Implementation of RSA Algorithm for Speech Data Encryption and Decryption

Md. Ariful HoqueRoll No: MSc 140202Discipline : CSEKhulna University

Data communication.

Vital role of Cryptography.

Phone communication.

E-commerce.

Pay-TV.

Transmitting financial information.

Video Conferencing.

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Cryptosystem.Encryption

Decryption

Symmetric cryptosystem.

RSA cryptographic algorithm.

Uses a pair of related keys -Private key

Public key

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Record 500 Bangla speech words.

Extract data.

Stored in a text file as integer data.

Encrypt and decrypt.

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Speech Word

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Recording of Bangla speech words.

Recorded as wav file.

Sampling rate 8.00 KHz.

Coded in 8 bits PCM.

Speech Word

Preprocessing and Data Extraction

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Discard 58 bytes from beginning.

Extract require voiced data.

Contain silence, unvoiced and voice.

Stored in a text file.

Speech Word

Preprocessing and Data Extraction

Public key {e, n}

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Speech Word

Preprocessing and Data Extraction

Encryption Process

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Public key {e, n}

Speech Word

Preprocessing and Data Extraction

Encryption Process

Private key {d, n}

Public key {e, n}

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Speech Word

Preprocessing and Data Extraction

Encryption Process

Decryption Process

Public key {e, n}

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Private key {d, n}

Speech Word

Preprocessing and Data Extraction

Encryption Process

Decryption Process

Original Speech Word

Private key {d, n}

Public key {e, n}

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Random Number Generator

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Random Number Generator

Rand FIFO

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Random Number Generator

Rand FIFO

PrimalityTester

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

n

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

gcd(e, ∅(n))=11<e< ∅(n)

n

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

gcd(e, ∅(n))=11<e< ∅(n)

e n

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

gcd(e, ∅(n))=11<e< ∅(n)

e.d =1mod ∅(n0 ≤d ≤n

e n

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Random Number Generator

Rand FIFO

PrimalityTester

Prime FIFO

N=p*q∅(n)=(p-1)(q-1)

gcd(e, ∅(n))=11<e< ∅(n)

e.d =1mod ∅(n0 ≤d ≤n

d e n

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e n Public key

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d

e n

n

Public key

Private key

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M

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M

e

n

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M

e

n

Modular Exponentiation Me mod n

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M

e

n

CModular Exponentiation Me mod n

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C

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C

d

n

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C

d

n

Modular Exponentiation Cd mod n

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C

d

n

MModular Exponentiation Cd mod n

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Input: A, B, n Output: E = AB mod n

LR binary method

E <= 1; for i = k-1 to 0

If Bi =1E <= A*E mod nend if

if i ≠ 0 E <= E*E mod n; end if

end for return E;

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Objective.

500 speech words recorded.

Saved as .wav format.

Extracted integer data.

Taken txt file as input.

Produce unreadable message.

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RSA algorithm used to encrypt and decrypt.

M lies in the range .

Encrypt 500 word at a time.

Limitations.

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Thanks To All

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