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Cryptography. Fubswrjudskb. Definition: 1: secret writing 2: the encrypting and deciphering of messages in secret code or cipher 3: the science of hiding the meaning of a message. Steganography. Hiding the existence of a message.

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Fubswrjudskb

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  1. Cryptography Fubswrjudskb Definition: 1: secret writing 2: the encrypting and deciphering of messages in secret code or cipher 3: the science of hiding the meaning of a message Cryptography Introduction

  2. Steganography Hiding the existence of a message. • One of the first uses was Invisible Ink by Pliny the Elder in the 1st Century. Plant extract dries invisible but turns brown over heat. • In ancient Greece, a message encouraging revolt against Persia was written on a person’s shaved head and hair was grown to conceal the message. They could tolerate a lack of urgency which we cannot today. • The Chinese sent messages on fine silk wrapped in a small wax ball and swallowed by the messenger. • The microdot of the Cold War spy novels in which a document is photographically reduced to the size of a pinhead is still used today. Cryptography Introduction

  3. Steganography Cryptography Introduction

  4. Steganography Cryptography Introduction

  5. Cryptography in History • The Greek Spartans created an encryption device called a Scytale which hides/reveals messages by using a leather strip wound around a staff of a specific diameter. • Julius Caesar’s Cipher to Civil War Cipher Disk • Enigma machine invented in 1918 used during WWII. • Navajo code talkers. Cryptography Introduction

  6. Modern Cryptography Moving from codebooks to computer keys • Computers for Key Generation- RSA (announced August 1977). • Encrypted text message as embedded extra bytes in an electronic image. • Digital Signatures to determine who sent the message. • Digital Time stamping of documents by trusted third party. • Secure Sockets (SSL/TLS) to protect internet financial transactions. Cryptography Introduction

  7. It’s Not Just For Spies • In the James Bond movie, “For Your Eyes Only”, the spy competes with the Soviets to retrieve an encrypted communications device. • Cryptography is REAL and not fiction. It’s affordable and everyone should use it to protect their electronic information. • You don’t need James Bond’s weapons expert, “Q,” to build an encryption gadget. Encryption software is available from many vendors. Cryptography Introduction

  8. Trivia Question What group/society invented cryptanalysis, the science of unscrambling messages without knowledge of the key? Arab scholars succeeded in finding a method for breaking the monoalphabetic substitution cipher that had remained invulnerable for several centuries. How? By using frequency analysis. Most common letter used in our alphabet is e at 12.7% frequency (t = 9.1, a = 8.2, o = 7.5). Cryptography Introduction

  9. Why Use Cryptography Cryptography Introduction

  10. Encryption Protects Privacy • It’s Illegal to open someone else’s mail but it happens. • When you mail a letter do you seal the envelope? Encryption acts like a sealed secure electronic envelope. • Third party vendors such as Google, Microsoft, etc. scan your e-mails. They are also developing systems to track your behavior, location, etc. • Be aware of what you publish on social networks such as Facebook or Twitter. Does your GPS let everyone know where you are currently? • AP - Target: 40M card accounts may be breached • Organizations that carry confidential information on encrypted flash drives avoid making headlines. Cryptography Introduction

  11. Encryption is Strong If one build a machine that would recover a 56-bit DES key in one second, it would take that machine approximately 149 trillion years to crack a 128-bit AES key. The universe is believed to be less than 20 billion years old. Cryptography Introduction

  12. Prevent Unauthorized Disclosure • What do you do when you send an e-mail to the wrong person? • A company manager attempted to send an e-mail regarding issues with an employee to a peer manager but mistakenly sent it to the employee instead. • Using cryptography combined with smart access rules could have reduced the exposure the U.S. government experienced with the Wikileaks website. • A message enciphered with a public encryption key can only be deciphered by the person holding the matching private decryption key. Cryptography Introduction

  13. Other Uses • Use encryption/decryption to secure information on mobile devices such as USB flash drives, laptops and smart phones. • Authorize documents and validate authorship with digital signatures. • Allow or restrict access to facilities or specific categories of information. • Distribution of confidential information to multiple recipients via Group Keys. • Confidential instant messaging (secure sockets) • Secure message/document disposal. Cryptography Introduction

  14. Cryptography Fundamentals Cryptography Introduction

  15. Encryption • Encryption hides the meaning of a message and decryption reveals the meaning of a message. • Symmetric encryption uses a single key to hide the message and reveal the message. • Asymmetric encryption uses a pair of keys (public, private) to hide and reveal the message. Cryptography Introduction

  16. Word Document Original After Encryption Cryptography Introduction

  17. Symmetric Encryption • Uses a single key to encrypt and decrypt a message. • Symmetric algorithms include: DES, AES, Blowfish, Rijndael, etc. • Symmetric encryption is faster to compute the encrypted result than using asymmetric encryption. Cryptography Introduction

  18. Asymmetric Encryption Uses a pair of keys (public encryption key, private decryption key) to hide and reveal the message or file. • The keys are stored in a password protected file called the keystore. • The encryption key is used to protect files that typically contains confidential or sensitive information. • The decryption key is used to decipher an encrypted file. • The encryption and decryption key are uniquely matched. Cryptography Introduction

  19. Certificates • A certificate is a file designed to hold user information and the public encryption key used to encrypt files and verify digital signatures. • Certificates can be distributed to users/associates who would want to send you encrypted files as well validate the digital signatures included in received encrypted files. • Certificates provides the public key used in other Cryptographic applications such as secure sockets, etc. Cryptography Introduction

  20. Private Decryption Key • The private decryption key is used to decipher a message or file and is held in strict confidence by the owner. • The private key is used to generate a unique digital signature for any message or file. • If the private key is compromised, all encrypted data is at risk and should be recovered, re-encrypted with a re-issued public key. The originally encrypted files should be securely deleted. Cryptography Introduction

  21. Message Digest Algorithm The algorithm generates a digital fingerprint for a block of data. • The algorithm computes a fixed length cryptographic hash for a given message called the message digest. • The chance of collisions (generating the same hash for different messages) are extremely small. • Changing one bit in a message will lead to unpredictable results when generating the hash. One can easily tell if tampering had taken place. • The private decryption key is used within the algorithm to generate a unique hash number which is called the digital signature. Cryptography Introduction

  22. Digital Signatures • A unique digital signature is generated for each encrypted file using the private decryption key. • Discourages a forger from altering the message and allows the receiver to know for certain the file has not been changed after it was signed. • Authenticates who originated the message using the encryption key. Cryptography Introduction

  23. How to Use Cryptography Cryptography Introduction

  24. Step 1 – Generate Key Pair The first step in using Cryptography is for a user named Lisa to generate a pair of asymmetric encryption keys (public encryption key and private decryption key) and store them in a file called the keystore. The keystore file is password protected to prevent unauthorized access and is kept separate from encrypted files. The asymmetric encryption keys are generated in tandem and the encryption key uniquely corresponds to the decryption key. Cryptography Introduction

  25. Step 2 – Encrypt/Sign Files Lisa can immediately use the encryption key to protect any personal or confidential files and the decryption key to decipher them. The files can be of any type such as text, images, spread sheets, etc. Lisa can generate and add a unique digital signature to any of her files by applying the decryption key. The receiver can use the encryption key to validate who sent the file Cryptography Introduction

  26. Step 3 – Exchange Keys If the user, Lisa, wants to exchange secure files with another person, Jim, then Lisa gives a copy of her certificate (encryption key) to Jim so he can send her a secure message/file that only she can decipher. If Lisa wants to write to Jim securely she needs a copy of his certificate (encryption key). Cryptography Introduction

  27. Step 4 – E-Mail Secure Files Lisa uses Jim’s encryption key to encipher a file and sends it as an e-mail attachment. Additionally, Lisa creates a digital signature with her decryption key and includes it in the encrypted attachment. After Jim receives the e-mail, he authenticates the signature included with the attachment using Lisa’s encryption key. Jim deciphers the attachment using his decryption key. Cryptography Introduction

  28. Caesar Cipher Lab Now would be a good time to experiment with an actual substitution cipher. An example of Caesar Cipher is available on the web site: www.logicalanswers.com under the Education page. Cryptography Introduction

  29. DocuArmor Cryptography Introduction

  30. DocuArmor Features • Portable Security - Compact enough to fit on a USB drive and carry in your pocket. • Uses a hybrid combination of highest symmetric encryption (AES 256-bit) along with RSA asymmetric encryption to protect your information. • Exchange confidential information between other DocuArmor licensed users. • Uses digital signatures to validate who sent a message or file. • Secure deletion prevents hackers from recovering information from your disk. • Easy to use and password protected. Cryptography Introduction

  31. Initializing DocuArmor Information is collected in order to generate a pair of encryption keys during initialization of the DocuArmor application. Cryptography Introduction

  32. Critical DocuArmor Files After the encryption keys are generated you should store the backup copies in a safe location. Cryptography Introduction

  33. Starting DocuArmor Just enter your password and DocuArmor is ready to be used. Cryptography Introduction

  34. Using DocuArmor Drag and drop files into the vault and they will be encrypted. Cryptography Introduction

  35. References • Hook, David. Beginning Cryptography with Java. Wrox Press. ISBN: 0-7645-9633-0. August 2005. 448 pages. • Horstman, Cay and Cornell, Gary. Core Java 2 Volume II-Advanced Features. Sun Microsystems Press. ISBN: 0-13-092738-4. 2002. 1024 pages. • Singh, Simon. The Code Book. Doubleday ISBN: 0-38-549531-5. September 14, 1999. 416 pages. Cryptography Introduction

  36. Contact Information Logical Answers Inc. 491 Leetonia Ave Troy, Michigan 48085-5518 (248) 528-4498 www.LogicalAnswers.com sales@logicalanswers.com We offer custom programming and technology consulting services. Our DocuArmor suite of cryptographic products are for sale offering encryption and secure socket communications. Cryptography Introduction

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