve Cryptography Overview
 
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John Wagnon discusses the basics and benefits of Elliptic Curve Cryptography (ECC) in this episode of Lightboard Lessons. Check out this article on DevCentral that explains ECC encryption in more detail: https://devcentral.f5.com/articles/real-cryptography-has-curves-making-the-case-for-ecc-20832
Views: 134416 F5 DevCentral
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: 62154 MIT OpenCourseWare
Why It's So Hard For The Government To Hack Your Phone
 
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The FBI is currently in a battle with Apple to allow encrypted phones be unlocked, but how does encryption even work? How Powerful Is Apple? ►►►► http://bit.ly/1OBOqRk Sign Up For The TestTube Newsletter Here ►►►► http://bit.ly/1myXbFG How Secure Are Fingerprint Scanners? ►►►►http://bit.ly/1R7K5qX Read More: ADVANCED ENCRYPTION STANDARD (AES) http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf "The Advanced Encryption Standard (AES) specifies a FIPS-approved cryptographic algorithm that can be used to protect electronic data. The AES algorithm is a symmetric block cipher that can encrypt (encipher) and decrypt (decipher) information." "This standard may be used by Federal departments and agencies when an agency determines that sensitive (unclassified) information" Analysis of Avalanche Effect in Plaintext of DES using Binary Codes http://www.ijettcs.org/Volume1Issue3/IJETTCS-2012-10-25-097.pdf "Cryptography provides a method for securing and authenticating the transmission of information across insecure communication channels." "Symmetric keys encryption or secret key encryption identical key is used by sender and receiver." "Data can be recovered from cipher only by using exactly the same key used to encipher it." Advanced Encryption Standard (AES) http://searchsecurity.techtarget.com/definition/Advanced-Encryption-Standard "The Advanced Encryption Standard became effective as a federal government standard in 2002" "ES is one of the Suite B cryptographic algorithms used by NSA's Information Assurance Directorate in technology approved for protecting national security systems." iOS Security http://www.apple.com/business/docs/iOS_Security_Guide.pdf#page=12 "On mobile devices, speed and power efficiency are critical. Cryptographic operations are complex and can introduce performance or battery life problems if not designed and implemented with these priorities in mind." "Every iOS device has a dedicated AES 256 crypto engine built into the DMA path between the flash storage and main system memory, making file encryption highly efficient" ____________________ DNews is dedicated to satisfying your curiosity and to bringing you mind-bending stories & perspectives you won't find anywhere else! New videos twice daily. Watch More DNews on TestTube http://testtube.com/dnews Subscribe now! http://www.youtube.com/subscription_center?add_user=dnewschannel DNews on Twitter http://twitter.com/dnews Trace Dominguez on Twitter https://twitter.com/tracedominguez Julia Wilde on Twitter https://twitter.com/julia_sci DNews on Facebook https://facebook.com/DiscoveryNews DNews on Google+ http://gplus.to/dnews Discovery News http://discoverynews.com Download the TestTube App: http://testu.be/1ndmmMq Sign Up For The TestTube Mailing List: http://dne.ws/1McUJdm
Views: 322864 Seeker
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: 2601218 CuriousInventor
Cryptography, Perfect Secrecy and One Time Pads | Two Minute Papers #25
 
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Cryptography helps us to communicate securely with someone in the presence of third parties. We use this when we do for instance, online banking or even as mundane tasks as reading our gmail. In this episode, we review some cipher techniques such as the Caesar cipher, rot13, and as we find out how easy they are to break, we transition to the only known technique to yield perfect secrecy: one time pads. Are they practical enough for everyday use? How do our findings relate to extraterrestrial communications? Both questions get answered in the video. Additional comment: "In modern certification cryptanalysis, if a cipher output can be distinguished from a PRF (pseudo random functions), it's enough to deem it broken." - Source: https://twitter.com/cryptoland/status/666721478675668993 ______________________ The paper "Cipher printing telegraph systems: For secret wire and radio telegraphic communications" is available here: http://math.boisestate.edu/~liljanab/Math509Spring10/vernam.pdf You can try encrypting your own messages on these websites: http://practicalcryptography.com/ciphers/caesar-cipher/ http://rot13.com/index.php http://www.braingle.com/brainteasers/codes/onetimepad.php Subscribe if you would like to see more of these! - http://www.youtube.com/subscription_center?add_user=keeroyz The thumbnail background was created by Adam Foster (CC BY 2.0) - https://flic.kr/p/b99vsi Splash screen/thumbnail design: Felícia Fehér - http://felicia.hu Károly Zsolnai-Fehér's links: Patreon → https://www.patreon.com/TwoMinutePapers Facebook → https://www.facebook.com/TwoMinutePapers/ Twitter → https://twitter.com/karoly_zsolnai Web → https://cg.tuwien.ac.at/~zsolnai/
Views: 9659 Two Minute Papers
What is RELATED-KEY ATTACK? What does RELATED-KEY ATTACK mean? RELATED-KEY ATTACK meaning
 
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What is RELATED-KEY ATTACK? What does RELATED-KEY ATTACK mean? RELATED-KEY ATTACK meaning - RELATED-KEY ATTACK definition - RELATED-KEY 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 related-key attack is any form of cryptanalysis where the attacker can observe the operation of a cipher under several different keys whose values are initially unknown, but where some mathematical relationship connecting the keys is known to the attacker. For example, the attacker might know that the last 80 bits of the keys are always the same, even though he doesn't know, at first, what the bits are. This appears, at first glance, to be an unrealistic model; it would certainly be unlikely that an attacker could persuade a human cryptographer to encrypt plaintexts under numerous secret keys related in some way. KASUMI is an eight round, 64-bit block cipher with a 128-bit key. It is based upon MISTY1, and was designed to form the basis of the 3GPP (3rd Generation Partnership Project) confidentiality and integrity algorithms. 3GPP is the body standardizing the next generation of mobile telephony. Mark Blunden and Adrian Escott described differential related key attacks on five and six rounds of KASUMI. Differential attacks were introduced by Biham and Shamir. Related key attacks were first introduced by Biham. Differential related key attacks are discussed in Kelsey et al. An important example of a cryptographic protocol that failed because of a related-key attack is Wired Equivalent Privacy (WEP) used in WiFi wireless networks. Each client Wi-Fi network adapter and wireless access point in a WEP-protected network shares the same WEP key. Encryption uses the RC4 algorithm, a stream cipher. It is essential that the same key never be used twice with a stream cipher. To prevent this from happening, WEP includes a 24-bit initialization vector (IV) in each message packet. The RC4 key for that packet is the IV concatenated with the WEP key. WEP keys have to be changed manually and this typically happens infrequently. An attacker therefore can assume that all the keys used to encrypt packets share a single WEP key. This fact opened up WEP to a series of attacks which proved devastating. The simplest to understand uses the fact that the 24-bit IV only allows a little under 17 million possibilities. Because of the birthday paradox, it is likely that for every 4096 packets, two will share the same IV and hence the same RC4 key, allowing the packets to be attacked. More devastating attacks take advantage of certain weak keys in RC4 and eventually allow the WEP key itself to be recovered. In 2005, agents from the U.S. Federal Bureau of Investigation publicly demonstrated the ability to do this with widely available software tools in about three minutes. One approach to preventing related-key attacks is to design protocols and applications so that encryption keys will never have a simple relationship with each other. For example, each encryption key can be generated from the underlying key material using a cryptographic hash function or other key derivation function. For example, a replacement for WEP, Wi-Fi Protected Access (WPA), uses three levels of keys: master key, working key and RC4 key. The master WPA key is shared with each client and access point and is used in a protocol called TKIP to create new working keys frequently enough to thwart known attack methods. The working keys are then combined with a longer, 48-bit IV to form the RC4 key for each packet. This design mimics the WEP approach enough to allow WPA to be used with first-generation Wi-Fi network cards, some of which implemented portions of WEP in hardware. However, not all first-generation access points can run WPA. Another, more conservative approach is to employ a cipher designed to prevent related-key attacks altogether, usually by incorporating a strong key schedule. A newer version of Wi-Fi Protected Access, WPA2, uses the AES block cipher instead of RC4, in part for this reason. There are related-key attacks against AES, but unlike those against RC4, they're far from practical to implement, and WPA2's key generation functions may provide some security against them. Many older network cards cannot run WPA2.
Views: 94 The Audiopedia
Polygraphic Part 2 - Hill Ciphers Examples/Encryption/Decryption
 
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A beginner's guide to Polygraphic Ciphers, Part 2. (Hill Ciphers Examples/Encryption/Decryption)
Views: 97412 Daniel Rees
Hash Functions
 
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0:00-4:15 - A conceptual overview of hash functions and their requirements. 4:15-end - Hash functions in digital signatures use. For review on how RSA signatures work, see: https://www.youtube.com/watch?v=DIfOvWymmP0 Questions? Feel free to post them in the comments and I'll do my best to answer!
Views: 16106 Theoretically
What is CERTIFICATE-BASED ENCRYPTION? What does CERTIFICATE-BASED ENCRYPTION mean?
 
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What is CERTIFICATE-BASED ENCRYPTION? What does CERTIFICATE-BASED ENCRYPTION mean? CERTIFICATE-BASED ENCRYPTION meaning - CERTIFICATE-BASED ENCRYPTION definition - CERTIFICATE-BASED ENCRYPTION 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 Certificate-based encryption is a system in which a certificate authority uses ID-based cryptography to produce a certificate. This system gives the users both implicit and explicit certification, the certificate can be used as a conventional certificate (for signatures, etc.), but also implicitly for the purpose of encryption. A user Alice can doubly encrypt a message using another user's (Bob) public key and his (Bob's) identity. This means that the user (Bob) cannot decrypt it without a currently valid certificate and also that the certificate authority cannot decrypt the message as they don't have the user's private key (i.e., there is no implicit escrow as with ID-based cryptography, as the double encryption means they cannot decrypt it solely with the information they have).Certificate is the trust between two parties. Key revocation can be added to the system by requiring a new certificate to be issued as frequently as the level of security requires. Because the certificate is "public information", it does not need to be transmitted over a secret channel. The downside of this is the requirement for regular communication between users and the certificate authority, which means the certificate authority is more vulnerable to electronic attacks (such as denial-of-service attacks) and also that such attacks could effectively stop the system from working. This risk can be partially but not completely reduced by having a hierarchy of multiple certificate authorities. The best example of practical use of certificate-based encryption is Content Scrambling System (CSS), which is used to encode DVD movies in such a way as to make them playable only in a part of the world where they are sold. However, the fact that the region decryption key is stored on the hardware level in the DVD players substantially weakens this form of protection.
Views: 34 The Audiopedia
What is PIGGY BANK CRYPTOGRAPHY? What does PIGGY BANK CRYPTOGRAPHY mean?
 
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What is PIGGY BANK CRYPTOGRAPHY? What does PIGGY BANK CRYPTOGRAPHY mean? PIGGY BANK CRYPTOGRAPHY meaning - PIGGY BANK CRYPTOGRAPHY definition - PIGGY BANK CRYPTOGRAPHY 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 Piggy bank cryptography is a digital emulation of a piggy bank. It uses an encrypted message as a carrier into which valuable secrets can be inserted and later recovered by the person who issued the message. A typical protocol works as follows: Bob, who wishes to obtain secret information from Alice, uses public key cryptography to encrypt some random data with his own public key. He sends the result to Alice. Alice creates a single-use key pair. She injects both her secret and her new decryption key into Bob's message. She then writes a signed note that describes what she has injected. She encrypts the note with her new encryption key, and sends the modified message and note to Bob. Bob decrypts the modified message to obtain both the secret and Alice's decryption key. He uses her decryption key to read the note and verify that Alice sent the secret. In this scheme, Bob does not necessarily require a public key from Alice, although he does require her to sign her note in such a way that he can verify her authorship. Piggy bank cryptography has been proposed for authenticating parties to detect man-in-the-middle attack. The piggy bank paradigm can be used to implement asymmetric as well as double-lock cryptography.
Views: 19 The Audiopedia
Double Transposition Cipher ( Math CID 2014)
 
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Double Transposition Cipher Tan Jia Qi 4G Terri Yip 4I Janice Kow 4R Soo Hui Min 4S
Views: 1330 Janice Kow
What is POST-QUANTUM CRYPTOGRAPHY? What does POST-QUANTUM CRYPTOGRAPHY mean?
 
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What is POST-QUANTUM CRYPTOGRAPHY? What does POST-QUANTUM CRYPTOGRAPHY mean? POST-QUANTUM CRYPTOGRAPHY meaning - POST-QUANTUM CRYPTOGRAPHY definition - POST-QUANTUM CRYPTOGRAPHY 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 Post-quantum cryptography refers to cryptographic algorithms (usually public-key algorithms) that are thought to be secure against an attack by a quantum computer. This is not true for the most popular public-key algorithms, which can be efficiently broken by a sufficiently large quantum computer. The problem with the currently popular algorithms is that their security relies on one of three hard mathematical problems: the integer factorization problem, the discrete logarithm problem or the elliptic-curve discrete logarithm problem. All of these problems can be easily solved on a sufficiently powerful quantum computer running Shor's algorithm. Even though current, publicly known, experimental quantum computers are too small to attack any real cryptographic algorithm, many cryptographers are designing new algorithms to prepare for a time when quantum computing becomes a threat. This work has gained greater attention from academics and industry through the PQCrypto conference series since 2006 and more recently by several workshops on Quantum Safe Cryptography hosted by the European Telecommunications Standards Institute (ETSI) and the Institute for Quantum Computing. In contrast to the threat quantum computing poses to current public-key algorithms, most current symmetric cryptographic algorithms and hash functions are considered to be relatively secure against attacks by quantum computers. While the quantum Grover's algorithm does speed up attacks against symmetric ciphers, doubling the key size can effectively block these attacks. Thus post-quantum symmetric cryptography does not need to differ significantly from current symmetric cryptography.
Views: 129 The Audiopedia
What Is An IV Attack?
 
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An iv attack is usually associated with which of the following hash why use an initialization vector (iv)? Cryptography stack. Obviously, 104 bit keys are more resistant to brute force attacks than 40 a url? Q informit articles article. Wifi attack vectors hal berghel. 10 sep 2014 in this video, you ll learn how a poorly implemented in cryptography, an initialization vector (iv) or starting variable (sv) is a fixed size input to a about plaintext of some block that was encrypted with the same key before. Comptia security plus mock test q1192. Wireless iv attacks comptia security sy0 401 3. This is known as the tls cbc iv attack, also called beast attack 10 sep 2014an initialization vector (iv) an on wireless networks. Googleusercontent search. The use of an iv prevents repetition in data encryption, making it more difficult for a hacker using dictionary attack to find patterns and break cipher. Comptia security sy0 401 free mock exam test. A number of attacks become particular, when using turing with a 256 bit secret key and 128 iv, chosen iv attack against rc4 proposed in [7] is good illustration this point modifying the initialization vector (iv) cbc encryptedwe show that can be. It modifies the iv of an encrypted wireless packet during transmission. What is an iv attack? Youtube. For example, a sequence might appear twice or more within the body of message as an initialization vector (iv) that wep uses for encryption is 24 bit, which quite weak and means ivs are reused with same key generally speaking, iv whatever piece data needed to begin given often public, there any attacks involve tag attack. Initialization vector attacks on the ipsec protocol suite bilkent a chosen iv attack against turing air snort weak wireless lan cisco certified expert. Wep vulnerabilities—Wired equivalent privacy iv collisions. A serious threat for ipsec if is not in particular, when using turing with a 256 bit secret key and 128 iv, we present an attack that requires the ability to choose 2 37 iv then recovers 18 aug 2017 ifftitittititl ii iii iiiii hi cisco based on fluhrer mantin shamir paper cbc, xored (noted by ' below) plain text, run making ivs unpredictable thwarts this attack, easy way 27 may 2016 while sounds like long shot, it actually known tls 1. Attacks threats and attacks against your wireless iv comptia security sy0 401 3. Aspx%3fp%3d102230%26seqnum%3d6&sa u&ved 0ahukewis3jex07jbahvxwx0khdivdvi4chawcbkwaq&usg aovvaw0ybmbncfzvqrgor_wmrtoz" target "_blank"iv collisions. Iv) and a 40 bit wep key. Professor professormesser security plus wireless iv attacks "imx0m" url? Q webcache. Obviously, 104 bit keys are more resistant to brute force attacks than 40 23 dec 2003 since the iv is sent in clear text, an attacker who keeps track of all traffic can identify when collisions occur. Vulnerability called tls cbc iv or beast attack that was first discovered in 8 sep 2013 when encrypting with mode, the initialization vector (iv) is he can use a chosen pla
Views: 35 E Answers
Your Family Tree Explained
 
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Discuss this video: http://www.reddit.com/r/CGPGrey/comments/27a9yn/your_family_tree_explained/ Family chart: http://www.cgpgrey.com/blog/family-tree Footnote * https://www.youtube.com/watch?v=U6ViKuXd5qQ Support: https://subbable.com/cgpgrey/ Website: http://www.cgpgrey.com/ Special thanks: Shaun May Gustavo Maronato Ryan Hendry Dawid van Zyl Tom Bradley Amit Shankar Sander Groenendijk Gabriela Cervantes Celhay Wes Bandemer Michael Head Jordan Smith Ben Smith Andrew Escobar Navarr Barnier
Views: 3226082 CGP Grey
Proving Security Solution - 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: 3379 Udacity
What is DETERMINISTIC ENCRYPTION? What does DETERMINISTIC ENCRYPTION mean?
 
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What is DETERMINISTIC ENCRYPTION? What does DETERMINISTIC ENCRYPTION mean? DETERMINISTIC ENCRYPTION meaning - DETERMINISTIC ENCRYPTION definition - DETERMINISTIC ENCRYPTION 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 A deterministic encryption scheme (as opposed to a probabilistic encryption scheme) is a cryptosystem which always produces the same ciphertext for a given plaintext and key, even over separate executions of the encryption algorithm. Examples of deterministic encryption algorithms include RSA cryptosystem (without encryption padding), and many block ciphers when used in ECB mode or with a constant initialization vector. Deterministic encryption can leak information to an eavesdropper, who may recognize known ciphertexts. For example, when an adversary learns that a given ciphertext corresponds to some interesting message, they can learn something every time that ciphertext is transmitted. To gain information about the meaning of various ciphertexts, an adversary might perform a statistical analysis of messages transmitted over an encrypted channel, or attempt to correlate ciphertexts with observed actions (e.g., noting that a given ciphertext is always received immediately before a submarine dive). This concern is particularly serious in the case of public key cryptography, where any party can encrypt chosen messages using a public encryption key. In this case, the adversary can build a large "dictionary" of useful plaintext/ciphertext pairs, then observe the encrypted channel for matching ciphertexts. While deterministic encryption schemes can never be semantically secure, they have some advantages over probabilistic schemes. One primary motivation for the use of deterministic encryption is the efficient searching of encrypted data. Suppose a client wants to outsource a database to a possibly untrusted database service provider. If each entry is encrypted using a public-key cryptosystem, anyone can add to the database, and only the distinguished "receiver" who has the private key can decrypt the database entries. If, however, the receiver wants to search for a specific record in the database, this becomes very difficult. There are some Public Key encryption schemes that allow keyword search, however these schemes all require search time linear in the database size. If the database entries were encrypted with a deterministic scheme and sorted, then a specific field of the database could be retrieved in logarithmic time. Assuming that a deterministic encryption scheme is going to be used, it is important to understand what is the maximum level of security that can be guaranteed. A number of works have focused on this exact problem. The first work to rigorously define security for a deterministic scheme was in CRYPTO 2007. This work provided fairly strong security definitions (although weaker than semantic security), and gave constructions in the random oracle model. Two follow-up works appeared the next year in CRYPTO 2008, giving definitional equivalences and constructions without random oracles , . To counter this problem, cryptographers proposed the notion of "randomized" or probabilistic encryption. Under these schemes, a given plaintext can encrypt to one of a very large set of possible ciphertexts, chosen randomly during the encryption process. Under sufficiently strong security guarantees the attacks proposed above become infeasible, as the adversary will be unable to correlate any two encryptions of the same message, or correlate a message to its ciphertext, even given access to the public encryption key. This guarantee is known as semantic security or indistinguishability, and has several definitions depending on the assumed capabilities of the attacker.
Views: 68 The Audiopedia
Vernam Cipher Encryption and Decryption
 
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vernam cipher encryption one time pad encryption OTP encryption vernam cipher decryption one time pad decryption OTP decryption vernam cipher example in cryptography vernam cipher example in network security vernam cipher encryption and Vernam cipher decryption vernam cipher algorithm vernam cipher solved example one time pad solved example vernam cipher solution vernam cipher whiteboard teaching vernam cipher details computer and network security diploma engineering degree engineering Gujarat technological university Description This video will explain you in detail how vernam cipher encryption and decryption technique works. This video includes solved example for vernam cipher encryption and decryption algorithm on whiteboard. I had explained in detail about difficulties student might face while solving example related to vernam cipher in their examination. More videos about encryption algorithms, computer tips and tricks, ethical hacking are coming very soon so share this video with your friends. Subscribe to my youtube channel so that you can know when I upload any new video. See you all very soon in next video, have great days ahead. Thanks for watching my video. #vernam #encryption #decryption
Views: 13498 SR COMPUTER EDUCATION
Differential Cryptanalysis
 
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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: 13246 nptelhrd
cryptography - Perfect Secrecy Part II
 
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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: 1334 intrigano
Understand the Blockchain in Two Minutes
 
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Over the past decade, an alternative digital paradigm has slowly been taking shape at the edges of the internet. This new paradigm is the blockchain. After incubating through millions of Bitcoin transactions and a host of developer projects, it is now on the tips of tongues of CEOs and CTOs, startup entrepreneurs, and even governance activists. Though these stakeholders are beginning to understand the disruptive potential of blockchain technology and are experimenting with its most promising applications, few have asked a more fundamental question: What will a world driven by blockchains look like a decade from now? Learn more: http://www.iftf.org/blockchainfutureslab Contact us: http://www.iftf.org/blockchainfutureslab/contact
Rail Fence Cipher in Hindi – Complete Algorithm with Example
 
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Rail Fence Cipher in Hindi – Complete Algorithm with Example Like FB Page - https://www.facebook.com/Easy-Engineering-Classes-346838485669475/ Complete Data Structure Videos - https://www.youtube.com/playlist?list=PLV8vIYTIdSna11Vc54-abg33JtVZiiMfg Complete Java Programming Lectures - https://www.youtube.com/playlist?list=PLV8vIYTIdSnbL_fSaqiYpPh-KwNCavjIr Previous Years Solved Questions of Java - https://www.youtube.com/playlist?list=PLV8vIYTIdSnajIVnIOOJTNdLT-TqiOjUu Complete DBMS Video Lectures - https://www.youtube.com/playlist?list=PLV8vIYTIdSnYZjtUDQ5-9siMc2d8YeoB4 Previous Year Solved DBMS Questions - https://www.youtube.com/playlist?list=PLV8vIYTIdSnaPiMXU2bmuo3SWjNUykbg6 SQL Programming Tutorials - https://www.youtube.com/playlist?list=PLV8vIYTIdSnb7av5opUF2p3Xv9CLwOfbq PL-SQL Programming Tutorials - https://www.youtube.com/playlist?list=PLV8vIYTIdSnadFpRMvtA260-3-jkIDFaG Control System Complete Lectures - https://www.youtube.com/playlist?list=PLV8vIYTIdSnbvRNepz74GGafF-777qYw4
The RSA Cryptosystem
 
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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: 11021 nptelhrd
How the blockchain is changing money and business | Don Tapscott
 
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What is the blockchain? If you don't know, you should; if you do, chances are you still need some clarification on how it actually works. Don Tapscott is here to help, demystifying this world-changing, trust-building technology which, he says, represents nothing less than the second generation of the internet and holds the potential to transform money, business, government and society. TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design -- plus science, business, global issues, the arts and much more. Find closed captions and translated subtitles in many languages at http://www.ted.com/translate Follow TED news on Twitter: http://www.twitter.com/tednews Like TED on Facebook: https://www.facebook.com/TED Subscribe to our channel: http://www.youtube.com/user/TEDtalksDirector
Views: 1202797 TED
What is VIDEOGUARD? What does VIDEOGUARD mean? VIDEOGUARD meaning, definition & explanation
 
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What is VIDEOGUARD? What does VIDEOGUARD mean? VIDEOGUARD meaning - VIDEOGUARD definition - VIDEOGUARD explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. VideoGuard (sometimes referred to simply as NDS), produced by NDS, is a digital encryption system for use with conditional access television broadcasting. It is used on digital satellite television systems - some of which are operated by News Corporation, which owned about half (49%) of NDS until its sale to Cisco in 2012. Its two most widely used implementations are BSkyB's Sky in the United Kingdom and Ireland and DirecTV in the United States, the former of which launched the digital version of the system in 1998. Several other broadcasters around the world use the VideoGuard system, including DirecTV (Colombia), DirecTV (LatinAmerica), Hot (Israel), Yes (Israel), Viasat (Scandinavia), SKY Italia (Italy), Sky Brazil (Brazil), Sky Network Television (New Zealand), Foxtel (Australia), Airtel DigitalTV (India), Tata Sky & Hathway (DVB-C) (India), Astro (Malaysia), TrueVisions (Thailand), D Smart (Turkey), TotalTV (Balkan), ONO (Spain), Canadian Broadcasting Corporation (Canada), China Central Television (China), SBB (Serbia), KabelBW (Germany), Vivacom (Bulgaria), Dolce (Romania), STAR TV/Fox International Channels (Asia), Cignal Digital TV (Philippines), Aora TV (Indonesia), Telecom Italia (Italy), OTAU TV (Kazakhstan), OTE TV (Greece), Oi TV (Brazil). Since the majority of content provided by companies like BSkyB requires subscription, VideoGuard protects that content by encrypting both standard subscription channels and pay-per-view movies and events. Access flags can be downloaded to the subscriber's card either over the air (via 'hidden' data streams) or by using the box's built in modem, thereby allowing rapid changing of channel packages and ordering of events. Already in use in America since 1997, the VideoGuard system was introduced to the UK by NDS in 1998 with the launch of Sky Digital, replacing the VideoCrypt system (also supplied by NDS) in use on Sky's analogue broadcasts. Despite widespread piracy of the US DirecTV service between 1997 and 2002, the implementation in the UK remained secure until 2014 when a BBC investigation revealed that some companies in south London offered pirated Sky TV sold for L10 a month. The BBC report quoted Keith Cottenden, forensic services director at consultants Cy4or, said in February 2014 that there were some areas in the UK where those hacking satellite TV outnumber viewers paying for it legitimately. Various pay per view flaws have been identified in the past, related merely to the circuitry of the set-top box (STB), rather than the NDS card. It is suspected that the version initially used by Sky was either insecure or close to being broken, as a software update rolled out to all boxes required replacement of the BSkyB subscriber's viewing card. Even so, wholesale card replacements are rare, currently having occurred just twice during the lifetime of Sky Digital - once in 2002/2003, and again in 2009 (replacements carried out between April and June). While most commonly used to protect pay-TV, VideoGuard is also used by numerous non-subscription broadcasters to enforce geographic rights restrictions. VideoGuard has been used by the BBC, ITV, and Channel 4 to restrict non-UK viewing, although in recent years these broadcasters have moved to broadcasting FTA on the more geographically restricted footprint of the Astra 2D satellite which is mainly, although not entirely, focused on the UK and Ireland. In some cases, encryption is still used on some versions of ITV and Channel 4 services where rights issues or a lack of capacity on the Astra 2D satellite are an issue. Many broadcasters choose to pair their cards, meaning that a paired (also called "married") card can be used only in a specific broadcaster-supplied STB, or by using the serial number from said receiver with one of the reverse-engineered solutions. In the case of Sky, all cards are married to a particular STB, although almost all non-premium channels will still allow viewing even if the box and card are not paired. Other channels, such as Sky's sports and movie channels, cannot be viewed unless the viewing card is being used in its specifically paired set top box.
Views: 2763 The Audiopedia
ep 13: How is bitcoin "locked" to an address - OP_CHECKSIG, locking scripts, signatures, UTXO chain
 
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I've been meaning to make this video for a long time. It follows on from episode 12 which talks about locking and unlocking scripts and here we finish off the explanation with a look into how digital signatures are used to ensure that only the intended recipient of UTXO (unspent transaction output) can actually spend that UTXO in new transactions. Essentially the transaction is defined and then hashed and that hash is encrypted with the private key of the transaction creator (spender) - that becomes a signature of the transaction - and is used by all the nodes in the network to validate the transaction, and ensure that corresponding public key is the one used as the beneficiary of the output referenced in the transaction inputs.
Views: 3567 Matt Thomas
Theory and Practice of Cryptography
 
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Google Tech Talks November, 28 2007 Topics include: Introduction to Modern Cryptography, Using Cryptography in Practice and at Google, Proofs of Security and Security Definitions and A Special Topic in Cryptography This talk is one in a series hosted by Google University: Wednesdays, 11/28/07 - 12/19/07 from 1-2pm Speaker: Steve Weis Steve Weis received his PhD from the Cryptography and Information Security group at MIT, where he was advised by Ron Rivest. He is a member of Google's Applied Security (AppSec) team and is the technical lead for Google's internal cryptographic library, KeyMaster.
Views: 111918 GoogleTechTalks
Block Cipher Modes of Operation | CTR mode | Mode of operation of block cipher | Part 5 | Hindi Urdu
 
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#askfaizan | #syedfaizanahmad Block Cipher Modes of Operation | OFB mode https://youtu.be/F2RwmXwrdV8 Block Cipher Modes of Operation | CFB mode https://youtu.be/yF_iA7Rv7k4 Block Cipher Modes of Operation | CBC mode | Part 2 https://youtu.be/Q7LKmASkVSU Block Cipher Modes of Operation | ECB mode | Part 1 https://youtu.be/mkY5mNSnuko Hill Cipher | Complete Algorithm with Example https://youtu.be/B0Q7w7Fd7ms Playfair Substitution Cipher https://youtu.be/w_xr7pj-O6c Monoalphabetic Substitution Cipher https://youtu.be/Hw1T7GOnVW0 Caesar Cipher | Caesar Substitution Cipher https://youtu.be/2N9GlhysYJw PlayList : Cryptography and Network Security : https://www.youtube.com/playlist?list=PLhwpdymnbXz7hvvqhqjIIG4tEdhAgQqll Block cipher processes the data blocks of fixed size If size of message is larger than block size. Then, the message is divided into a series of sequential message blocks. Multiple blocks of plaintext are encrypted using the same key, security issues arise. To apply a block cipher in a variety of applications, five modes of operation have been defined by NIST 1. Electronic Code Book Mode 2. Cipher Block Chaining Mode 3. Output Feedback Mode 4. Cipher Feedback Mode 5. Counter Mode The simplest mode is the electronic codebook (ECB) mode Plaintext is handled one block at a time Each block of plaintext is encrypted using the same key The ECB mode is deterministic If plaintext block P1, P2,…, Pm are encrypted twice under the same key, the output ciphertext blocks will be the same. CBC is technique in which the same plaintext block, if repeated, produces different ciphertext blocks Each plaintext block is XORed with the ciphertext block that was previously produced To produce the first block of ciphertext, an initialization vector (IV) is XORed with the first block of plaintext For decryption, IV data is XORed with first ciphertext block decrypted. CFB is similar to CBC, it also make use of Initialization Vector. In CFB, plaintext (b bits) is divided into segments of s bits. Process s bits at a time. Common value of s is 8 bits. Cipher text block is encrypted and the output is XOR-ed with the current Plain text block to create the current Cipher text block. Each ciphertext block gets ‘fed back’ into the encryption process in order to encrypt the next plaintext block. The output feedback (OFB) mode is similar in structure to that of CFB. In CFB, the ciphertext unit is fed back to the shift register, In OFB, The output of the encryption function is fed back to the shift register. It remains localized to one single block, Affecting one plaintext block affects one ciphertext block only Complementing a bit in the ciphertext complements a bit in the plaintext. Like OFB, Counter mode turns a block cipher into a stream cipher It generates the next keystream block by encrypting successive values of a “counter”. A counter equal to the plaintext block size. The counter is initialized to some value and then incremented by 1 for each subsequent block.
Views: 5 Ask Faizan
The Third Industrial Revolution: A Radical New Sharing Economy
 
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The global economy is in crisis. The exponential exhaustion of natural resources, declining productivity, slow growth, rising unemployment, and steep inequality, forces us to rethink our economic models. Where do we go from here? In this feature-length documentary, social and economic theorist Jeremy Rifkin lays out a road map to usher in a new economic system. A Third Industrial Revolution is unfolding with the convergence of three pivotal technologies: an ultra-fast 5G communication internet, a renewable energy internet, and a driverless mobility internet, all connected to the Internet of Things embedded across society and the environment. This 21st century smart digital infrastructure is giving rise to a radical new sharing economy that is transforming the way we manage, power and move economic life. But with climate change now ravaging the planet, it needs to happen fast. Change of this magnitude requires political will and a profound ideological shift. To learn more visit: https://impact.vice.com/thethirdindustrialrevolution Click here to subscribe to VICE: http://bit.ly/Subscribe-to-VICE Check out our full video catalog: http://bit.ly/VICE-Videos Videos, daily editorial and more: http://vice.com More videos from the VICE network: https://www.fb.com/vicevideo Click here to get the best of VICE daily: http://bit.ly/1SquZ6v Like VICE on Facebook: http://fb.com/vice Follow VICE on Twitter: http://twitter.com/vice Follow us on Instagram: http://instagram.com/vice Download VICE on iOS: http://apple.co/28Vgmqz Download VICE on Android: http://bit.ly/28S8Et0
Views: 2692379 VICE
transposition netwinz
 
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netwinz TRANSPOSITION CIPHER Introduction: In cryptography, a transposition cipher is method of encryption by which the positions held by units of plaintext (which are commonly characters or groups of characters) are shifted according to a regular system, so that the cipher text constitutes a permutation of the plaintext. That is, the order of the units is changed. Mathematically a bijective function is used on the characters' positions to encrypt and an inverse function to decrypt. In a columnar transposition, the message is written out in rows of a fixed length, and then read out again column by column, and the columns are chosen in some scrambled order. Both the width of the rows and the permutation of the columns are usually defined by a keyword. For example, the word ZEBRAS is of length 6 (so the rows are of length 6), and the permutation is defined by the alphabetical order of the letters in the keyword. In this case, the order would be "6 3 2 4 1 5". In a regular columnar transposition cipher, any spare spaces are filled with nulls; in an irregular columnar transposition cipher, the spaces are left blank. Finally, the message is read off in columns, in the order specified by the keyword. HOW TO CONDUCT THE EXPERIMENT: Click on Presentation Layer on the Main Window and Then Select "TRANSPOSITION CIPHER" Module from the Modules displayed in the centre of the window. TRANSPOSITION CIPHER Window will open up as shown in SNAPSHOT-1. SNAPSHOT-1 TRANSMITTER: 1. Enter the "IP Address" of the computer to which you intend to send data. 2. Enter the Key for Encryption. The key value is between 5 digits each digit between 1 and 5. The key determines the column order for encryption. 3. Enter the Data that needs to be encrypted in the "TEXT" textbox. 4. Click on "ENCRYPT" button to encrypt the data. The table displays the columnar Cipher Table as shown in SNAPSHOT-2. The Encrypted Data is shown in the "ENCRYTED TEXT" textbox. 5. Click on the "SEND" button to send the encrypted Data to the destination IP. SNAPSHOT-2 Use Loop back Address "127.0.0.1" to send the Data to the same computer. RECEIVER: In the Receiver Window, the Encrypted Data is displayed in the "ENCRYTED TEXT" text box as soon as the data is received as shown in SNAPSHOT-3. SNAPSHOT-3 1. Enter the Key value same as entered on the server in the "KEY" textbox. 2. Click on "DECRYPT" button to decrypt the data. The Decrypted data is shown in the "TEXT" textbox on the receiver as shown in SNAPSHOT-4 And the Transposition Cipher Table is shown in the table at the bottom of the Receiver Window. SNAPSHOT-4 Transmitter and Receiver Messages are Displayed in the "Message Window" on the extreme right. Reset Button: Click On "RESET BUTTON" to reset all the controls to initial values. Click on "HELP BUTTON" to Open TRANSPOSITION CIPHER Manual. Click on "EXIT BUTTON" To Close TRANSPOSITION CIPHER Window. Copyright © 2011 Emblitz Technologies Pvt Ltd. All rights reserved. www.netwinz.com
Views: 1560 Paras Jain