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Found 10 results

  1. https://www.math.auckland.ac.nz/~sgal018/crypto-book/crypto-book.html Direct link: https://www.math.auckland.ac.nz/~sgal018/crypto-book/main.pdf Via:
  2. Security in computer science is a huge point every individual and company. Communications (either between humans or human-network or whichever online communication) are susceptible to be sniffed or manipulated. For example, using http instead of https is insecure (sometimes even tagged by your browser as untrustful) as information that goes through it is not encrypted and someone is able to impersonate your accounts with the collected data. This is why https everywhere and privacy badger are recommended for secure browsing. But when we say "encrypt", what are we referring to? Back in the days when computers weren't a thing, cryptography already existed. Maths has always been there to protect our communications. Sometimes it was a letter, sometimes it was a note or a messenger, but there were tons of witty ways of hiding messages. For example, the "monoalphabetic substitution system" is a bijective application e: A -> A Being A an alphabet an A* the chain aggregation over A with arbitrary length: e: A* -> A*, [e(X0 X1 ...) = e(X0) e(X1)...] An example of this is the Cesar cipher. This consist on cyclic displacement to the right, mathematically (with displacement = +3): e: Z23 -> Z23, [e(x) = x+3 (mod 23)] Note it's Z23 because Roman alphabet length = 23. Unfortunately this method (that you might have used as a kid to pass notes) has a huge security hole: letters Periodicity Analysis. Let me explain myself. Every language has an already study that shows the periodicity a letter appears in such language. Even if the letters are mixed, if we take this numbers (in English, for example, most used letters are E or T) we can guess the message. There's a similar cipher version called "Polyalphabetic substitution system". This system uses a keyword to cipher all the message. (It's like repeating monoalphabetic many times). Let me show you an example: our keyword is TUX and our message is HELP ME OBI WAN KENOBI We have our alphabet tagged with numbers, like this: A B C ... X Y Z 1 2 3 ... 23 24 25 So TUX is equal to 19,20,23 And HELP ME OBI WAN KENOBI is equal to 7,4,11,15,12,4,14,1,8,22,0,13,10,4,13,14,1,8 Now we set the numbers in TUX in the message, like this: H E L P M E O B I W A N K E N O B I T U X T U X T U X T U X T U X T U X 19 20 23 19 20 23 19 20 23 19 20 23 19 20 23 19 20 23 And now we add the value setted to the original value (in mod 25). H E ... B I 7 + 19 4 + 20 ... 1 + 20 8 + 23 A Y ... V F And so HELPMEOBIWANKENOBI = AYIIGBHVFPUKDYKHVF This system is a little bit more complex but also vulnerable to periodicity analysis if we know the keyword length. We also have Hill cipher, which consist in matrix cipher. For example, we can cipher the word MATH, using the key matrix = ([32],[15]) M,A = ([12],[0]) in the alphabet T,H = ([10],[7]) ([32],[15])([12],[0]) = ([0],[12]) ([32],[15])([10],[7]) = ([71],[54]) = ([35][18]) **in mod 36 (alphanumeric)** So MATH = AM95 This system is way more secure than the others. There's also the so called transposition systems in which consist in changing the letters order (the periodicity analysis also fails here). For example: This lasts were very used in the WW2, alongside One-time-pad and notebooks ciphers. In general, there are certain rules a cryptosystem must follow. For example, the secret must be hidden with the algorithm and the power of this algorithm is in it's form, not the way the algorithm is hidden to the public. (This is the main problem some users have with privative cryptography). Most of the mathematical rules can be found in Communication theory of secrecy systems , a study by C.E. Shannon about the matter. Current ciphering works in bits, not letters, and latests cryptography studies are developing quantum cryptography, for the upcoming of quantum computers. This could mean a complete chaos for regular computer cryptography, and we shall be on guard! On the mean time we can keep writing love notes and letter in basic cryptography. It is said that it worked with Don Juan , who made a woman fall in love with him after he deciphers a message she cipher with Vigenere. Sursa: https://dev.to/terceranexus6/fun-with-secrets-2p3
  3. A number of them voiced their distrust in emails to one another, seen by Reuters, and in written comments that are part of the process. The suspicions stem largely from internal NSA documents disclosed by Snowden that showed the agency had previously plotted to manipulate standards and promote technology it could penetrate. Budget documents, for example, sought funding to "insert vulnerabilities into commercial encryption systems." More than a dozen of the experts involved in the approval process for Simon and Speck feared that if the NSA was able to crack the encryption techniques, it would gain a "back door" into coded transmissions, according to the interviews and emails and other documents seen by Reuters. "I don't trust the designers," Israeli delegate Orr Dunkelman, a computer science professor at the University of Haifa, told Reuters, citing Snowden's papers. "There are quite a lot of people in NSA who think their job is to subvert standards. My job is to secure standards." sursa: http://mobile.reuters.com/article/amp/idUSKCN1BW0GV via : https://www.schneier.com/blog/archives/2017/09/iso_rejects_nsa.html#comments
  4. In this course, you will learn all of the old and modern security systems that have been used and are currently being used. You also learn how to crack each one and understand why certain security systems are weak and why others are strong. We will even go into RSA, AES and ECC which are the three main modern cryptosystems used today. Learn How to Crack the Code! Advanced Encryption Standard Public Key Cryptosystems (ie RSA) Elliptic Curve Cryptography Modern Cryptographic Security Advanced Mathematical Techniques Master the Art of Security! Security is a very important tool, and the ability to use mathematics to hide information is vital to the world. See how our banks and even the National Security Agency (NSA) keeps their data secure. With the knowledge of this course, you can even apply for security jobs at places like the NSA! This is a course that is rarely taught in Universities, so take advantage and start today! Most of today's security is based upon RSA, and AES but the NSA is trying to push Elliptic Curve Cryptography since it is more secure than RSA. In this course, we learn all of these cryptosystems and their weaknesses. We give examples of every cipher that we cover. Only a small number of people currently understand these systems, and you can join them. The best part of this course is the fun in breaking the codes. We offer many examples of each cryptosystem and how to break each one. Even as you are reading this, your https:// at the top says that the RSA Algorithm is successfully keeping your information from flooding the internet. You can find out how it all works and the mathematical structures that keep it secure in this course. So what are you waiting for? Who is the target audience? Anyone interested in computers and security Anyone who wants to work at the National Security Agency Anyone who understands a little about mathematics Anyone who wants to understand why certain systems are secure Download: magnet:?xt=urn:btih:303714e54be3a7d973b7c20b31225366de667026&dn=Cryptography%20And%20Math%20Security%20Crack%20The%20Code pass:"www.descargasnsn.com" Sursa: http://certcollection.org/forum/topic/311373-udemy-cryptography-and-math-security-crack-the-code-torrent/
  5. Usr6

    Crypto 101

    An introduction to applied cryptography and information security suitable for programmers of all ages and skill levels.
  6. What is Cryptography? Cryptography is the science of study of secret writing. It helps in encrypting a plain text message to make it unreadable. It is a very ancient art; the root of its origin dates back to when Egyptian scribes used non-standard hieroglyphs in an inscription. Today, electronic or Internet communication has become more prevalent and a vital part of our everyday life. Securing data at rest and data in transit has been a challenge for organizations. Cryptography plays a very important role in the CIA triad of Confidentiality, Integrity and Availability. It provides mathematical techniques related to aspects of information security such as confidentiality, data integrity, entity authentication, and data origin authentication. Over the ages, these techniques have evolved tremendously with technological advancements and growing computing power. Encryption is a component in cryptography or science of secret communication. The part “en” means “to make” and “crypt” means hidden or secret. Encryption can be defined as a process to make information hidden or secret. In this digital age, encryption is based on two major algorithm. Asymmetric or Public key cryptography: Uses two keys, one is a public encryption key and other is a private decryption key. Symmetric or Secret key cryptography: Uses the same key for encryption and decryption processes. Challenges in traditional cryptography The keys used in modern cryptography are so large, in fact, that a billion computers working in conjunction with each processing a billion calculations per second would still take a trillion years to definitively crack a key. Though this doesn’t seem to be a problem now, it soon will be. Quantum computers are going to replace traditional binary computing in the near future. Since they can operate on the quantum level, these computers are expected to be able to perform calculations and operate at speeds no computer in use now could possibly achieve. So the codes that would take a trillion years to break could possibly be cracked in much less time with quantum computers. Traditional cryptography has the problem of key distribution and eavesdropping. Information security expert Rick Smith points out that the secrecy or strength of a cipher ultimately rests on three major things: The infrastructure it runs in: If the cryptography is implemented primarily in software, then the infrastructure will be the weakest link. If Bob and Alice are trying to keep their messages secret, Tom’s best bet is to hack into one of their computers and steal the messages before they’re encrypted. It’s always going to be easier to hack into a system, or infect it with a virus, than to crack a large secret key. In many cases, the easiest way to uncover a secret key might be to eavesdrop on the user and intercept the secret key when it’s passed to the encryption program. Key size: In cryptography, key size matters. If an attacker can’t install a keystroke monitor, then the best way to crack the ciphertext is to try to guess the key through a “brute-force” trial-and-error search. A practical cipher must use a key size that makes brute-force searching impractical. However, since computers get faster every year, the size of a “borderline safe” key keeps growing. Algorithm quality: Cipher flaws can yield “shortcuts” that allow attackers to skip large blocks of keys while doing their trial-and-error search. For example, the well-known compression utility PKZIP traditionally incorporated a custom-built encryption feature that used a 64-bit key. In theory, it should take 264 trials to check all possible keys. In fact, there is a shortcut attack against PKZIP encryption that only requires 227 trials to crack the ciphertext. The only way to find such flaws is to actually try to crack the algorithm, usually by using tricks that have worked against other ciphers. An algorithm usually only shows its quality after being subjected to such analyses and attacks. Even so, the failure to find a flaw today doesn’t guarantee that someone won’t find one eventually. At present, RSA Key length of 2048 bits is considered “Acceptable”. In 2009, researchers were able to crack a 768-bit RSA key and it remains as the current factoring record for the largest general integer. The Lenstra group estimated that factoring a 1024-bit RSA modulus would be about 1,000 times harder than their record effort with the 768-bit modulus, or in other words, on the same hardware, with the same conditions, it would take about 1,000 times as long. Breaking a 2048 bit key would take about 4.3 billion times longer than doing it for a 1024-bit key. A symmetric key algorithm DES is considered to be insecure now since the 56-bit key size it used was too small. Although DES uses a block size of 64-bit, only 56 bits are actually used by the algorithm; the final 8 bits are used for the parity check. In simple words, traditional cryptography and its security are based on difficult mathematical problems which are mature both in theory and realization. Both the secret-key and public-key methods of cryptology have unique flaws. With growth of computing power, the strength of traditional cryptography might become weak and breakable. DNA Computing A new technique for securing data using the biological structure of DNA is called DNA Computing (A.K.A molecular computing or biological computing). It was invented by Leonard Max Adleman in the year 1994 for solving the complex problems such as the directed Hamilton path problem and the NP-complete problem similar to The Traveling Salesman problem. Adleman is also known as the ‘A’ in the RSA algorithm – an algorithm that in some circles has become the de facto standard for industrial-strength encryption of data sent over the Web. The technique later on was extended by various researchers for encrypting and reducing the storage size of data that made the data transmission over the network faster and secured. DNA can be used to store and transmit data. The concept of using DNA computing in the fields of cryptography and steganography has been identified as a possible technology that may bring forward a new hope for unbreakable algorithms. Strands of DNA are long polymers of millions of linked nucleotides. These nucleotides consist of one of four nitrogen bases, a five carbon sugar and a phosphate group. The nucleotides that make up these polymers are named after the nitrogen base that it consists of: Adenine (A), Cytosine ©, Guanine (G) and Thymine (T). Mathematically, this means we can utilize this 4 letter alphabet ? = {A, G, C, T} to encode information, which is more than enough considering that an electronic computer needs only two digits, 1 and 0, for the same purpose. Advantages of DNA computing Speed – Conventional computers can perform approximately 100 MIPS (millions of instruction per second). Combining DNA strands as demonstrated by Adleman made computations equivalent to 10^9 or better, arguably over 100 times faster than the fastest computer. Minimal Storage Requirements – DNA stores memory at a density of about 1 bit per cubic nanometer, where conventional storage media requires 10^12 cubic nanometers to store 1 bit. Minimal Power Requirements – There is no power required for DNA computing while the computation is taking place. The chemical bonds that are the building blocks of DNA happen without any outside power source. There is no comparison to the power requirements of conventional computers. Multiple DNA crypto algorithms have been researched and published, like the Symmetric and Asymmetric Key Crypto System using DNA, DNA Steganography Systems, Triple Stage DNA Cryptography, Encryption algorithms inspired by DNA, and Chaotic computing. DNA Cryptography can be defined as a technique of hiding data in terms of DNA sequence. In the cryptographic technique, each letter of the alphabet is converted into a different combination of the four bases which make up the human deoxyribonucleic acid (DNA). DNA cryptography is a rapid emerging technology which works on concepts of DNA computing. DNA stores a massive amount of information inside the tiny nuclei of living cells. It encodes all the instructions needed to make every living creature on earth. The main advantages of DNA computation are miniaturization and parallelism of conventional silicon-based machines. For example, a square centimeter of silicon can currently support around a million transistors, whereas current manipulation techniques can handle to the order of 1020 strands of DNA. DNA, with its unique data structure and ability to perform many parallel operations, allows one to look at a computational problem from a different point of view. A simple mechanism of transmitting two related messages by hiding the message is not enough to prevent an attacker from breaking the code. DNA Cryptography can have special advantage for secure data storage, authentication, digital signatures, steganography, and so on. DNA can also be used for producing identification cards and tickets. “Trying to build security that will last 20 to 30 years for a defense program is very, very challenging,” says Benjamin Jun, vice president and chief technology officer at Cryptography Research. Multiple studies have been carried out on a variety of biomolecular methods for encrypting and decrypting data that is stored as a DNA. With the right kind of setup, it has the potential to solve huge mathematical problems. It’s hardly surprising then, that DNA computing represents a serious threat to various powerful encryption schemes. Various groups have suggested using the sequence of nucleotides in DNA (A for 00, C for 01, G for 10, T for 11) for just this purpose. One idea is to not even bother encrypting the information but simply burying it in the DNA so it is well hidden, a technique called DNA steganography. DNA Storage of Data has a wide range of capacity: Medium of Ultra-compact Information storage: Very large amounts of data that can be stored in compact volume A gram of DNA contains 1021 DNA bases = 108 Terabytes of data. A few grams of DNA may hold all data stored in the world. Conclusion DNA cryptography is in its infancy. Only in the last few years has work in DNA computing seen real progress. DNA cryptography is even less well studied, but ramped up work in cryptography over the past several years has laid good groundwork for applying DNA methodologies to cryptography and steganography. Researches and studies are being carried out to identify a better and unbreakable cryptographic standard. A number of schemes have been proposed that offer some level of DNA cryptography, and are being explored. At present, work in DNA cryptography is centered on using DNA sequences to encode binary data in some form or another. Though the field is extremely complex and current work is still in the developmental stages, there is a lot of hope that DNA computing will act as a good technique for Information Security. References An Overview of Cryptography Handbook of Applied Cryptography Encryption vs. Cryptography - What is the Difference? Traditional Cryptology Problems - HowStuffWorks Understanding encryption and cryptography basics https://www.digicert.com/TimeTravel/math.htm http://securityaffairs.co/wordpress/33879/security/dna-cryptography.html http://research.ijcaonline.org/volume98/number16/pxc3897733.pdf http://searchsecurity.techtarget.com/answer/How-does-DNA-cryptography-relate-to-company-information-security http://www.technologyreview.com/view/412610/the-emerging-science-of-dna-cryptography/ Source
  7. Introduction In this mini-course, we will learn about various aspects of cryptography. We’ll start with cryptography objectives, the need for it, various types of cryptography, PKI, and we’ll look at some practical usage in our daily digital communication. In this mini-course, I will explain every detail with an example which end users can perform on their machines. What is cryptography and why it is required? Today, digital communication has become far more important than what it was a decade ago. We use internet banking, social networking sites, online shopping, and online business activities. Everything is online these days, but the internet is not the most secure means to conduct all those activities. Nobody would want to do an online transaction with communication from their machine to their bank through an open channel. With cryptography, the channel secured between different entities which helps to do business activity in a more secure fashion. Cryptography is a method of storing and transmitting data in a particular form so that only those for whom it is intended can read it. Cryptography is a broad term which includes sub disciplines and very important concepts such as encryption. Let’s get into the main objectives of cryptography. Cryptography Objectives C-Confidentiality: Ensuring the information exchanged between two parties is confidential between them and is not visible to anyone else. I-Integrity: Ensuring that message integrity is not changed while in transit. A-Availability: Ensuring systems are available to fulfill requests all the time. Here are some additional concepts: Authentication: To confirm someone’s identity with the supplied parameters, such as usernames, passwords, and biometrics. Authorization: The process to grant access to a resource to the confirmed identity based on their permissions. Non-Repudiation: To make sure that only the intended endpoints have sent the message and later cannot deny it. Cryptography key definitions Here’s some cryptographic key terminology: Plaintext: The original raw text document onto which encryption needs to be applied. Ciphertext: When we apply encryption to a plaintext document, the output is ciphertext. Encryption: Encryption is the process of converting plaintext to ciphertext using an encryption algorithm. We have different types of encryption available today like symmetric, asymmetric and hybrid encryption. We will discuss them in depth later in the course. Encryption algorithm: An encryption algorithm is a mathematical procedure for converting plaintext into ciphertext with a key. Various examples of encryption algorithms include RSA, AES, DES, and 3DES. Key-length: Choosing an encryption algorithm with an appropriate keysize is an important decision to make. The strength of the key is usually determined by keysize, or the number of bits. Thus, the larger the bit size of a key, the more difficult it is to break the key. For example, with a key which has a bit length of 5, the key will have only 2^5 or 32 combinations. That’s pretty easy to break considering today’s computation methods. That’s why older algorithms like WEP (40 bits) & DES (56 bits) are considered obsolete and now much more powerful algorithms with larger key sizes, such as AES (128 bits), are now used. Hash: A hash value, also called a message digest, is a number generated from a string of text. As per the hash definition, no two different texts should produce the same hash value. If an algorithm can produce the same hash for a different string of text, then that algorithm is not collision free and can be cracked. Various examples of hash algorithm are MD2, MD5 and SHA-1 etc. Digital signature: Digital signature is the process of making sure that the two entities talking with each other can establish a trust relationship among them. We will take a look at its practical demonstration later in this document. Source Part2 Part3 Part4 Part5
  8. “Quantum cryptography uses photons and physics to generate cryptographic keys” What is quantum cryptography? Quantum cryptography is NOT a new algorithm to encrypt and decrypt data. Rather it is a technique of using photons to generate a cryptographic key and transmit it to a receiver using a suitable communication channel. A cryptographic key plays the most important role in cryptography; it is used to encrypt/decrypt data. Types of cryptography There are two types of cryptography: Symmetric Cryptography Asymmetric Cryptography Symmetric Key Cryptography is also known as Secret Key Cryptography (SKC) where a key (any text, numbers, etc.) is used to encrypt data, and the same key is used to decrypt that data. The smallest change in the secret key will fail to decrypt an encrypted message. For example, text that is encrypted using AES encryption with key Infosec will fail to decrypt another cipher text which was encrypted using key INFOSEC. Asymmetric Key Cryptography is also known as Public Key Cryptography (PKC) where two sets of keys are generated. One is called a public key and other is called a private key. A public key is used to encrypt data whereas a private key is used to decrypt that data. Similar to symmetric cryptography, the smallest change in any of the two keys will make them useless to get the original data. A benefit of asymmetric cryptography is that you can share the public key with the whole world so that they can use it to send you encrypted data. And the private key is stored safely with the owner and is used for decryption. One disadvantage of this type of cryptography is that if your private key is lost or leaked then you will have to generate a new pair of public and private keys. Why do we need quantum cryptography? Every new solution is made because of some problem we have with the current solution. The case is no different with this one. Let us see the problem first. The problem with symmetric cryptography is that the same key is used to both encrypt and decrypt the messages. If for some reason that key is leaked to some third party, then it can be used to decrypt communication between two trusted devices or persons. In the worst case, the communication can be intercepted and altered. Today’s huge computing power (these days even Xbox and PlayStation at homes have huge power) can be used to crack a key used in symmetric cryptography. Another major problem with this type of cryptography is how to decide which key to use and how to share between trusted devices or persons. Imagine a key has to be shared between India and America, then that communication too has to be secured before sharing the key. Coming to the problem of asymmetric cryptography, it is not something we are facing right now, but seeing the pace of changing technology, we will be facing it soon. Most of the keys used in public key cryptography are at least 128-bit keys which are considered to be very strong. An attacker can easily get hold of the public key because it is shared by the user. But to generate a private key for that public key involves huge amounts of calculations with permutations and combinations. At present a supercomputer is what you need to crack a PKC and many years to complete it. But it will become pretty much possible with the use of quantum computers which use quantum physics to operate and have very high efficiency and computation speed. A quantum computer is a theoretical concept right now and will utilize atoms and molecules to perform computing at a very high speed. According to Moore’s Law, in an integrated circuit the number of transistors doubles every 2 years. It means that the speed of computing will increase to a very high level every two years. Right now Intel i7 processor integrated circuit has 1.4 billion transistors. Clearly, in the coming decades computing speed will increase and the age of quantum computers will become a reality. Now from our above discussion it is very clear that the biggest problem with the current cryptographic techniques is keys and their security in transmission. How does quantum cryptography work? In quantum cryptography, the source sends a key to the receiver, and this key can be used to decrypt any future messages that are to be sent. When the key has been successfully sent and received, the next step is to send encrypted data to the receiver and let it decrypt and process that data. Important: the key is the main part of cryptography and should be sent in a very secure manner. Quantum cryptography has a different way of sending the key to the receiver. It uses photons to send a key. What is a photon, and how it is used? A photon is the smallest particle of light. It has three types of spins: Horizontal Vertical Diagonal (Right and Left) A photon has the capability to spin in all three states at the same time. How do we use it in cryptography? Another part of physics and photons is polarization. Polarization can be used to polarize (pass through a filter) a photon so that it has a particular spin, vertical or horizontal or diagonal. Polarization of a photon is performed using polarization filters. Now comes Heisenberg’s Uncertainty Principle, which states that it is impossible to measure together the speed and position of a particle with highest accuracy, and its state will change when measured. In other words, if an eavesdropper intercepts the transmitted photons and passes it through its polarizer, if it is wrong it will make the receiver get the wrong photon. Hence the interception of communication will get detected. It means that if a photon is polarized using say X filter (Diagonal Polarization), then to get the original spin of the photon only X filter can be used. If a + filter (Rectilinear Polarization) is used on the photon, then it will either be absorbed by the filter or the polarized photon, will be of different spin than the original photon. For example, a horizontal spinning photon when passed through a wrong filter will lead to diagonal spin, which is incorrect. The below table shows output spin for used polarization: Polarization Output Spin Rectilinear Polarization (+) Horizontal Spin (–) Vertical Spin (|) Diagonal Polarization (X) Left Diagonal Spin () Right Diagonal Spin (/) How to send data using photons One of the major concerns before using quantum cryptography is how to associate data with photons. This problem can be easily solved by assigning the spin of every photon as 0 or 1. Please see the sample table below: Spin Horizontal Spin (–) Vertical Spin (|) Left Diagonal Spin () Right Diagonal Spin (/) Value 0 1 0 1 magine Alice applies polarizations on photons and gets the spin and keeps a note of it. Every spin has a value associated with it. Please refer to the table below: Do note that Alice is able to find the spin of photon after polarization using four detectors (horizontal, vertical, right diagonal, left diagonal). Now the key in binary format is: 0101100110101011 This binary data can be converted into other formats like string and integer, depending upon choice of the users involved in the communication. Let us assume Alice wants the key to be in integer format, so the key will be: In real world implementation, the key should not be this short in length. How to share and verify the key In the above section, Alice applied polarization and calculated the value of the key, which will be transmitted to Bob. Note that transmission of these photons takes place in optical fiber cables. Alice sends the polarized photons to Bob using a suitable communication channel. Bob is listening for incoming photons and randomly applies any polarization (rectilinear or diagonal) and keeps a note of applied polarization, spin and its value. Now when the transmission has completed, Alice and Bob communicate on a public channel which needs not be encrypted. Bob tells Alice only the polarizations (not the spin or value) he applied in the exactly same sequence, and Alice only says YES/NO. This communication will be something like this: In the above communication, Bob gets to know the wrong polarizations. But do note that we have a problem here which is highlighted in orange color. See that Alice said polarization applied is wrong but the spin Bob received had the same bit value (1) as Alice’s. But Bob has no way to find what value Alice has so he has no other way but to discard his results for wrong polarization. After successful key transmission and fixing of wrong polarization, encrypted data can be sent and decrypted when received. Communication interception If a user is intercepting the communication between sender and receiver, then he will have to randomly apply polarization on the photons sent. After polarization, he will forward it to the original sender. But it is impossible for the eavesdropper to guess all polarizations correctly. So when Bob and Alice validate the polarizations, and Bob fails to decrypt the data, then the interception of communication will get detected. Conclusion Privacy and data security is right now of utmost importance to people. With quantum cryptography, secure transmission of data is possible, and chances of it being intercepted and altered are very low. This technology has been implemented in some areas. But is still under deeper research before being widely implemented. Reference: How Quantum Cryptology Works - HowStuffWorks Source
  9. OpenSSL is a robust, fully featured Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols with full-strength cryptography world-wide. Changes: Build fixes for the Windows and OpenVMS platforms. Download
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