1 00:00:08,440 --> 00:00:11,320 Let us continue with an overview of cryptography. 2 00:00:12,100 --> 00:00:20,080 In this video, we will discuss to advance asymmetric algorithms that the RNC and the development algorithm. 3 00:00:21,650 --> 00:00:30,140 RSA cryptography was developed by Ron Reversed additionally and Leonhard Edelman at Massachusetts Institute 4 00:00:30,140 --> 00:00:38,540 of Technology M.I.T. in 1977, Oddisee is a crypto system for public encryption, widely used for securing 5 00:00:38,540 --> 00:00:45,560 sensitive data, particularly when being sent over an insecure network so that the Internet in other 6 00:00:45,710 --> 00:00:51,850 cryptography, both the public and private keys can encrypt the message, while the opposite creeky 7 00:00:51,860 --> 00:00:53,360 from the one used to encrypt. 8 00:00:53,360 --> 00:00:55,490 The message is used to decrypt it. 9 00:00:56,460 --> 00:01:01,140 Oracy implements a public system as well as digital signatures. 10 00:01:02,230 --> 00:01:08,050 For public key encryption in Oddisee, encryption keys, the public when the decryption keys are not 11 00:01:08,050 --> 00:01:14,870 so, so only the person with the correct decryption key can decipher an encrypted message. 12 00:01:15,880 --> 00:01:21,700 The keys must be made in such a way that the decryption key may not be easily deduced from the public 13 00:01:21,700 --> 00:01:22,480 encryption key. 14 00:01:23,080 --> 00:01:26,350 Everyone has their own encryption and decryption keys. 15 00:01:27,810 --> 00:01:33,570 For digital signatures in oracy, the receiver may need to verify that the transmitter message actually 16 00:01:33,570 --> 00:01:34,980 originated from the sender. 17 00:01:35,160 --> 00:01:36,150 That is the signature. 18 00:01:37,220 --> 00:01:43,340 This has been using the same decryption key and the signature can be later verified by anyone using 19 00:01:43,340 --> 00:01:48,170 the corresponding public encryption, key signatures therefore cannot be forged. 20 00:01:48,830 --> 00:01:52,580 Also, no sign of conflict or deny having the sign of message. 21 00:01:54,150 --> 00:01:59,960 On your screen, you can see the example of Irisa algorithm, but first let us have a background. 22 00:02:00,840 --> 00:02:06,570 The security of the Irish logarithm has so far been validated since no one attempts to break it. 23 00:02:06,770 --> 00:02:11,310 It has been successful mainly because of the difficulty affecting large numbers that there is. 24 00:02:11,310 --> 00:02:15,000 And is there A and B are large prime numbers. 25 00:02:16,200 --> 00:02:18,750 Sea is, however, a relatively slow algorithm. 26 00:02:19,170 --> 00:02:23,720 And because of this, it is less commonly used to directly encrypt user data. 27 00:02:24,550 --> 00:02:31,540 I say, as I said, is an estimate cryptographic algorithm that enables public encryption for security 28 00:02:31,590 --> 00:02:38,050 transmission in this algorithm, two sets of keys are generated, public and private key. 29 00:02:38,960 --> 00:02:44,480 The security of this algorithm is based on the practical difficulty of factorization, of product of 30 00:02:44,480 --> 00:02:50,420 two very large prime numbers multiplying, two given by numbers to get the parties easy. 31 00:02:50,840 --> 00:02:57,350 But determining the original number from the third is considered an invisible prison due to the time 32 00:02:57,350 --> 00:03:01,610 it would take using even today's most powerful supercomputers. 33 00:03:02,270 --> 00:03:03,860 This is called factoring problem. 34 00:03:04,860 --> 00:03:11,310 Let us consider two components of this algorithm is called the seven, which is the public component, 35 00:03:12,000 --> 00:03:17,940 which everybody can see, and B, which is two seven five three in our case, is the private company, 36 00:03:18,210 --> 00:03:26,490 which is only reserved for the authority your public will be is equal maybe, which will be accessible 37 00:03:26,490 --> 00:03:34,460 to everyone and your private key is equal be consider the as the plaintext and C as a ciphertext. 38 00:03:35,100 --> 00:03:42,070 Therefore the encryption function will be directed to Ma'rib is equal to the years to seven being more 39 00:03:42,300 --> 00:03:43,260 three, two, three, three. 40 00:03:43,560 --> 00:03:47,190 And the decryption function will be Serres more Ebbie. 41 00:03:47,320 --> 00:03:50,250 This series to two seven five three more. 42 00:03:50,520 --> 00:03:51,700 Three, two, three, three. 43 00:03:52,410 --> 00:04:00,480 Let us consider the example that we have to include the value 123 to include plaintext veloute. 44 00:04:00,570 --> 00:04:01,680 It is 123. 45 00:04:02,260 --> 00:04:10,110 Encryption of 123 will be 123 res 217 more three, two, three three which is equal to eight fifty five 46 00:04:11,100 --> 00:04:12,430 to decrypt the ciphertext. 47 00:04:12,600 --> 00:04:14,490 That is the value of eight fifty five. 48 00:04:14,820 --> 00:04:16,680 The decryption function of eight. 49 00:04:16,680 --> 00:04:22,230 Fifty five will be eight fifty first two seven five three more three two three three. 50 00:04:22,260 --> 00:04:23,760 That is equal to 123. 51 00:04:24,980 --> 00:04:31,370 So as of now, you must have known that if we share our private key with anyone, then it's easy to 52 00:04:31,370 --> 00:04:33,070 decrypt the value there. 53 00:04:33,150 --> 00:04:38,060 Therefore, the thing you should remember is that you should keep your private key secure. 54 00:04:38,270 --> 00:04:42,080 In this case, your priority is to defeat Hillman. 55 00:04:43,250 --> 00:04:49,520 The Hellman is a cryptographic protocol that allows two parties to establish a shirkey over an insecure 56 00:04:49,640 --> 00:04:49,870 and. 57 00:04:51,140 --> 00:04:56,240 Diffie and Hilman came up with the encryption method that uses only a one wavefunction. 58 00:04:57,160 --> 00:05:02,500 Many algorithms that were used before for encryption could be hacked because the use functions that 59 00:05:02,500 --> 00:05:06,140 were doing so if someone intercepts an encrypted message. 60 00:05:06,310 --> 00:05:13,120 The information could be retrieved using the security of the message that the algorithm solves the problem 61 00:05:13,120 --> 00:05:14,150 of distribution. 62 00:05:14,350 --> 00:05:21,580 Actually, the filmon was independently developed a few years earlier by Malcolm Davidson of the British 63 00:05:21,580 --> 00:05:24,040 Intelligence Service, but it was classified. 64 00:05:25,460 --> 00:05:31,280 Deferment is a way for two parties to securely generate a key for them to encrypt data in a subsequent 65 00:05:31,280 --> 00:05:31,980 conversation. 66 00:05:32,660 --> 00:05:39,980 It works like this that Alice and Bobby, two people who want to have an encrypted chat, Alice and 67 00:05:39,980 --> 00:05:44,730 Bob, are on separate islands and this is trying to send a box of gold. 68 00:05:44,750 --> 00:05:50,540 But they do not want ever truly to be able to take the gold to protect it. 69 00:05:50,940 --> 00:05:54,680 Alice is a lock and key and Bob has a different lock and key. 70 00:05:55,460 --> 00:05:59,180 Alice cannot open Bob's lock and Bob cannot opens Alice Lock. 71 00:06:00,390 --> 00:06:03,480 When the box is on a board through an intercepted. 72 00:06:04,620 --> 00:06:09,400 Truly can open only an unlocked box and cannot break the locks of Elizabeth. 73 00:06:09,960 --> 00:06:14,910 So how can I send the box of gold to Bob without truly taking the gold? 74 00:06:15,840 --> 00:06:17,480 So what is the answer? 75 00:06:18,440 --> 00:06:25,400 Alice puts her lock on the box and sends it to Bob, Bob then puts his lock on the box as well and sends 76 00:06:25,400 --> 00:06:26,270 it back to Alice. 77 00:06:27,080 --> 00:06:30,470 Alice will then unlock her lock and send it to Bob. 78 00:06:30,920 --> 00:06:33,140 Bob will then unlock his lock. 79 00:06:33,140 --> 00:06:40,520 And the Treadgold noticed that this doesn't stop Trudy from intercepting the bolt, cutting his own 80 00:06:40,520 --> 00:06:42,570 lock on it and sending it back to Alice. 81 00:06:42,830 --> 00:06:47,930 So in reality, additional security is needed to make sure Trudy is not impersonating Bob. 82 00:06:48,260 --> 00:06:52,490 Therefore, Diffie 11 algorithm's comes in use in this case. 83 00:06:52,850 --> 00:06:58,640 In the next lecture, will hashing with two types of fishing in the five and S.A.G..