1 00:00:00,000 --> 00:00:02,000 [Powered by Google Translate] [RSA] 2 00:00:02,000 --> 00:00:04,000 [Rob Bowden] [Tommy MacWilliam] [Harvard Universiteti] 3 00:00:04,000 --> 00:00:07,000 [Bu CS50 edir.] [CS50.TV] 4 00:00:07,000 --> 00:00:11,000 Nin RSA, data 艦ifreleme 眉莽眉n geni艧 istifad蓹 alqoritm n蓹z蓹r salaq. 5 00:00:11,000 --> 00:00:16,000 Sezar v蓹 Vigen猫re ciphers kimi Encryption alqoritml蓹r 莽ox t蓹hl眉k蓹siz deyil. 6 00:00:16,000 --> 00:00:20,000 Olan Sezar parol il蓹, bir sald谋rgan谋n yaln谋z 25 m眉xt蓹lif d眉ym蓹l蓹ri c蓹hd laz谋md谋r 7 00:00:20,000 --> 00:00:22,000 mesaj d眉z m蓹tn almaq 眉莽眉n. 8 00:00:22,000 --> 00:00:25,000 The Vigen猫re parol the Caesar parol art谋q t蓹hl眉k蓹siz olsa 9 00:00:25,000 --> 00:00:28,000 莽眉nki d眉ym蓹l蓹ri 眉莽眉n b枚y眉k axtar谋艧 alan, bir d蓹f蓹, bir sald谋rgan谋n 10 00:00:28,000 --> 00:00:30,000 bir Vigen猫re parol ild蓹 蓹sas uzunlu臒u bilir 11 00:00:30,000 --> 00:00:34,000 olan 艧ifreli m蓹tn n眉mun蓹l蓹ri t蓹hlil vasit蓹sil蓹 m眉蓹yy蓹n edil蓹 bil蓹r 12 00:00:34,000 --> 00:00:38,000 the Vigen猫re cipher daha t蓹hl眉k蓹siz Caesar parol 莽ox deyil. 13 00:00:38,000 --> 00:00:42,000 RSA, dig蓹r t蓹r蓹fd蓹n, bu kimi h眉cumlara h蓹ssas deyil. 14 00:00:42,000 --> 00:00:45,000 Bu Caesar parol v蓹 Vigen猫re parol eyni d眉ym蓹sind蓹n istifad蓹 15 00:00:45,000 --> 00:00:47,000 encrypt v蓹 decrypt mesaj h蓹m d蓹. 16 00:00:47,000 --> 00:00:51,000 Bu 蓹mlak bu ciphers simmetrik 蓹sas alqoritml蓹ri edir. 17 00:00:51,000 --> 00:00:54,000 Simmetrik 蓹sas alqoritml蓹ri olan 蓹sas problem 18 00:00:54,000 --> 00:00:57,000 onlar mesaj 艦ifreleme v蓹 g枚nd蓹rilm蓹si bir etibar ki, 19 00:00:57,000 --> 00:00:59,000 v蓹 bir q蓹bul v蓹 mesaj decrypting 20 00:00:59,000 --> 00:01:03,000 art谋q onlar h蓹m istifad蓹 ed蓹c蓹k 蓹sas haqq谋nda upfront raz谋l谋q var. 21 00:01:03,000 --> 00:01:06,000 Amma burada bir ba艧lan臒谋c problem bir q蓹d蓹r var. 22 00:01:06,000 --> 00:01:10,000 Nec蓹 眉nsiyy蓹t etm蓹k ist蓹yir蓹m ki, 2 komp眉ter aras谋nda bir gizli 蓹sas yaratmaq edirsiniz? 23 00:01:10,000 --> 00:01:16,000 茝sas gizli olmal谋d谋r, onda biz 蓹sas 艧ifrelemek v蓹 decrypt 眉莽眉n bir yol laz谋md谋r. 24 00:01:16,000 --> 00:01:18,000 Biz b眉t眉n simmetrik 蓹sas Kriptoqrafiya deyil 25 00:01:18,000 --> 00:01:21,000 sonra biz yaln谋z eyni problem qay谋da etdik. 26 00:01:21,000 --> 00:01:25,000 RSA, dig蓹r t蓹r蓹fd蓹n, d眉ym蓹l蓹ri bir c眉t istifad蓹 27 00:01:25,000 --> 00:01:28,000 parol 莽枚zme 眉莽眉n 艧ifr蓹l蓹m蓹 v蓹 dig蓹r 眉莽眉n. 28 00:01:28,000 --> 00:01:32,000 Bir ictimai 蓹sas adlan谋r v蓹 dig蓹r x眉susi a莽ar谋 edir. 29 00:01:32,000 --> 00:01:34,000 Ictimai 蓹sas messages 艧ifrelemek 眉莽眉n istifad蓹 olunur. 30 00:01:34,000 --> 00:01:38,000 Onun ad谋 il蓹 tapmaq kimi, biz bizim ictimai 蓹sas pay谋 ed蓹 bil蓹rsiniz 31 00:01:38,000 --> 00:01:43,000 biz 艧ifr蓹li mesaj t蓹hl眉k蓹sizlik 枚d眉n olmadan ist蓹diyiniz h蓹r k蓹s. 32 00:01:43,000 --> 00:01:45,000 Mesajlar谋m ictimai a莽ar谋 istifad蓹 艧ifrelenir 33 00:01:45,000 --> 00:01:49,000 yaln谋z m眉vafiq x眉susi a莽ar il蓹 艧ifresi 莽枚z眉len bil蓹r. 34 00:01:49,000 --> 00:01:53,000 Siz ictimai 蓹sas pay谋 ed蓹 bil蓹rsiniz baxmayaraq, siz h蓹mi艧蓹 x眉susi a莽ar谋 gizli saxlamaq laz谋md谋r. 61 00:01:55,000 --> 00:01:58,000 v蓹 yaln谋z x眉susi a莽ar谋 decrypt mesaj 眉莽眉n istifad蓹 edil蓹 bil蓹r 62 00:01:58,000 --> 00:02:02,000 2 istifad蓹莽i RSA il蓹 mesaj 艧ifr蓹li g枚nd蓹rm蓹k ist蓹yirsinizs蓹 63 00:02:02,000 --> 00:02:07,000 geri v蓹 ir蓹li d蓹 istifad蓹莽il蓹r 枚z d枚vl蓹t v蓹 枚z蓹l 蓹sas c眉t laz谋md谋r. 64 00:02:07,000 --> 00:02:10,000 Istifad蓹莽i 1 istifad蓹莽i 2 Mesajlar谋m 65 00:02:10,000 --> 00:02:15,000 yaln谋z user 2 istifad蓹莽i 1 istifad蓹莽i 2 蓹sas c眉t, mesaj istifad蓹 66 00:02:15,000 --> 00:02:17,000 yaln谋z istifad蓹莽i 1 蓹sas c眉t istifad蓹 edin. 67 00:02:17,000 --> 00:02:21,000 2 ayr谋-ayr谋 艧ifrelemek d眉ym蓹l蓹ri v蓹 decrypt mesaj var ki, 68 00:02:21,000 --> 00:02:24,000 RSA bir asimmetrik a莽ar alqoritmi edir. 69 00:02:24,000 --> 00:02:28,000 Biz ba艧qa bir komp眉ter g枚nd蓹rm蓹k 眉莽眉n ictimai 蓹sas 艧ifrelemek ehtiyac yoxdur 70 00:02:28,000 --> 00:02:31,000 蓹sas h蓹r halda ictimai g枚st蓹rir. 71 00:02:31,000 --> 00:02:33,000 Bu RSA eyni ba艧lan臒谋c problem yoxdur o dem蓹kdir ki, 72 00:02:33,000 --> 00:02:36,000 bu simmetrik 蓹sas alqoritml蓹ri kimi. 73 00:02:36,000 --> 00:02:39,000 M蓹n RSA 艧ifreleme istifad蓹 ed蓹r蓹k mesaj g枚nd蓹rm蓹k ist蓹diyiniz Bel蓹 ki, 蓹g蓹r 74 00:02:39,000 --> 00:02:42,000 Rob, m蓹n ilk Rob ictimai 蓹sas laz谋md谋r. 75 00:02:42,000 --> 00:02:47,000 D眉ym蓹l蓹ri bir c眉t yaratmaq 眉莽眉n, Rob 2 b枚y眉k ba艧 n枚mr蓹l蓹ri y谋臒maq laz谋md谋r. 76 00:02:47,000 --> 00:02:50,000 Bu n枚mr蓹l蓹r, h蓹m d蓹 d枚vl蓹t v蓹 枚z蓹l a莽arlar谋 istifad蓹 olunacaq 77 00:02:50,000 --> 00:02:54,000 lakin ictimai 蓹sas yaln谋z bu 2 蓹d蓹d m蓹hsul istifad蓹 ed蓹c蓹k 78 00:02:54,000 --> 00:02:56,000 deyil n枚mr蓹l蓹ri 枚zl蓹ri. 79 00:02:56,000 --> 00:02:59,000 M蓹n Rob ictimai 蓹sas istifad蓹 ed蓹r蓹k mesaj 艧ifrelenir sonra 80 00:02:59,000 --> 00:03:01,000 M蓹n Rob mesaj g枚nd蓹r蓹 bil蓹rsiniz. 81 00:03:01,000 --> 00:03:05,000 Bir komp眉ter 眉莽眉n, faktorinq 蓹d蓹d a臒谋r problemdir. 82 00:03:05,000 --> 00:03:09,000 Ictimai 蓹sas, xat谋rlay谋ram, 2 ba艧 n枚mr蓹l蓹ri m蓹hsul istifad蓹. 83 00:03:09,000 --> 00:03:12,000 Bu m蓹hsul, sonra yaln谋z 2 amill蓹r olmal谋d谋r 84 00:03:12,000 --> 00:03:16,000 枚z蓹l 蓹sas t蓹艧kil ed蓹n n枚mr蓹l蓹ri olmaq 眉莽眉n ba艧 verir. 85 00:03:16,000 --> 00:03:20,000 Decrypt mesaj 眉莽眉n, RSA bu x眉susi a莽ar谋 istifad蓹 ed蓹c蓹k 86 00:03:20,000 --> 00:03:25,000 v蓹 ya 蓹d蓹d ictimai 蓹sas yarad谋lmas谋 prosesi birlikd蓹 vurulur. 87 00:03:25,000 --> 00:03:28,000 Bu say谋 Factor computationally 莽蓹tindir, 莽眉nki 88 00:03:28,000 --> 00:03:32,000 枚z蓹l 蓹sas istifad蓹 2 蓹d蓹d bir ictimai 蓹sas istifad蓹 89 00:03:32,000 --> 00:03:36,000 Bir sald谋rgan谋n 枚z蓹l 蓹sas anlamaq 眉莽眉n 莽蓹tin 90 00:03:36,000 --> 00:03:39,000 decrypt mesaj laz谋m olacaq. 91 00:03:39,000 --> 00:03:43,000 陌ndi RSA b蓹zi a艧a臒谋 t蓹f蓹rr眉ata varmaq bildirin. 92 00:03:43,000 --> 00:03:46,000 G蓹lin ilk biz d眉ym蓹l蓹ri bir c眉t yarada nec蓹. 93 00:03:46,000 --> 00:03:49,000 Birincisi, 2 ba艧 n枚mr蓹l蓹ri laz谋md谋r. 94 00:03:49,000 --> 00:03:52,000 Biz bu 2 蓹d蓹d p v蓹 q z蓹ng ed蓹c蓹yik. 95 00:03:52,000 --> 00:03:56,000 Praktikada p v蓹 q, se莽in 眉莽眉n biz pseudorandomly yaradacaq 96 00:03:56,000 --> 00:03:59,000 sonra b枚y眉k sayda v蓹 m眉蓹yy蓹n bir test istifad蓹 v蓹 ya 97 00:03:59,000 --> 00:04:02,000 bu 蓹d蓹d y蓹qin ki, ba艧 var. 98 00:04:02,000 --> 00:04:05,000 Biz yen蓹 眉z蓹rind蓹 t蓹sad眉fi n枚mr蓹l蓹ri yaradan saxlaya bil蓹rsiniz 99 00:04:05,000 --> 00:04:08,000 biz istifad蓹 ed蓹 bil蓹rsiniz ki, 2 primes q蓹d蓹r. 100 00:04:08,000 --> 00:04:15,000 Burada p = 23 q = 43 se莽in bildirin. 101 00:04:15,000 --> 00:04:19,000 Praktikada, saxla, p v蓹 q daha n枚mr蓹l蓹ri olmal谋d谋r. 102 00:04:19,000 --> 00:04:22,000 Bizd蓹 kimi, 蓹d蓹d b枚y眉k, daha bu 103 00:04:22,000 --> 00:04:25,000 艧ifreli mesaj谋 莽at. 104 00:04:25,000 --> 00:04:29,000 Lakin bu da 艧ifrelemek v蓹 decrypt mesaj daha bahal谋. 105 00:04:29,000 --> 00:04:33,000 Bu g眉n tez-tez p v蓹 q az谋 1024 bit olan t枚vsiy蓹, 106 00:04:33,000 --> 00:04:37,000 olan 300-d蓹n art谋q decimal r蓹q蓹m h蓹r say谋 qoyur. 107 00:04:37,000 --> 00:04:40,000 Amma bu m蓹s蓹l蓹n bu ki莽ik n枚mr蓹l蓹ri y谋臒maq laz谋md谋r. 108 00:04:40,000 --> 00:04:43,000 陌ndi, 3-c眉 n枚mr蓹 almaq 眉莽眉n birlikd蓹 p v蓹 q 莽oxaltmaq olacaq 109 00:04:43,000 --> 00:04:45,000 biz n z蓹ng bil蓹rsiniz. 110 00:04:45,000 --> 00:04:55,000 Bizim halda, n = 23 989 = olan * 43. 111 00:04:55,000 --> 00:04:58,000 Biz = 989 n. 112 00:04:58,000 --> 00:05:02,000 Q il蓹 - 1 - Next biz p 莽oxaltmaq olacaq 1 113 00:05:02,000 --> 00:05:05,000 biz m arayaca冒媒m olan 4-c眉 say谋. almaq 114 00:05:05,000 --> 00:05:15,000 Bizim halda, m = 22 924 = olan * 42. 115 00:05:15,000 --> 00:05:18,000 Biz m = 924 var. 116 00:05:18,000 --> 00:05:22,000 陌ndi nisb蓹t蓹n ba艧 ki, bir s谋ra e laz谋md谋r m 117 00:05:22,000 --> 00:05:25,000 v蓹 m-d蓹n azd谋r. 118 00:05:25,000 --> 00:05:28,000 Iki 蓹d蓹d nisb蓹t蓹n ba艧 v蓹 ya coprime var 119 00:05:28,000 --> 00:05:33,000 h蓹m b蓹rab蓹r onlara ay谋ran yaln谋z m眉sb蓹t tam 1 olsun. 120 00:05:33,000 --> 00:05:37,000 E v蓹 m Ba艧qa s枚zl蓹, 蓹n b枚y眉k ortaq b枚l蓹n 121 00:05:37,000 --> 00:05:39,000 1 olmal谋d谋r. 122 00:05:39,000 --> 00:05:44,000 T蓹cr眉b蓹d蓹, bu, ba艧 say谋 65537 olmaq e yayg谋n 123 00:05:44,000 --> 00:05:48,000 kimi uzun kimi bu r蓹q蓹m m amil olmaz. 124 00:05:48,000 --> 00:05:53,000 Bizim d眉ym蓹l蓹ri, biz se莽ece臒iz e = 5 125 00:05:53,000 --> 00:05:57,000 5 ild蓹n 924 il蓹 nisb蓹t蓹n ba艧 deyil. 126 00:05:57,000 --> 00:06:01,000 N蓹hay蓹t, biz d arayaca冒媒m daha bir say谋, laz谋md谋r. 127 00:06:01,000 --> 00:06:11,000 D t蓹nlik cavab ver蓹n b蓹zi d蓹y蓹ri olmal谋d谋r de = 1 (mod m). 128 00:06:11,000 --> 00:06:17,000 Bu mod m biz modul hesab deyil蓹n bir 艧ey istifad蓹 ed蓹c蓹yik bildirir. 129 00:06:17,000 --> 00:06:21,000 Modul hesab, bir bir s谋ra b蓹zi yuxar谋 ba臒l谋 daha y眉ks蓹k olur 130 00:06:21,000 --> 00:06:24,000 o 0 蓹traf谋nda geri paketi olacaq. 131 00:06:24,000 --> 00:06:27,000 A saat, m蓹s蓹l蓹n, modul hesab edir. 132 00:06:27,000 --> 00:06:31,000 1:59 sonra bir d蓹qiq蓹, m蓹s蓹l蓹n, 2:00 edir 133 00:06:31,000 --> 00:06:33,000 1:60 deyil. 134 00:06:33,000 --> 00:06:36,000 Bu d蓹qiq蓹 t蓹r蓹fd蓹n 0 蓹traf谋nda b眉k眉lm眉艧 edib 135 00:06:36,000 --> 00:06:39,000 60 ba臒l谋 bir 眉st 莽atd谋qda. 136 00:06:39,000 --> 00:06:46,000 Bel蓹 ki, 60 0 (mod 60) b蓹rab蓹rdir dem蓹k olar 137 00:06:46,000 --> 00:06:57,000 v蓹 125 65 b蓹rab蓹rdir 5 (mod 60) b蓹rab蓹rdir. 138 00:06:57,000 --> 00:07:02,000 Bizim ictimai 蓹sas c眉t e v蓹 n olacaq 139 00:07:02,000 --> 00:07:09,000 bu halda e 5 v蓹 n 989 edir. 140 00:07:09,000 --> 00:07:15,000 Bizim x眉susi d眉ym蓹si, c眉t d v蓹 n olacaq 141 00:07:15,000 --> 00:07:22,000 bizim halda olan 185 v蓹 989-dir. 142 00:07:22,000 --> 00:07:25,000 Orijinal primes p v蓹 q g枚r眉nm眉r ed蓹k ki, 143 00:07:25,000 --> 00:07:29,000 h蓹r yerd蓹 bizim 枚z蓹l v蓹 ya ictimai d眉ym蓹l蓹ri il蓹. 144 00:07:29,000 --> 00:07:33,000 陌ndi a莽arlar谋 bizim c眉t ki, biz 艧ifrelemek nec蓹 n蓹z蓹r ed蓹k 145 00:07:33,000 --> 00:07:36,000 v蓹 decrypt bir mesaj. 146 00:07:36,000 --> 00:07:38,000 M蓹n, Rob bir mesaj g枚nd蓹rm蓹k ist蓹yir蓹m 147 00:07:38,000 --> 00:07:42,000 o bu 蓹sas c眉t yaratmaq 眉莽眉n biri olacaq. 148 00:07:42,000 --> 00:07:46,000 Sonra m蓹n istifad蓹 ed蓹c蓹yik onun ictimai d眉ym蓹si 眉莽眉n Rob isteyece臒iz 149 00:07:46,000 --> 00:07:48,000 ona g枚nd蓹rm蓹k 眉莽眉n mesaj 艧ifrelemek. 150 00:07:48,000 --> 00:07:53,000 Rob m蓹n蓹 onun ictimai 蓹sas b枚l眉艧m蓹k 眉莽眉n Unutmay谋n, tamamil蓹 OK. 151 00:07:53,000 --> 00:07:56,000 Amma 枚z 艧蓹xsi 蓹sas b枚l眉艧m蓹k tamam olmaz. 152 00:07:56,000 --> 00:08:00,000 M蓹n onun x眉susi a莽ar谋 n蓹 he莽 bir fikir yoxdur. 153 00:08:00,000 --> 00:08:03,000 Biz bir ne莽蓹 chunks bizim mesaj m q蓹d蓹r q谋ra bil蓹r 154 00:08:03,000 --> 00:08:07,000 b眉t眉n sonra n daha ki莽ik v蓹 o chunks h蓹r 艧ifrelemek. 155 00:08:07,000 --> 00:08:12,000 Biz 4 chunks q蓹d蓹r q谋ra bil蓹r string CS50, 艧ifrelemek laz谋md谋r 156 00:08:12,000 --> 00:08:14,000 m蓹ktub ba艧谋na bir. 157 00:08:14,000 --> 00:08:17,000 M蓹nim mesaj 艧ifrelemek 眉莽眉n, m蓹n 莽evirm蓹k laz谋md谋r 158 00:08:17,000 --> 00:08:20,000 r蓹q蓹mli n眉may蓹nd蓹liyinin bir n枚v. 159 00:08:20,000 --> 00:08:25,000 Nin m蓹nim mesaj simvol il蓹 ASCII d蓹y蓹rl蓹r concatenate ed蓹k. 160 00:08:25,000 --> 00:08:28,000 Bir mesaj m 艧ifrelemek 眉莽眉n 161 00:08:28,000 --> 00:08:37,000 M蓹n e (mod n) c = m hesablamaq laz谋md谋r. 162 00:08:37,000 --> 00:08:40,000 Amma m, n daha ki莽ik olmal谋d谋r 163 00:08:40,000 --> 00:08:45,000 v蓹 ya ba艧qa tam mesaj modulo n ifad蓹 edil蓹 bilm蓹z. 164 00:08:45,000 --> 00:08:49,000 Biz n daha ki莽ik olan bir ne莽蓹 chunks, daxil m q蓹d蓹r q谋ra bil蓹r 165 00:08:49,000 --> 00:08:52,000 v蓹 bu chunks h蓹r 艧ifrelemek. 166 00:08:52,000 --> 00:09:03,000 Bu chunks h蓹r 艦ifreleme, biz almaq c1 olan 5 = 67 (MOD 989) 167 00:09:03,000 --> 00:09:06,000 hans谋 = 658. 168 00:09:06,000 --> 00:09:15,000 Ikinci y谋臒谋n biz 5 (MOD 989) 83 m枚vcut 169 00:09:15,000 --> 00:09:18,000 hans谋 = 15. 170 00:09:18,000 --> 00:09:26,000 脺莽眉nc眉 y谋臒谋n biz 5 (MOD 989) 53 m枚vcut 171 00:09:26,000 --> 00:09:30,000 hans谋 = 799. 172 00:09:30,000 --> 00:09:39,000 V蓹 n蓹hay蓹t, sonuncu y谋臒谋n biz 5 (MOD 989) 48 m枚vcut 173 00:09:39,000 --> 00:09:43,000 olan 975 =. 174 00:09:43,000 --> 00:09:48,000 陌ndi Rob bu 艧ifr蓹li d蓹y蓹rl蓹r g枚nd蓹r蓹 bil蓹rsiniz. 175 00:09:54,000 --> 00:09:58,000 Burada, Rob gedin. 176 00:09:58,000 --> 00:10:01,000 Bizim mesaj u莽u艧 olsa, g蓹lin bir n蓹z蓹r ed蓹k 177 00:10:01,000 --> 00:10:07,000 nec蓹 ki, biz d 眉莽眉n d蓹y蓹ri var. 178 00:10:07,000 --> 00:10:17,000 Bizim say谋 d 5d = 1 (MOD 924) t蓹min etm蓹k laz谋md谋r. 179 00:10:17,000 --> 00:10:24,000 Bu d 5 modulo 924 v蓹 multiplikativ t蓹rs edir. 180 00:10:24,000 --> 00:10:28,000 2 integers, bir v蓹 b, uzad谋lm谋艧 Evklid alqoritmi n蓹z蓹r蓹 alaraq 181 00:10:28,000 --> 00:10:33,000 Bu 2 integers 蓹n b枚y眉k ortaq b枚l蓹n tapmaq 眉莽眉n istifad蓹 edil蓹 bil蓹r. 182 00:10:33,000 --> 00:10:37,000 Bu da bizim dig蓹r 2 蓹d蓹d, x v蓹 y, ver蓹c蓹k 183 00:10:37,000 --> 00:10:47,000 bir v蓹 b = b枚y眉k ortaq b枚l蓹n t蓹r蓹find蓹n t蓹nlik balta + qane. 184 00:10:47,000 --> 00:10:49,000 Bu biz蓹 k枚m蓹k edir? 185 00:10:49,000 --> 00:10:52,000 Yax艧谋, bir 眉莽眉n e = 5 sayede 186 00:10:52,000 --> 00:10:56,000 v蓹 b m = 924 187 00:10:56,000 --> 00:10:59,000 biz art谋q bu r蓹q蓹ml蓹r coprime oldu臒unu bilir蓹m. 188 00:10:59,000 --> 00:11:03,000 Onlar谋n b枚y眉k ortaq b枚l蓹n 1-dir. 189 00:11:03,000 --> 00:11:09,000 Bu + 924y = 1 Bookmark 5x verir 190 00:11:09,000 --> 00:11:17,000 v蓹 ya 5x = 1 - 924y. 191 00:11:17,000 --> 00:11:22,000 Amma biz yaln谋z h蓹r 艧ey modulo 924 qay臒谋 蓹g蓹r 192 00:11:22,000 --> 00:11:25,000 924y - onda biz a莽谋l谋r. 193 00:11:25,000 --> 00:11:27,000 Saat geri d眉艧眉n眉n. 194 00:11:27,000 --> 00:11:31,000 D蓹qiq蓹 蓹l 1 v蓹 sonra tam 10 saat, 枚t眉rm蓹k edin 195 00:11:31,000 --> 00:11:35,000 biz d蓹qiq蓹 t蓹r蓹fd蓹n h蓹l蓹 1 olacaq bilirik. 196 00:11:35,000 --> 00:11:39,000 Burada, 1-d蓹 ba艧layacaq v蓹 sonra d蓹qiq y d蓹f蓹 蓹traf谋nda kesmek 197 00:11:39,000 --> 00:11:41,000 biz h蓹l蓹 1 olacaq. 198 00:11:41,000 --> 00:11:49,000 Biz = 1 (MOD 924) 5x var. 199 00:11:49,000 --> 00:11:55,000 V蓹 burada x, biz 蓹vv蓹l arad谋臒谋n谋z d eyni 200 00:11:55,000 --> 00:11:58,000 Biz uzun Evklid alqoritmi istifad蓹 蓹g蓹r 201 00:11:58,000 --> 00:12:04,000 bu say谋 x almaq ki, biz d kimi istifad蓹 etm蓹lidir say谋 var. 202 00:12:04,000 --> 00:12:07,000 陌ndi bir = 5 uzad谋lm谋艧 Evklid alqoritmi run bildirin 203 00:12:07,000 --> 00:12:11,000 v蓹 b = 924. 204 00:12:11,000 --> 00:12:14,000 Biz masa metodu deyil蓹n bir 眉sul istifad蓹 ed蓹c蓹yik. 205 00:12:14,000 --> 00:12:21,000 Bizim masa 4 s眉tun, x, y, d, v蓹 k olacaq. 206 00:12:21,000 --> 00:12:23,000 Bizim c蓹dv蓹l 2 sat谋r il蓹 off ba艧lay谋r. 207 00:12:23,000 --> 00:12:28,000 Ilk s谋rada biz sonra 1, 0, 5 olan bizim d蓹y蓹ri var, 208 00:12:28,000 --> 00:12:37,000 v蓹 ikinci s谋ra 0, 1 v蓹 b 眉莽眉n d蓹y蓹ri olan 924-dir. 209 00:12:37,000 --> 00:12:40,000 4-c眉 s眉tun, k, d蓹y蓹ri n蓹tic蓹 olacaq 210 00:12:40,000 --> 00:12:45,000 d d蓹y蓹ri il蓹 yuxar谋da s谋ras谋nda d d蓹y蓹ri ay谋r谋c谋 il蓹 211 00:12:45,000 --> 00:12:49,000 eyni s谋rada. 212 00:12:49,000 --> 00:12:56,000 Biz 924 b枚l眉n眉r 5 b蓹zi qalan 0 var. 213 00:12:56,000 --> 00:12:59,000 Y蓹ni = 0 k var dem蓹kdir. 214 00:12:59,000 --> 00:13:05,000 陌ndi h蓹r bir dig蓹r mobil d蓹y蓹ri yuxar谋da mobil 2 sat谋r d蓹y蓹ri olacaq 215 00:13:05,000 --> 00:13:09,000 bu d蓹f蓹 k yuxar谋da s谋ra m蓹nfi d蓹y蓹r. 216 00:13:09,000 --> 00:13:11,000 3-c眉 s谋ra d ba艧lamaq ed蓹k. 217 00:13:11,000 --> 00:13:19,000 Biz 5 var - 924 * 0 = 5. 218 00:13:19,000 --> 00:13:25,000 0 olan 1 * 0 - 0 biz var Sonraki 219 00:13:25,000 --> 00:13:30,000 v蓹 1 - 0 * 0, 1-dir. 220 00:13:30,000 --> 00:13:33,000 脟ox pis deyil, bel蓹 ki, bu v蓹 n枚vb蓹ti s谋raya h蓹r蓹k蓹t ed蓹k. 221 00:13:33,000 --> 00:13:36,000 陌lk k bizim d蓹y蓹r laz谋md谋r. 222 00:13:36,000 --> 00:13:43,000 924, b蓹zi qalan 5 = 184 b枚l眉n眉r 223 00:13:43,000 --> 00:13:46,000 bel蓹 k 眉莽眉n d蓹y蓹r 184-dir. 224 00:13:46,000 --> 00:13:54,000 陌ndi 924 - 5 * 184 = 4. 225 00:13:54,000 --> 00:14:05,000 1 - 0 * 184 1 v蓹 0 - 1 * 184 -184 edir. 226 00:14:05,000 --> 00:14:07,000 B眉t眉n h眉quqlar, n枚vb蓹ti s谋ra n蓹 ed蓹k. 227 00:14:07,000 --> 00:14:10,000 K Bizim d蓹y蓹ri 1 莽眉nki olacaq 228 00:14:10,000 --> 00:14:15,000 5 b蓹zi qalan 4 = 1 b枚l眉n眉r. 229 00:14:15,000 --> 00:14:17,000 Nin dig蓹r s眉tunlar doldurmaq ed蓹k. 230 00:14:17,000 --> 00:14:21,000 5 - 4 * 1 = 1. 231 00:14:21,000 --> 00:14:25,000 0 - 1 * 1 = -1. 232 00:14:25,000 --> 00:14:33,000 V蓹 1 - 184 * 1 185-dir. 233 00:14:33,000 --> 00:14:35,000 K n枚vb蓹ti d蓹y蓹r ola bil蓹r n蓹 ed蓹k. 234 00:14:35,000 --> 00:14:40,000 Biz 4 olan 1, 4 b枚l眉n眉r var kimi B蓹li, g枚r眉n眉r. 235 00:14:40,000 --> 00:14:43,000 Biz 1-ay谋r谋c谋 oldu臒unuz Bu halda, bel蓹 ki, k b蓹rab蓹rdir 236 00:14:43,000 --> 00:14:50,000 Yuxar谋da s谋ra d d蓹y蓹ri bizim alqoritmi il蓹 tamamlay谋n dem蓹kdir. 237 00:14:50,000 --> 00:14:58,000 Biz son s谋rada x = 185 v蓹 y = -1 ki, burada g枚r蓹 bil蓹rsiniz. 238 00:14:58,000 --> 00:15:00,000 Indi bizim orijinal m蓹qs蓹di qay谋tmaq ed蓹k. 239 00:15:00,000 --> 00:15:04,000 Biz n蓹tic蓹sind蓹 x d蓹y蓹ri bu alqoritm 莽al谋艧an bildirib ki, 240 00:15:04,000 --> 00:15:08,000 a (mod b) multiplikativ t蓹rs olard谋. 241 00:15:08,000 --> 00:15:15,000 Bu 185 5 multiplikativ t蓹rs (MOD 924) dem蓹kdir 242 00:15:15,000 --> 00:15:20,000 olan biz d 185 bir d蓹y蓹ri dem蓹kdir. 243 00:15:20,000 --> 00:15:23,000 Olmas谋 d = 1 son s谋rada 244 00:15:23,000 --> 00:15:26,000 e m coprime edilib do臒rular. 245 00:15:26,000 --> 00:15:30,000 1 deyil 茝g蓹r biz yeni bir e se莽in olard谋. 246 00:15:30,000 --> 00:15:33,000 陌ndi Rob m蓹nim mesaj谋 蓹g蓹r in g枚r蓹k. 247 00:15:33,000 --> 00:15:35,000 Kims蓹 m蓹n蓹 bir 艧ifr蓹li mesaj g枚nd蓹rir zaman 248 00:15:35,000 --> 00:15:38,000 kimi uzun M蓹n x眉susi a莽ar谋 gizli saxlan谋l谋r oldu臒unuz kimi 249 00:15:38,000 --> 00:15:41,000 M蓹n kim mesaj decrypt bil蓹r yaln谋z bir deyil蓹m. 250 00:15:41,000 --> 00:15:46,000 Decrypt bir y谋臒谋n c M蓹n orijinal mesaj谋 hesablamaq olar 251 00:15:46,000 --> 00:15:53,000 d g眉c眉 (mod n) 眉莽眉n y谋臒谋n b蓹rab蓹rdir. 252 00:15:53,000 --> 00:15:57,000 D v蓹 n m蓹nim x眉susi a莽ar谋 var unutmay谋n. 253 00:15:57,000 --> 00:16:01,000 Biz decrypt h蓹r y谋臒谋n onun chunks bir tam mesaj almaq 眉莽眉n 254 00:16:01,000 --> 00:16:04,000 v蓹 n蓹tic蓹l蓹ri concatenate. 255 00:16:04,000 --> 00:16:08,000 RSA M蓹hz nec蓹 t蓹hl眉k蓹siz? 256 00:16:08,000 --> 00:16:10,000 H蓹qiq蓹t, biz bilmirik. 257 00:16:10,000 --> 00:16:14,000 T蓹hl眉k蓹sizlik bir mesaj 莽at bir sald谋rgan谋n almaq nec蓹 uzun 蓹saslan谋r 258 00:16:14,000 --> 00:16:16,000 RSA il蓹 艧ifrelenir. 259 00:16:16,000 --> 00:16:19,000 Bir sald谋rgan谋n ictimai 蓹sas 莽谋x谋艧谋 var ki, saxla, 260 00:16:19,000 --> 00:16:21,000 e v蓹 n d蓹 var. 261 00:16:21,000 --> 00:16:26,000 T蓹cav眉zkar谋n 枚z 2 primes, p v蓹 q, daxil n amil idar蓹 edin 262 00:16:26,000 --> 00:16:30,000 sonra o, uzun Evklid alqoritmi istifad蓹 d hesablamaq bil蓹r. 263 00:16:30,000 --> 00:16:35,000 Bu onun h蓹r hans谋 bir mesaj谋 decrypt 眉莽眉n istifad蓹 edil蓹 bil蓹r olan 枚z蓹l 蓹sas verir. 264 00:16:35,000 --> 00:16:38,000 Amma nec蓹 tez biz integers amil ola bil蓹r? 265 00:16:38,000 --> 00:16:41,000 Yen蓹 bilmir蓹m. 266 00:16:41,000 --> 00:16:43,000 He莽 k蓹s bunu bir s眉r蓹tli yol tapd谋 267 00:16:43,000 --> 00:16:46,000 hans谋 verilmi艧 o dem蓹kdir ki, kifay蓹t q蓹d蓹r b枚y眉k n 268 00:16:46,000 --> 00:16:49,000 bu unrealistically uzun bir sald谋rgan谋n ed蓹c蓹k 269 00:16:49,000 --> 00:16:51,000 say谋 amil 眉莽眉n. 270 00:16:51,000 --> 00:16:54,000 Kims蓹 faktorinq integers bir s眉r蓹tli yol a艧kar edin 271 00:16:54,000 --> 00:16:57,000 RSA s谋n谋q olard谋. 272 00:16:57,000 --> 00:17:01,000 Lakin, h蓹tta tam factorization mahiyy蓹t yava艧 273 00:17:01,000 --> 00:17:04,000 RSA alqoritmi, h蓹l蓹 d蓹 b蓹zi q眉sur ola bil蓹r 274 00:17:04,000 --> 00:17:07,000 mesajlar asan parol 莽枚zme 眉莽眉n imkan verir. 275 00:17:07,000 --> 00:17:10,000 He莽 k蓹s, h蓹l蓹 bel蓹 bir q眉sur a艧kar v蓹 a艧kar 276 00:17:10,000 --> 00:17:12,000 lakin bir m枚vcud deyil dem蓹k deyil. 277 00:17:12,000 --> 00:17:17,000 N蓹z蓹ri olaraq, kims蓹 RSA il蓹 艧ifrelenir b眉t眉n m蓹lumatlar谋 oxumaq orada ola bil蓹r. 278 00:17:17,000 --> 00:17:19,000 Bir gizlilik m蓹s蓹l蓹nin ba艧qa bit var. 279 00:17:19,000 --> 00:17:23,000 Tommy m蓹nim ictimai a莽ar谋 istifad蓹 bir mesaj 艧ifreleyerek edin 280 00:17:23,000 --> 00:17:26,000 v蓹 t蓹cav眉zkar m蓹nim ictimai 蓹sas istifad蓹 ed蓹r蓹k eyni mesaj 艧ifreleyerek 281 00:17:26,000 --> 00:17:29,000 t蓹cav眉zkar谋n 2 mesaj eyni oldu臒unu g枚r蓹c蓹ksiniz 282 00:17:29,000 --> 00:17:32,000 v蓹 bel蓹likl蓹 Tommy 艧ifrelenir bilirik. 283 00:17:32,000 --> 00:17:36,000 Bu qar艧谋s谋n谋 almaq 眉莽眉n, mesajlar ad蓹t蓹n t蓹sad眉fi bit il蓹 padded olunur 284 00:17:36,000 --> 00:17:39,000 eyni mesaj 艧ifr蓹l蓹nir ki 艧ifrelenir 蓹vv蓹l 285 00:17:39,000 --> 00:17:44,000 Mesaj 眉zr蓹 padding f蓹rqli olaraq bird蓹n 莽ox uzun kimi m眉xt蓹lif g枚r眉n眉r. 286 00:17:44,000 --> 00:17:47,000 Amma biz chunks daxil messages split nec蓹 yadda 287 00:17:47,000 --> 00:17:50,000 h蓹r y谋臒谋n n daha ki莽ik ki? 288 00:17:50,000 --> 00:17:52,000 Bu chunks padding biz 艧eyi split ola bil蓹r o dem蓹kdir ki, 289 00:17:52,000 --> 00:17:57,000 ild蓹n daha chunks daxil padded y谋臒谋n n daha ki莽ik olmal谋d谋r. 290 00:17:57,000 --> 00:18:01,000 艦ifr蓹l蓹m蓹 v蓹 parol 莽枚zme, RSA il蓹 nisb蓹t蓹n bahal谋 291 00:18:01,000 --> 00:18:05,000 v蓹 bir 莽ox chunks bir mesaj par莽alamaq ehtiyac 莽ox bahal谋 ola bil蓹r. 292 00:18:05,000 --> 00:18:09,000 M蓹lumatlar谋n b枚y眉k h蓹cmd蓹 艧ifr蓹li olmal谋d谋r v蓹 艧ifresi 莽枚z眉len edin 293 00:18:09,000 --> 00:18:12,000 biz simmetrik 蓹sas alqoritml蓹ri faydalar谋 birl蓹艧dir蓹 bil蓹r 294 00:18:12,000 --> 00:18:16,000 RSA bu t蓹hl眉k蓹sizlik v蓹 s蓹m蓹r蓹lilik h蓹m almaq 眉莽眉n. 295 00:18:16,000 --> 00:18:18,000 Biz burada daxil deyil baxmayaraq, 296 00:18:18,000 --> 00:18:23,000 AES bu Vigen猫re v蓹 Caesar ciphers kimi bir simmetrik 蓹sas alqoritm edir 297 00:18:23,000 --> 00:18:25,000 amma 莽ox 莽蓹tindir 莽at. 298 00:18:25,000 --> 00:18:30,000 茝lb蓹tt蓹 ki, biz ortaq bir gizli 蓹sas yaratmadan AES istifad蓹 ed蓹 299 00:18:30,000 --> 00:18:34,000 2-sisteml蓹ri aras谋nda, biz 蓹vv蓹l problem g枚rd眉m. 300 00:18:34,000 --> 00:18:40,000 Amma indi biz 2-sisteml蓹ri aras谋nda payla艧谋lan gizli 蓹sas yaratmaq RSA istifad蓹 ed蓹 bil蓹rsiniz. 301 00:18:40,000 --> 00:18:43,000 Biz data g枚nd蓹r蓹n g枚nd蓹rilm蓹si komp眉ter arayaca冒媒m 302 00:18:43,000 --> 00:18:46,000 v蓹 komp眉ter data al谋c谋 al谋nmas谋. 303 00:18:46,000 --> 00:18:49,000 Al谋c谋 bir RSA 蓹sas c眉t v蓹 g枚nd蓹rir 304 00:18:49,000 --> 00:18:51,000 g枚nd蓹r蓹n ictimai d眉ym蓹si. 305 00:18:51,000 --> 00:18:54,000 G枚nd蓹r蓹n bir AES 蓹sas yarad谋r 306 00:18:54,000 --> 00:18:57,000 al谋c谋-nin RSA ictimai 蓹sas il蓹 艧ifreleyerek, 307 00:18:57,000 --> 00:19:00,000 v蓹 al谋c谋 眉莽眉n AES 蓹sas g枚nd蓹rir. 308 00:19:00,000 --> 00:19:04,000 Al谋c谋 枚z RSA 艦蓹xsi d眉ym蓹sind蓹n il蓹 mesaj 艧ifrini a莽谋r. 309 00:19:04,000 --> 00:19:09,000 G枚nd蓹r蓹n v蓹 al谋c谋, h蓹m d蓹 indi onlar谋n aras谋nda ortaq bir AES 蓹sas var. 310 00:19:09,000 --> 00:19:14,000 RSA 莽ox 艧ifr蓹l蓹m蓹 v蓹 parol 莽枚zme da 莽ox daha s眉r蓹tli olan AES, 311 00:19:14,000 --> 00:19:18,000 indi m蓹lumatlar谋n b枚y眉k h蓹cmd蓹 艧ifrelemek v蓹 al谋c谋 onlar谋 g枚nd蓹rm蓹k 眉莽眉n istifad蓹 edil蓹 bil蓹r, 312 00:19:18,000 --> 00:19:21,000 decrypt h蓹min 蓹sas olan istifad蓹 ed蓹 bil蓹rsiniz. 313 00:19:21,000 --> 00:19:26,000 RSA 莽ox 艧ifr蓹l蓹m蓹 v蓹 parol 莽枚zme da 莽ox daha s眉r蓹tli olan AES, 314 00:19:26,000 --> 00:19:30,000 indi m蓹lumatlar谋n b枚y眉k h蓹cmd蓹 艧ifrelemek v蓹 al谋c谋 onlar谋 g枚nd蓹rm蓹k 眉莽眉n istifad蓹 edil蓹 bil蓹r, 315 00:19:30,000 --> 00:19:32,000 decrypt h蓹min 蓹sas olan istifad蓹 ed蓹 bil蓹rsiniz. 316 00:19:32,000 --> 00:19:36,000 Biz yaln谋z payla艧谋lan 蓹sas transfer RSA laz谋md谋r. 317 00:19:36,000 --> 00:19:40,000 Biz art谋q b眉t眉n RSA istifad蓹 etm蓹k laz谋md谋r. 318 00:19:40,000 --> 00:19:46,000 M蓹n bir mesaj var kimi g枚r眉n眉r. 319 00:19:46,000 --> 00:19:49,000 H蓹r ka臒谋z t蓹yyar蓹 var n蓹 oxumaq 蓹g蓹r m蓹n tutdu 蓹vv蓹l etm蓹z 320 00:19:49,000 --> 00:19:55,000 M蓹n x眉susi a莽ar il蓹 yaln谋z bir deyil蓹m, 莽眉nki. 321 00:19:55,000 --> 00:19:57,000 Iletideki chunks h蓹r decrypt ed蓹k. 322 00:19:57,000 --> 00:20:07,000 Ilk y谋臒谋n, 658, biz 185 olan d enerji il蓹 qald谋rmaq 323 00:20:07,000 --> 00:20:18,000 989 olan mod n, 67-蓹 b蓹rab蓹rdir 324 00:20:18,000 --> 00:20:24,000 ASCII-ci m蓹ktub C-dir. 325 00:20:24,000 --> 00:20:31,000 陌ndi, ikinci y谋臒谋n daxil. 326 00:20:31,000 --> 00:20:35,000 陌kinci y谋臒谋n, d蓹y蓹ri 15 var 327 00:20:35,000 --> 00:20:41,000 biz 185th hakimiyy蓹t蓹 qald谋rmaq olan 328 00:20:41,000 --> 00:20:51,000 mod 989, v蓹 bu 83-蓹 b蓹rab蓹rdir 329 00:20:51,000 --> 00:20:57,000 ASCII-ci m蓹ktub S olan. 330 00:20:57,000 --> 00:21:06,000 陌ndi d蓹y蓹ri 799 olan 眉莽眉nc眉 y谋臒谋n 眉莽眉n, biz 185 qald谋rmaq 331 00:21:06,000 --> 00:21:17,000 mod 989, v蓹 bu 53-蓹 b蓹rab蓹rdir, 332 00:21:17,000 --> 00:21:24,000 ASCII-ci karakter 5 d蓹y蓹ri olan. 333 00:21:24,000 --> 00:21:30,000 陌ndi son y谋臒谋n 眉莽眉n olan d蓹y蓹ri 975 var 334 00:21:30,000 --> 00:21:41,000 biz 185 mod 989, qald谋rmaq 335 00:21:41,000 --> 00:21:51,000 v蓹 bu ASCII ild蓹 karakter 0 d蓹y蓹ri olan 48, b蓹rab蓹rdir. 336 00:21:51,000 --> 00:21:57,000 My name Rob Bowden, bu CS50 edir. 337 00:21:57,000 --> 00:22:00,000 [CS50.TV] 338 00:22:06,000 --> 00:22:08,000 B眉t眉n RSA. 339 00:22:08,000 --> 00:22:14,000 B眉t眉n RSA. [G眉l眉艧] 340 00:22:14,000 --> 00:22:17,000 B眉t眉n.