{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

1.Introduction - Introduction Reading assignment Chapter 1...

Info icon This preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Introduction Reading assignment: Chapter 1 of Katz & Lindell
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Cryptography Merriam-Webster Online Dictionary: 1. secret writing 2. the enciphering and deciphering of messages in secret code or cipher. Scientific study of techniques for securing digital information, transactions, and distributed computations. 2
Image of page 2
3 Computational Difficulty (One-Way Functions) Pseudorandom Generators And Functions Zero-Knowledge Proof Systems Encryption Schemes Crypto Protocols Sign/MAC Schemes APPLICATIONS A Structural View of Cryptography
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4 Basic objectives of cryptography  Protecting data privacy Data integrity (message authentication): allowing the recipient to check if a received message has been modified. Authentication: Data origin authentication: allowing the recipient to verify the origin of a received message. Entity authentication: allowing the entities of a (connection- oriented) communication to authenticate each other. Non-repudiation: to prevent the sender from later denying that he sent the message.
Image of page 4
5 Main Characters Alice Bob Peggy (prover) Vic (verifier) Eve or Oscar (eavesdropper, opponent)
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
6 Bob                                                Alice Eve
Image of page 6
7 m c E D Bob Alice m key                             key’ Encryption and secrecy Plaintext                 ciphertext                  plaintext
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
8 Encryption and secrecy Encryption protects secrecy of transmitted messages Encryption E k : plaintext m → ciphertext c Decryption D k’ : ciphertext c → plaintext m Encryption key: Decryption key: equal or not equal k k
Image of page 8
9 Symmetric-key encryption Also called secret-key or private-key encryption Encryption key = decryption key D(k, E(k,m)) = m Or, D k (E k (m)) = m
Image of page 9

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
10 Example: Caesar’s shift cipher Plaintexts m
Image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.
  • Spring '10
  • TenH.Lai
  • Cryptography, Encryption, Plaintext                 ciphertext                  plaintext, Bob                                                Alice, new ciphertext c., Alice m

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern