• AES: Advanced Encryption Standard (2000) – Mix several times key and plaintext – Complex method – Knowledge of Plaintext and Cyphertext Knowledge of the key
Symmetric Encryption Problem
• • • • •
Alice and Bob : same key How does Alice send the key? Alice and Bob : know each other? What append when Eve gets the key? …
Asymmetric Encryption
Bob
Alice
Eve
Asymmetric Encryption
Bob
Alice
Eve
Asymmetric Encryption
Bob
Alice
Eve
Asymmetric Encryption • Two keys – Public key – Private key
• Use mathematical functions – One-way functions – Trapdoor
• Need high computation power to deduce the plaintext from the cyphertext (try all private keys)
Asymmetric Encryption RSA
• Rivest, Shamir, Adleman (1978) – – – – – –
Most of algorithms based on RSA Use difficulty of factorization of large numbers Private key: 2 large prime numbers p,q Public key: n=p*q Plaintext m, cyphertext c = f(m,n) Decrypt: m=g(c,p,q)
We consider (in the framework of algorithmic information theory) questions of the following type: .... The strings a and b are independent (have logarithmic mutual.
Page 1 ...... A second drawback is the key management problemâin a network of N ..... For the desired level of security, do the protocols meet performance.
message may be a 1GB video file, a 10MB music file, a 1KB email message, or even a single ...... Not surprisingly, English text contains enough redundancy that.
when we update our lecture notes I also update these notes. ...... As another example let E be the random variable representing letters in English text. ...... We make a record of the letters and the positions for which one letter encrypts to the ...
probability theory and algebra is provided in the appendices. ...... 17.5 Quantum attacks on number theoretic problems . .... 19.5 Sigma protocols: examples .
Communication Framework using Authenticated Encryption in Wireless ... related to key management in quantum cryptography like how quantum access nodes ... for Security of Software, Hodorogea and Otto, emphasize the need of robust security .... Illust
Alice communicates with the White rabbit via a network. Secret. 3 / 52 ... Something that you have ... Page 16 ... Leon Alberti devised a cipher wheel, and described the principles .... Put your message in a black bag, you can not read anything.
CrypTool was developed during the end-user awareness program at Deutsche Bank in order to .... 331,252 individuals co-operated over the internet to find the key. ...... 1947, and the second was taken from âLake Wobegon Daysâ, by Garrison Keillor,
List of Algorithms ix. List of Tables xiv. List of Figures .... 5.3.3 Error messageanalysis . ...... of authenticating its holder ËA to the mainframe computer B at the ... thentication code (MAC) algorithm such as HMAC to achieve data integrity and
May 5, 2017 - passion and energy, for all the fruitfull discussions and moments shared. ..... A Practical Solution for Efficient Homomorphic-Ciphertext Compression . ... In this chapter we will introduce the basic notions that describe the context ..
tion, e.g. AES, and a coupon-based signature function, e.g. GPS. ... tools, namely low cost cryptographic primitives and an authentication protocol of the reader.
Walter introduced at CHES 2001 the Big Mac attack on rsa [14]. It consists in com- paring the power trace of two multiplications, and detect if they share a common operand. The Big Mac attack as presented in [14] is not applicable on ecc because the
seek to achieve a symmetric outcome Here, by contrast, the impetus to create a public/private key pair must originate in a particular user, who will become the ...
key using two communication channels: one quantum communication channel over which single polarized photons are sent from Alice to Bob, and a classical ...
