Transcript Cryptography - Georgia State University

Cryptography
CSc 8320
Advanced Operating Systems
Barnali Chakrabarty
Overview
What is Cryptography ? Its history
And its fundamentals
 Public and Private Cryptographic Systems
 Current Work
 Future Research

What is Cryptography ?
The process of converting intelligible information called the
plain text into something that is unintelligible, called the cipher text
History of Cryptography

2000 BC in Egypt

Atbash Cipher

Caesar Cipher
Fundamentals of Cryptography
Confidentiality
Authenticity
Integrity
Availability
Nonrepudiation
Public Key Cryptographic
Systems

asymmetric key algorithms
the key used to encrypt a message is not the
same as the key used to decrypt it
Diffie Hellman Algorithm: A public key
Cryptographic Algorithm
Private Key Cryptographic
Systems
- Also called Symmetric encryption
involves using the same key for
encryption and decryption.
One Time Pad: A Private Key
Cryptographic Algorithms
The plain text is combined with a secret
random key only once to produce the
cipher text
Current Work :Research on Elliptic
Curve Cryptography[Q.Qiu04]
Offer major advantages over Traditional
systems like
1.lesser storage
3.smaller keysize
4.increased speed
Future Work: Research on
Quantum Cryptography[5]
 based on photon physics. A photon vibrates as it
travels through space. The angle
of vibration is known as polarization of the photon.
Using different polarizations, the sender can
transmit a unique symmetric key to receiver each
time she needs to send a message. Theoretically,the
eavesdropper has no chance to intercept this key
because of unique properties of quantum physics
References
[1]http://all.net/BOOKS/IP/cHAP2-1.HTML
[2]http://gdp.globus.org/gt4-tutorial/multiplehtml/ch09s03.html
[3]http://en.kioskea.net/contents/crypto/cleprivee.php3
[4] Research on elliptic curve cryptography, Qizhi Qiu ,
Qianxing Xiong,2004
[5]http://www.uhisrc.com/FTB/Cryptography/FTBCryptograph
y.pdf
[6]Distributed Operating Systems and Algorithm Analysis,
Andy Chow & Theodore Johnson,1997
[7]Wikipedia