International Journal of Computer Engineering and Applications, ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD

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1 International Journal of Computer Engineering and Applications, Volume XI, Issue IX, September 17, ISSN ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD Namrata Singh 1, Abhigyan Tiwari 2, Dr.Amit Shrivastava 3, Dr. Manish Manoriya 4 1 Student of Computer Science & Engineering SIRTS, Bhopal (Madhya Pradesh),India 2,3,4 Department of Computer Science & Engineering SIRTS,Bhopal(Madhya Pradesh),India ABSTRACT: In network communication system, security is playing most important role. So, for security purpose we are using Cryptography techniques in network communication & Internet. Cryptography is the science by which a readable message (Plain text) will be converting into non-readable message (Cipher text). Substitution and Transposition are two classical methods of Cryptography. In this paper I will discuss about earlier developed few Transposition techniques and a technique by which we can encrypt & decrypt the text which is NEWSO Transposition Method. This technique is the combination of reverse & clockwise rotation technique with directions. More Technique More Security by keeping this in mind I have proposed this method. This paper basically describes transposition method because transposition method is the combination of confusion & diffusion. Keywords: - Cryptography, Clockwise rotation, Encryption, Reverse Method. Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 71

2 ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD [1] INTRODUCTION: In today s world, the modern era is dominated by paperless transactions in business, private or government offices. Due to this there is a great need of protection or security. To protect sensitive text information from unauthorized access cryptography techniques are used. Cryptography or Cryptology, from Greek words, kryptos (hidden or secret) & graphein (writing or study) respectively, is the practice and study of techniques to protect communication in the presence of third party. Cryptography is often called code making. Encryption and Decryption are the two terms of Cryptography which is more important in it. Encryption refers that sensible text (readable text or plain text) converted into insensible text (nonreadable text or cipher text) & just the inverse process of encryption i.e. the cipher text converted into plain text is known as decryption. Plain Text (Hello) Encryption Cipher Text (Y%#23) Cipher Text (Y%#23) Decryption Plain Text (Hello) Figure :1. Encryption and Decryption Process There are two primary ways by which a plain text can be encrypt or decrypt. They are Substitution and Transposition. [2] BACKGROUND STUDY: The Transposition technique performs some permutation over the plain text alphabets that mean the rearrangement of letters in plain text according a rule can make plain text message to cipher text and the receiver decrypt the message by performing the inverse transposition method. Some of them are given below- 1. Rail Fence Cipher Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 72

3 International Journal of Computer Engineering and Applications, Volume XI, Issue IX, September 17, ISSN Simple Columnar 3. Simple Columnar with Multiple rounds 4. Vernam Cipher 5. Route Cipher 6. Myszkowski Cipher 7. Combination 8. Grilles The brief description are given below- 1. Rail Fence Cipher :- The Rail Fence cipher gets its name from the way in which it is encoded. It involves writing of plain text as sequence of diagonals and then reading it row-by-row to produce cipher text. For example, the original plain text message is SIRTS IS THE BRANCH OF SIRT and the cipherer writes out: S R S S H B A C O S R I T I T E R N H F I T Then reads off: SRSSHBACOSRITITERNHFIT It is quite simple to break into for cryptanalyst. 2. Simple Columnar Technique:- In Simple Columnar transposition, the message is written out in row-by-row in a rectangle of a pre-defined length and then read out column by column and the columns are chosen in some random order. For example, the above message will be look Like Figure 2. Figure: 2. Example of Simple Columnar Then the order of columns as some random order i.e. 4, 6, 1, 2, 5 and 3. The text read as TEHTIRFSSASITNISBORHCR 3. Simple Columnar with Multiple rounds:- In Simple columnar there is a drawback which is it is easy just like Rail Fence, to improve this technique we use the Simple columnar technique by using again and again. It means to use the same basic procedure more than once. For example, In above simple columnar if we again apply that procedure. The cipher text after one round are looking as given below- Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 73

4 ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD TEHTIRFSSASITNISBORHCR Then apply second round on it, the message will be look like- Figure:3. Example of Columnar with Multiple rounds This is much more complex to crack as compared to the basic technique. 4. Route Cipher:- In it the plain text is written out in the grid and use the route assigned. For example, the message will be look like S T S E A H S T I S T B N O I J R I H R C F R X Then reads off- TJXRFCRHIRISTSEAHSIONBTS For decryption, the size of grid and the route used is necessary. 5. Vernam Cipher:- The Vernam Cipher is also called as One-Time pad because there is an identical random sequence of letters which was previously somehow produced and securely issued to sender and receiver. The plain text alphabets treated as number in increasing sequence i.e. A=0,B=1,..Z=25. For example, the plain text message HELLO using a one-time pad NQCFJ and the process will be look like- Plain Text H E L L O One-Time Pad N Q C F J Total Cipher Text U U N Q X Figure 2: Example of Vernam Cipher Thus the cipher text which we have got is UUNQX. If there is greater than 26 in total, then subtract 26 from it. 6. Combination: - Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 74

5 International Journal of Computer Engineering and Applications, Volume XI, Issue IX, September 17, ISSN The combination of substitution cipher and columnar transposition will produce a new technique which avoids the weakness of both. 7. Grilles:- It is also known as physical masks with cut-outs. It produces a highly irregular transposition over the period specified by the size of the grilles, but requires the correspondents to keep a physical key secret. [3] PROPOSED METHODOLOGY & EXPECTED OUTCOME: In this section I am going to present my new methodology which name is given as NEWSO Transposition Method. In it as name given I have used the direction as well as rotation also. 1. Process of Encryption- The encryption process of our method which are given below- Step1:- Firstly the plain text message on which we are going to apply our method i.e. SIRTS IS THE BRANCH OF SIRT. Step2:- Take the prime no. position which are 1, 2, 3, 5, 7.etc. on above plain text message just like given below- S I R T S I S T H E B R A N C H O F S I R T Separate the prime no. position letters are- RTITRNFI Reverse of them are given below- IFNRTITR Step 3:- Then remaining letters are- SISSHEBACHOSRT Step4:- The remaining letters then separate by half and reverse them both like that- SISSHEB+ACHOSRT BEHSSIS+TRSOHCA BEHSSISTRSOHCA Step5:- Combine both step 2, 4 and then the first level encrypted message will be look like- IFNRTITRBEHSSISTRSOHCA The total encryption algorithm of first level are given below- Take prime no. position letters and reverse them + Remaining characters separate by half (First half reverse + Second half reverse) Step6:- Everybody knows the directions position in map which are given below- North (N) West (W) East (E) Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 75

6 ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD South (S) Figure 3: The directions in map Step7:- The first level encrypted message letters will be separated by 4 because there are 4 directions. The message will be look like- IFNR TITR BEHS SIST RSOH CA Step 8:- So, simply apply the separated message on direction wise (in way of N-E-W-S) which is given below- (i) I (ii) T N F T I R R (iii) B (iv) S H E S I S T (v) R (vi) C O S A H Step9:- Then, in all clock-wise rotation (Shift by 1) apply and the encrypted message will be look like- NIFRTTIRHBESSSITORSHCA After that the decryption process of our method are given below- Step1:- For decryption, we separate the cipher text message with 4. The cipher text will be look like- NIFR TTIR HBES SSIT ORSH CA Step2:- Keep all the letters in direction wise (in way of N-E-W-S) & then in anti-clockwise rotation which are given below- Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 76

7 International Journal of Computer Engineering and Applications, Volume XI, Issue IX, September 17, ISSN (i) N (ii) T F I I T (iii) H (iv) S E B I S R S T (v) O (vi) C S R A H Step 3:- Then reads the message will be find out- IFNRTITRBEHSSISTRSOHCA Step4:- There are 22 letters such that we can say that the prime no. will be 2, 3, 5, 7, 11, 13, 17 and 19 i.e. 8,so separate them with 8 and remaining 14 characters which will be look like- IFNRTITR + BEHSSISTRSOHCA (First encrypted message) + (Second encrypted message) Step5:- Reverse the first encrypted message which will be like that- RTITRNFI Step6:- Take second encrypted message and separate by half like that- BEHSSIS + TRSOHCA Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 77

8 ENCRYPTION & DECRYPTION PROCESS BY USING NEWSO TRANSPOSITION METHOD Step7:- Reverse both of above separated and encrypted message which will be SISSHEB + ACHOSRT Step8:- First encrypted and second encrypted message we have got this- RTITRNFI + SISSHEBACHOSRT Step9:- In the last we have to put their position characters in that and we have got our plain text message- SIRTS IS THE BRANCH OF SIRT [4] CONCLUSION: Today s we have many cryptography techniques to secure our communication system depending upon our needs. More methods more security by keeping this in our mind I have described this method in this paper. REFERENCES: 1] Preeti Poonia, Praveen Kantha, Comparative Study of Various Substitution and Transposition Encryption Techniques, International Journal of Computer Applications, Volume 145, No. 10, July ] Er. Reema Gupta, Dr. Sukhvir Singh, Pardeep Maan, Efficient Encryption Technique in Cryptography Better Security Enhancement, International Journals of Advanced Research in Computer Science and Software Engineering (IJARCSSE), Volume 4, Issue 5, May ] Yashpalsingh Rajput, Dnyaneshwar Naik, Charudatt Mane, An Improvement Cryptographic Technique to Encrypt Text Using Double Encryption, International Journal of Computer Applications, Volume 86, No. 6, January ] Kashish Goyal, Supriya Kinger, Modified Caesar Cipher for Better Security Enhancement, International Journal of Computer Applications, Volume 73, No. 3, July ] Mu. Annalakshmi, A. Padmapriya, Zigzag Ciphers: A Novel Transposition Method, International Conference on Computing and Information Technology (IC2IT-2013) & International Journal of Computer Applications ( ), ] Sombir Singh, Sunil K. Maakar, Dr. Sudesh Kumar, Enhancing the Security of DES Algorithm Using Transposition Cryptography Techniques, International Journals of Advanced Research in Computer Science and Software Engineering, Volume 3, Issue 6, June ] S G Srikantaswamy, Dr. H D Phaneendra, Improved Caesar Cipher with Random Number Generation Technique and multistage encryption, International Journal of Computing and Information Sciences, vol. 2, No. 4, December ] Ajit Singh, Aarti Nandal, Swati Malik, Implementation of Caesar cipher with Rail Fence for Enhancing Data Security, IJARCSSE, Volume 2, Issue 12, December ] Prof. S.D. Padiya, Prof. D. N. Daknane, Plaintext Based Transposition Method, IJARCSSE, Volume 2, Issue 7, July ] Mohammed AbuTaha, Mousa Farajallah, Radwan Tahboub, Mohammed Odeh, Survey Paper: Cryptography is the Science of Information Security, Vol. 5, Issue 3, 2011 in IJCSS. Namrata Singh, Abhigyan Tiwari, Dr.Amit Shrivastava, Dr. Manish Manoriya 78