transposition cipher

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  • 1. TranspositionTransposition CipherCipher A . Antony Alex MCA Dr G R D College of Science CBE Tamil Nadu - India

2. KeywordsKeywords Cryptography EncryptionEncryption Decryption Cipher 3. In cryptography, a TRANSPOSITION CIPHER is a method of encryption by which the positions held by units of plaintext are shifted according to a regular system, soshifted according to a regular system, so that the ciphertext constitutes a permutation of the plaintext. 4. The order of the units is changed. Mathematically a bijective function is used on the characters' positions to encrypt and an inverse function to decrypt.and an inverse function to decrypt. 5. Most Common GameMost Common Game -- AnagramAnagram TSPSH ALSIS EASAM GIMEE THIS IS A SAMPLE MESSAGE 6. Rail Fence cipher Route cipher Columnar transpositionColumnar transposition Double transposition Myszkowski transposition 7. Rail Fence cipherRail Fence cipher 8. Route cipherRoute cipher 9. Columnar transpositionColumnar transposition ZEBRAS "6 3 2 4 1 5 EVLNA CDTES EAROF ODEEC WIREE 10. Double transpositionDouble transposition STRIPE "564231 CAEEN SOIAE DRLEF WEDRE EVTOC 11. Myszkowski transpositionMyszkowski transposition TOMATO 532164 TOMATO 432143 ROFOA CDTED SEEEA CWEIV RLENE 12. Break Columnar TranspositionBreak Columnar Transposition CipherCipher Cryptanalyst must be aware that he is dealing with cipher Frequency of E,T,A,O,I,N, etcFrequency of E,T,A,O,I,N, etc No of Columns Suspect Assumption 13. OneOne--Time PadsTime Pads Random Bit String Converting plain text to bit String Converting plant text into its ASCII Representation EXCLUSIVE OR of two string DisadvantageDisadvantage Key cannot be memorized written The amount of data is limited to key available Sensitivity Can de advantage in computers Using storage devices along with huge data for key transporting. 14. THANK U.THANK U.