# PowerPoint Presentation

#### Key Management and Distribution – t U

#### Chapter 10 Asymmetric-Key Cryptography

How the Public key can be trusted, that GnuPG Create Key pair, handle questions, the key Thunderbird? 3 Check the asymmetric cryptography Asymmetric Public-Key Secret-Key assessment 4 How the Public key can trusted authority infrastructure Public Key infrastructure (PKI) Financial transaction Cross-certification company, the Web-of-Trust, GnuPG will Check. You generate a symmetric key, i.e., the session-key. MD5 and SHA-1 were the most widely used hash algorithms, but are now considered to be weak and is replaced by SHA-224, SHA-256, SHA-384 or SHA-512, sometimes referred to as SHA-2. Symmetric Alice encrypts her message to Bob with KA and sends it to Trent Trent decrypts the message with KA Trent takes the decrypted message and a statement that he received this message from Alice and encrypts the entire package with KB Trent sends the encrypted bundle to Bob Bob decrypts the package with the KB. In addition to the awareness-raising it is important that both parties have installed, the PGP-compatible programs to be able to exchange PGP messages (Benz, 2001). Symmetrically Encrypting the content with a session key Using an asymmetric public key to encrypt the session key. With over 30,000 presentation design templates to choose from, crystal graphics offers more professionally-designed s and templates with stylish backgrounds and designer layouts than anyone else in the world.. A similar system was used by the British banks for Electronic Funds Transfer (EFT) Point Of Sales (POS). This interdependence provides a number of different functions, the most important guarantee probably the digital signatures that are used, among other things, that a message was generated by a particular Person, or to authenticate remote systems or users

### Symmetric and asymmetric key – SlideShare

A good hash algorithm should make it impossible to either a first input that produces a specific hash value, or allow you to calculate the original input from the hash value. Rapid development of network technology and the expansion of the information around the world, the security of information must be consistent with efficiency in the processing of hybrid approaches require.. We know it is relatively prime to either p or q, since both are Prime numbers. OF the used a 64-bit key, and many attacks have been recorded in the literature against them, and caused the need to propose, 3DES (Triple DES). It consists of three block ciphers, AES-128, AES-192 and AES-256, each of which is considered sufficient to protect government classified information up to the SECRET level with TOP SECRET information, the lengths of either 192 or 256 key. All for free. Most of the presentations and slideshows on PowerShow.com are free-to-view, many are even free to download. (Math is a bit more complicated, but not difficult going through the equations.) Slide21 The security of RSA Public-knowledge: ( e,n ) How hard it is to get d…. Our new crystal graphics Chart and diagram slides for PowerPoint is a collection of over 1000 impressively designed data-driven chart and editable diagram s guaranteed to impress any audience. In addition, NIST published the Digital Signature Standard (DSS) in 1991 for the generation of digital signatures. On the other hand, Kaliski (2003) is of the opinion that a 1024-bit RSA key can be broken in a year, that a 2048-bit RSA public key is secure enough for a PGP setup that also includes the AES and SHA-1 algorithm. (You can choose whether you allow people to download your original PowerPoint presentations and photo slideshows for a fee or free or not at all.) Check-out PowerShow.com today – FREE of charge. The recipient can view the mail of the mail to decrypt with the associated private or public key (Simmons, 1993)

### PowerPoint Presentation

This is the symmetric encryption, and it is comparatively quickly and compared to other types of encryption, such as asymmetric encryption. Goals of the hash function: Easy to calculate, Computationally difficult to calculate an input text to generate would be any given hash output, it is Extremely unlikely that two different messages would give the same hash, in Essence, these are deterministic functions, the kind of behavior happens to be Slide26 Hashing standards NIST also had a call to standardize modern hashes, 2007 results: 3 different algorithms-SHA (with a number at the end) is SHA-256, uses a compression function with inputs of size 512 bits, and outputs 256 bits, SHA-512 1024 takes and outputs 512 MD5 is sometimes used, but is generally Known to be insecure to attack, where, given two messages, one can calculate that two suffixes, so that you collide the result: calculate (for example) various PDF-files with the same hash Slide27 Takeaway message As a programmer or a user of cryptography, you should know the big packages. Process, Calculate the digest (hash value) of the content, Encrypt the hash value with the private key to create a digital signature to Send the content and the digital signature to the recipient, the recipient calculates the hash value of the message with the same hash algorithm as the sender. One of the most common asymmetric encryption method and the Diffie-Hellman key exchange, allows two parties to exchange cryptographic keys in a secure manner, regardless of whether the communication channel is private or public. However, Brute-Force attack was the only effective unlocking mechanism against it, all of the sign combinations. Therefore, performance and key distribution are improved by the combination of the two approaches, without compromising safety. 1000 X slower than the symmetric encryption.. It is primarily used for signing, encrypting E-Mails, files, text, and everything else in E-Mail communication (Zimmermann, 1995). GnuPG provides encryption and decryption services based on a series of symmetric and asymmetric algorithms (Garloff and Jaeger, 2000). To create a key-and IV-modes enter the granularity of the message, Electronic Code Book (ECB) divides the data into fixed-block-size Cipher Block Chaining (CBC) each block size is suitable XORed and encrypted in Cipher Feedback model (CFB) for encrypting a single bit or byte-Padding-no padding-PKCS7-blank bytes will be filled with a value equal to the number of bytes that are required zeros is zero-padded 2.net SYMMETRIC ENCRYPTION DESCrpytoServiceProvider OF the 56-bit triple-des, 3 X 356 keys TripleDESCrpytoServiceProvider symmetric algorithm, Rijndael-Variable(1-2,048) Rijndael managed-RC2-128-, 192-, 256 – RC2CryptoServiceProvider 3 ASYMMETRIC ENCRYPTION, Public-and Private-key-generation. How the Public key can be trusted, 5 Public Key infrastructure is used, Often in combination with Hardware-Review. If the circuit is in block encryption mode-it starts with the IDEA cipher process.The IDEA cipher applies to the 128-bit key for the block encryption. Each 16-bit-modular additions and multiplications, the Simulation of the integer calculations used in RSA. This approach tested devices and other mobile platforms, with simple text, but not with E-Mail attachments, or the communication between the Android. of The recipient the message is decrypted with the decrypted session key. 6 HASHING is concerned with the consistency of the data, i.e., integrity. A one-way computed cryptographic hash of the message, i.e., message digest, Message digest, one-way, fixed length, unique, and relatively small. RSA is used in websites, smart-cards, at the OS level, and in many other place main reasons: speed, cost, and problems with contaminated sites, etc