Electronic signature _ digital signature by NovakovaOksana


the presentation about encryption and decryption, electronic signature, digital signature, authentication, private key, public key, hashing algorithms, credit cards, online banking, smart cards.

More Info
									Electronic signature &
electronic paymant
         Universität Heidelberg
         Fachübersetzen im Kontext
         europäischer Normen
         Dozent: Dr. John Stewart
         Referentin: Oksana Novakova
         WS 2009/2010

              Encryption and decryption
              Electronic signature
              Digital signature
              Authentication
              Private key
              Public key
              Hashing algorithms
              Credit cards
              Online banking
              Smart cards

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             Sensitive information

              Credit-card information
              Social security numbers
              Private correspondence
              Personal details
              Sensitive company information
              Bank-account information

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             Encryption and Decryption

              Encryption is the method of disguising
               plaintext in such a way as to hide its

              Decryption is the process of reverting
               ciphertext in its original plaintext

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             Encryption and Decryption

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             Electronic signature

              Is defined as an electronic sound,
               symbol or process attached to or
               logically associated with a record, and
               executed or adopted by a person with
               the intent to sign the record.

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             Digital signature

              Is a way to ensure that an electronic
               document is authentic

              Rely on certain types of encryption to
               ensure authentication

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              Electronic signature insecure way of signing
              Are vulnerable to copying and tempering,
               making forgery easy

              Digital signature is legally binding > secure
              Based on PKI (Public Key Infrastructure) and is
               the result of a cryptographic operation that
               guarantees signer authenticity
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             How does it work
              You copy-and-paste the contract
              Using the special software, you obtain a message hash
               (mathematical summary) of the contract
              You then use a private key that you previously obtained
               from a public-private-key authority to encrypt the hash
              The encrypted hash becomes your digital signature of the

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             How does it work

             At the other end

              To make sure it is intact and from you, the recipient
                makes a hash of the received message

              The recipient then uses your public key to decrypt the
                message hash or summery

              If the hashes match, the received message is valid

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             Digital signature

              http://www.arx.com/flash/Digital-

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             Is used to verify that the information comes
                from a trusted source
              ways of authentication:
              Password
              Digital signatures
              Private key encryption
              Public key encryption
              Hash value
              Digital certificate

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             Private key encryption

              Is the secret key of the computer

              Encrypts the information

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             Public key encryption

              The combination of a private key and a
               public key

              Decodes the encrypted message

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             Hashing algorithm

              Hashing is the transformation of a
               string of characters into a usually
               shorter fixed-length value or key that
               represents the original string.

              the public key encryption is based on
               a hash value

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              Hashing algorithm

              The value is computed from a base input
             number using a hashing algorithm

              Input number     Hashing       Hash value
                 10,667      Input # x 143   1,525,381

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             Digital certificate

              Serves for the secure Web server

              The information that says the Web
               server is trusted by an independent
               source known as a Certificate Authority

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             Credit cards

              Origin USA during 1920

              Contains the identification information
               such as a signature and picture and
               authorizes the person

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             Smart cards

              Innovative application that involves all
               aspects of cryptography
              Has an microprocessor built into the card
              Has enhanced memory and processing
               > several different applications on a
               single card

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             Online banking

              Advantages
              Convenience
              Ubiquity
              Efficiency
              effectiveness

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             Online banking

              Disadvantages
              Start-up may take time
              Learning curve
              Bank site changes
              The trust thing

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              http://www.arx.com/digital-signatures-
                http://computer.howstuffworks.com/encryption5.
                http://money.howstuffworks.com/personal-
                http://computer.howstuffworks.com/encryption.h
                http://www.arx.com/flash/Digital-Signatures-for-

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