IT-SEM_6 Cryptography & Network Security 1. Differentiate symmetric and asymmetric key cryptography. Draw the design model of symmetric key cryptography. 2. Use Playfair cipher to Decrypt the following message: “Must see you over Cadogan West. Coming at once” Key: EXAMPLE 3. Enlist block cipher modes of operation. Justify the use of Electronic Codebook (ECB) mode in Cipher Block Chaining (CBC) mode.Explain counter mode of DES operation. 4. Differentiate: Stream cipher and block cipher 5. Apply Railfence cipher approach to Encrypt the following message: “Give me the top ten possible plaintexts” Key for Railfence cipher: 3 6. Draw the design process of DES encryption and explain the round function of DES. 7. Discuss attack on double DES? 8. Encrypt the message M = 9 using RSA with the following parameters: e = 3 and n = 5*11. Then regenerate the plaintext value back based on cipher text value. 9. In a public key cryptosystem using RSA algorithm, user uses two prime numbers 5 and 7. He chooses 11 as Encryption key , find out decryption key. What will be the ciphertext, if the plaintext is 2 10. Explain key pair generation using RSA algorithm & Explain encryption and decryption using RSA. 11. Explain Diffie Hellman key exchange algorithm.Consider a Diffie-Hellman scheme with a common prime q=11 and a primitive root α=2. (i) Show that 2 is a primitive root of 11. (ii) If user A has public key YA=9, what is A’s private key XA? (iii) If user B has public key YB=3, what is the shared secret key K, shared with A? 12. Define the following terms:Masquerade attack 13. Discuss man-in-the middle attack on Diffie-Hellman key exchange. 14. Describe various steps of AES.Draw the design process of AES round function and explain the sub-nibble transformation and shift row mechanism in detail with example. 15. Differentiate confidentiality and authentication. 16. Explain double and triple DES. 17. For Diffie-Hellman algorithm, two publicaly known numbers are prime number 353 and primitive root of it is 3. A selects the random integer 97 and B selects 233. Compute the public key of A and B. Also compute common secret key. 18. Explain four different stages of AES(Advance Encryption standard)structure. 19. Given key K= 2 2 19 21 18 21 17 17 5 and plaintext =”ney”. Find out the ciphertext applying Hill Cipher. Is Hill cipher strong against ciphertext only attack or known plaintext attack? Justify the answer 20. How cryptanalyst can exploit the regularities of the language? How digrams can solve this problem? Use the key “hidden” and encrypt the message “Message” using playfair cipher. 21. Explain the rail fence cipher. 22. Construct a Playfair matrix with the key “engineering”. And encrypt the message “impossible” 23. Define Cryptography and Cryptanalysis. Draw and explain conventional cryptosystem. 24. Write a note on Hill Cipher. 25. Explain the key generation in DES algorithm. 26. Explain the key generation in AES algorithm. 27. What is the purpose of the S-boxes in DES? Explain the avalanche effect. 28. In a public key system using RSA, the cipher text intercepted is C=10 which is sent to the user whose public key is e=5, n=35. What is the plaintext M? 29. Why mode of operation is defined for block ciphers? Compare the block cipher modes of operation? 30. Explain RSA algorithm in detail with suitable example. 31. Explain the Deffie Hellman key exchange scheme in detail with an example 32. Perform encryption and decryption using RSA algorithm for following: p=3;q=13,e=5;M=10 33. Explain the single round of DES algorithm. 34. Explain Playfair cipher technique in detail. Find cipher text for plain text ‘GTUINSEXAM’ using ‘STUDY’ as key. 35. Calculate all the values of RSA assuming two primes p=17 and q=11. Assume other values appropriately. 36. Encrypt the message “GTU Examination” using the Hill cipher algorithm with the key matrix 4 15 5 17 Show your calculations and the result. 37. Perform encryption in Playfair Cipher algorithm with plain text as“INFORMATION AND NETWORK SECURITY”, Keyword is“MONARCHY”. (Note: 1.Put j and i both combine as a single field in 5*5 matrix). 38. Explain process of encryption in RSA Algorithm with suitable example.(Prime Number P,Q and Encryption Key E is given for reference) P=7,Q=17, E=7 39. Encrypt the message "meet me at the usual place " using the Hill cipher with the key 9 4 5 7
There are no better lectures than these of CNS, You have explained every concept in detail that's very helpful indeed. Great, Thanks man Btw Can we have the pdf of these notes?
When we attack meet in the middle,: E ( k1, P ) -> 2^56 possible results D ( k2, C) -> 2^56 possible results => compare two set results make us 2^56 * 2^56 = 2^112 cases. I think 2 ^ 57 security is not enough ???
In 14:49, the explanation is not right. (k1,k2) has 2^56*2^56= 2^112 choices (as both k1and k2 has 2^56 choices). But due to MITM attack it gives the security of 2^57 bits only. I have enjoyed your last two videos but this disappointed me.
(sir ya kon say algorithm say ho ga) Data encryption algorithm should be block cipher having 128 bit plaintext binary blocks. 2. Master encryption key should be 128 bits longer and for each plaintext block there should be a different encryption key. 3. Algorithm must have permutation/transposition operation as per your own logic. 4. Algorithm must have substitution operation as per your own logic. 5. Algorithm must have some other encryption operations alike AND, XOR or any other similar operation(s) designed by you. 6. Algorithm should has a separate interface under separate button for performing encryption and decryption as per need. You can use any programing language of your choice.
Great lecture, but I think the last point about brute forcing is wrong..Because , the attacker will have to check for all possibilities which is 2^56 * 2^56 = 2^112. Else, engineers wud have never invented DES2 if it was taking only twice the time.😅😅
Wait, 2^56 = 72,05,75,94,03,79,27,936 for each encryption and decryption so total, 1,44,11,51,88,07,58,55,872 operation in worst case. U also need plain text prediction which is almost impossible. Is it really feasible?
Sir ji kamal ho aap aapke video se exam ki tayari matlab mauj
Keep doing it
No channel has forced me to subscribe them as much this this playlist has. Awesome work buddy. Keep it up. 👍🏼👍🏼
You saved me for CNS thank you!!!!😍😍😍😍
just amazing explaination with reference and notes love it sir
IT-SEM_6
Cryptography & Network Security
1. Differentiate symmetric and asymmetric key cryptography. Draw the design model of
symmetric key cryptography.
2. Use Playfair cipher to Decrypt the following message:
“Must see you over Cadogan West. Coming at once”
Key: EXAMPLE
3. Enlist block cipher modes of operation. Justify the use of Electronic Codebook (ECB)
mode in Cipher Block Chaining (CBC) mode.Explain counter mode of DES operation.
4. Differentiate: Stream cipher and block cipher
5. Apply Railfence cipher approach to Encrypt the following message:
“Give me the top ten possible plaintexts”
Key for Railfence cipher: 3
6. Draw the design process of DES encryption and explain the round function of DES.
7. Discuss attack on double DES?
8. Encrypt the message M = 9 using RSA with the following parameters: e = 3 and n =
5*11. Then regenerate the plaintext value back based on cipher text value.
9. In a public key cryptosystem using RSA algorithm, user uses two prime
numbers 5 and 7. He chooses 11 as Encryption key , find out decryption
key. What will be the ciphertext, if the plaintext is 2
10. Explain key pair generation using RSA algorithm & Explain encryption and decryption
using RSA.
11. Explain Diffie Hellman key exchange algorithm.Consider a Diffie-Hellman scheme with
a common prime q=11 and a primitive root α=2.
(i) Show that 2 is a primitive root of 11.
(ii) If user A has public key YA=9, what is A’s private key XA?
(iii) If user B has public key YB=3, what is the shared secret key K, shared with A?
12. Define the following terms:Masquerade attack
13. Discuss man-in-the middle attack on Diffie-Hellman key exchange.
14. Describe various steps of AES.Draw the design process of AES round function and
explain the sub-nibble transformation and shift row mechanism in detail with example.
15. Differentiate confidentiality and authentication.
16. Explain double and triple DES.
17. For Diffie-Hellman algorithm, two publicaly known numbers are prime
number 353 and primitive root of it is 3. A selects the random integer 97
and B selects 233. Compute the public key of A and B. Also compute
common secret key.
18. Explain four different stages of AES(Advance Encryption standard)structure.
19. Given key K=
2 2 19
21 18 21
17 17 5
and plaintext =”ney”. Find out the ciphertext applying Hill Cipher. Is Hill cipher strong
against ciphertext only attack or known plaintext attack? Justify the answer
20. How cryptanalyst can exploit the regularities of the language? How
digrams can solve this problem? Use the key “hidden” and encrypt the
message “Message” using playfair cipher.
21. Explain the rail fence cipher.
22. Construct a Playfair matrix with the key “engineering”. And encrypt the message
“impossible”
23. Define Cryptography and Cryptanalysis. Draw and explain conventional cryptosystem.
24. Write a note on Hill Cipher.
25. Explain the key generation in DES algorithm.
26. Explain the key generation in AES algorithm.
27. What is the purpose of the S-boxes in DES? Explain the avalanche effect.
28. In a public key system using RSA, the cipher text intercepted is C=10 which is sent to the
user whose public key is e=5, n=35. What is the plaintext M?
29. Why mode of operation is defined for block ciphers? Compare the block cipher modes of
operation?
30. Explain RSA algorithm in detail with suitable example.
31. Explain the Deffie Hellman key exchange scheme in detail with an example
32. Perform encryption and decryption using RSA algorithm for following:
p=3;q=13,e=5;M=10
33. Explain the single round of DES algorithm.
34. Explain Playfair cipher technique in detail. Find cipher text for plain text
‘GTUINSEXAM’ using ‘STUDY’ as key.
35. Calculate all the values of RSA assuming two primes p=17 and q=11. Assume other
values appropriately.
36. Encrypt the message “GTU Examination”
using the Hill cipher algorithm with the key matrix
4 15
5 17 Show your calculations and the result.
37. Perform encryption in Playfair Cipher algorithm with plain text as“INFORMATION
AND NETWORK SECURITY”, Keyword is“MONARCHY”. (Note: 1.Put j and i both
combine as a single field in 5*5 matrix).
38. Explain process of encryption in RSA Algorithm with suitable example.(Prime Number
P,Q and Encryption Key E is given for reference) P=7,Q=17, E=7
39. Encrypt the message "meet me at the usual place " using the Hill cipher with the key
9 4
5 7
Pass?
thank you so much bro , really helpful
Thanks a lot bhiya for your all hardwork 🙏🙏🙏
Excellent teaching skills....
Thanks a lot..
There are no better lectures than these of CNS, You have explained every concept in detail that's very helpful indeed.
Great, Thanks man
Btw Can we have the pdf of these notes?
he wont send them, because you will stop seeing his videos,lol
arey Narendra Modi's daughter 😳
Your all video's are superb!! 👍
Your explanation is very easy to understand sir. Thank you so much 😊
always follow your channel ,the way you explain just too good.
great video sir👌👌
Thank you so much brother. Your explanation is very easy to understand. Keep it up.
This is very informative to us😊
ye modes of des hai?
When we attack meet in the middle,:
E ( k1, P ) -> 2^56 possible results
D ( k2, C) -> 2^56 possible results
=> compare two set results make us 2^56 * 2^56 = 2^112 cases.
I think 2 ^ 57 security is not enough ???
Same doubt....
Same doubt
Thanks For this videos ..Keep doing..helps a lot for INS..😊
More videos will be uploaded in this week 🤘 #StayTuned
@@AbhishekSharmaDit tomorrow will final exam of INS (GTU)..plz make video asap
@@AbhishekSharmaDit X
will you share your hand written notes to us?
in form of soft copy?
2DEC is not double secure, this is one of the main drawbacks of this technique. It gives only 57 bits of security!!
bhai kya samjhaya apne. maza agaya
wow same bro same
mere paas bhi same hi black pen hai
thank you for such a great explanation on this DES series..........im subscribing you and hope to see more contents like this from you......
Ha vo
very well explained!!!
Sir which reference book are you using ?
Do we use the same procedure for both encryption and decryption in DES ?
can you please tell me the name of book you use in this video
Understood it much better with ur videos
2:30 which book is this ?
What is the name of the book you are using for reference
In 14:49, the explanation is not right. (k1,k2) has 2^56*2^56= 2^112 choices (as both k1and k2 has 2^56 choices). But due to MITM attack it gives the security of 2^57 bits only. I have enjoyed your last two videos but this disappointed me.
(sir ya kon say algorithm say ho ga)
Data encryption algorithm should be block cipher having 128 bit plaintext binary blocks.
2. Master encryption key should be 128 bits longer and for each plaintext block there should be a different encryption key.
3. Algorithm must have permutation/transposition operation as per your own logic.
4. Algorithm must have substitution operation as per your own logic.
5. Algorithm must have some other encryption operations alike AND, XOR or any other similar operation(s) designed by you.
6. Algorithm should has a separate interface under separate button for performing encryption and decryption as per need. You can use any programing language of your choice.
AES
Excellent lecture. Pls send us written notes.
Aoa i have a question that what are counter measures or prevention of this attack
Great lecture, but I think the last point about brute forcing is wrong..Because , the attacker will have to check for all possibilities which is 2^56 * 2^56 = 2^112. Else, engineers wud have never invented DES2 if it was taking only twice the time.😅😅
Please arrange the lectures in the correct order in the series...it really creates a lot of confusiom
can you provide full notes in pdf please?
Sir i can not found man in the middle attack in ur lecture series.....can i expect for that..??
can you provide the notes, you have made?
Why doubleDES should not be applied? If applied, what security problems arise? Thanks I want to know that
Sir threats: protection in os: memory and address protection,access control file protection,user authentication iss video Dale plz
What is the name of that book?
Cryptography and network security by Behrouz A Forouzan
In double DES you said that we'll encrypt plain text , but attacker want is plain text
why would we encrypt it ?
I didn't get you , can you please elaborate.
8:00
Notes upload karna chahiye
Wo bhai thoda time deke example v karwa dete isspar
How the brute force attack will launch over 2 des aya question hey do any one know?
Wait,
2^56 = 72,05,75,94,03,79,27,936 for each encryption and decryption
so total, 1,44,11,51,88,07,58,55,872 operation in worst case. U also need plain text prediction which is almost impossible.
Is it really feasible?
ya assigment ha ap k lecture say sari samaj a jati ha ya ni samaj a raha .
Bhai mera 4 din bad exam h jese ye apne likha hai vese likh do mah shi rhega
Bilkul lokh sakte ho
@@AbhishekSharmaDit thnk u.brodr answer krne ke liye..
Sir notes 🗒️ iska de do Ap please
Please Mr. Abhishek, Can you speak more in English.
too much adds. Its a negative point but your way of teaching is good