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Data Compression and Encryption* - Dec 16
Electronics And Telecomm (Semester 7)
Total marks: 80
Total time: 3 Hours
INSTRUCTIONS
(1) Question No. 1 is compulsory.
(2) Attempt any three from remaining five questions.
(3) Assume suitable data wherever necessary.
- a) Explain different redundancies in data and how they are used for data compression. Also give evaluation parameters for compression techniques.
b) What are the goals of cryptographic systems? Describe various attacks compromising these goals. 1486
c) State Fermat's Little Theorem, Euler's Theorem in modular arithmetic. What is Euler's Totient function? Compute $\phi$(37), $\phi$(35), and $\phi$(75). 1046 1047
d) Give an example of each: 1) Substitution cipher 2)Transposition cipher 3) Stream cipher 4) Block cipher 1488
e) Explain extended Euclid's algorithm, and compute multiplicative inverse of 7 modulo-160.
- i) Show that 2 is primitive root of 11.
- ii) If user A has public key Y$_A$=9, what is A's private key X$_A$?
- iii) If user B has public key Y$_B$=3, what is the shared secret key K?
a) Digital Signatures 1060
b) H.264 Video coding standard 1038
c) Ethical Hacking 1070
d) Digital Immune Systems 1068
e) Elliptic curves for cryptography 1057