1 00:00:00,000 --> 00:00:01,310 So first, an overview of 2 00:00:01,310 --> 00:00:02,540 encryption mechanism. 3 00:00:02,540 --> 00:00:03,713 And the first one is going to be 4 00:00:03,713 --> 00:00:05,580 encryption in flights. 5 00:00:05,580 --> 00:00:08,070 Then, why would we want even encryption in flights? 6 00:00:08,070 --> 00:00:09,520 Well, we want encryption in flight because 7 00:00:09,520 --> 00:00:11,810 if I send a very sensitive secret, 8 00:00:11,810 --> 00:00:14,710 for example, my credit card to a server, 9 00:00:14,710 --> 00:00:16,329 to make a payment online, 10 00:00:16,329 --> 00:00:19,060 I want to make sure that no one else, on the way, 11 00:00:19,060 --> 00:00:21,770 where my network packet is going to travel, 12 00:00:21,770 --> 00:00:23,740 can see my credit card number. 13 00:00:23,740 --> 00:00:24,670 So I want to make sure that 14 00:00:24,670 --> 00:00:26,240 when I make a payment online, 15 00:00:26,240 --> 00:00:27,500 I have that green lock, 16 00:00:27,500 --> 00:00:30,500 I have that HTTPS website which guarantees me, 17 00:00:30,500 --> 00:00:32,360 that it is an SSL enabled website, 18 00:00:32,360 --> 00:00:34,160 and I will get encryption in flight. 19 00:00:34,160 --> 00:00:35,670 And so when you have encryption in flight, 20 00:00:35,670 --> 00:00:36,830 the data will be encrypted 21 00:00:36,830 --> 00:00:38,200 before I sent it, 22 00:00:38,200 --> 00:00:40,470 and then the server will be decrypting it 23 00:00:40,470 --> 00:00:41,800 after receiving it. 24 00:00:41,800 --> 00:00:43,510 But, only myself and the server 25 00:00:43,510 --> 00:00:45,440 know how to do these things. 26 00:00:45,440 --> 00:00:48,190 Now the SSL certificates are what's going to 27 00:00:48,190 --> 00:00:50,990 help with the encryption, and so another way to 28 00:00:50,990 --> 00:00:52,660 see it is HTTPS. 29 00:00:52,660 --> 00:00:53,960 So anytime we've been dealing 30 00:00:53,960 --> 00:00:55,440 with with an Amazon service, 31 00:00:55,440 --> 00:00:57,570 and it had an HTTPS endpoint, 32 00:00:57,570 --> 00:00:59,910 that guaranteed us that it was encryption in flight. 33 00:00:59,910 --> 00:01:02,050 And now the whole web, almost the whole web, 34 00:01:02,050 --> 00:01:04,843 needs to run on SSL and HTTPS. 35 00:01:06,220 --> 00:01:08,330 Basically, when you have this enabled, 36 00:01:08,330 --> 00:01:09,760 you're protected against 37 00:01:09,760 --> 00:01:11,370 the 'man in the middle' attack. 38 00:01:11,370 --> 00:01:14,069 And so, this guarantees that, 39 00:01:14,069 --> 00:01:15,040 when you have that green lock, 40 00:01:15,040 --> 00:01:16,840 and that the server certificate is valid, 41 00:01:16,840 --> 00:01:19,940 that no one can retrieve your sensitive information. 42 00:01:19,940 --> 00:01:21,590 So let's do a quick example. 43 00:01:21,590 --> 00:01:23,130 Here is us, and we want to talk to 44 00:01:23,130 --> 00:01:25,270 an HTTP website on AWS; 45 00:01:25,270 --> 00:01:26,250 could be DynamoDB, 46 00:01:26,250 --> 00:01:27,760 could be whatever we want. 47 00:01:27,760 --> 00:01:28,880 And then what we're going to do, 48 00:01:28,880 --> 00:01:31,720 is that we're going to have add the super secret data, 49 00:01:31,720 --> 00:01:34,730 we're going to encrypt it with SSL encryption, 50 00:01:34,730 --> 00:01:36,440 and send it over the network, 51 00:01:36,440 --> 00:01:38,580 and then the website will receive the data, 52 00:01:38,580 --> 00:01:40,333 and know how to decrypt it. 53 00:01:41,180 --> 00:01:43,300 Very, very simple; the idea of it, 54 00:01:43,300 --> 00:01:44,690 but the execution is not as easy, 55 00:01:44,690 --> 00:01:46,520 so this is how much I'll give you. 56 00:01:46,520 --> 00:01:48,510 The good news is that all programming languages 57 00:01:48,510 --> 00:01:50,530 know how to do SSL encryption and decryption, 58 00:01:50,530 --> 00:01:52,230 and already do this for you, 59 00:01:52,230 --> 00:01:53,780 so you don't have to worry about anything. 60 00:01:53,780 --> 00:01:56,460 This is not something you have to deal with directly. 61 00:01:56,460 --> 00:01:58,030 The second thing is going to be called 62 00:01:58,030 --> 00:02:00,030 server side encryption at rest. 63 00:02:00,030 --> 00:02:03,000 And so that is when the data is encrypted, 64 00:02:03,000 --> 00:02:05,040 after being received by the server. 65 00:02:05,040 --> 00:02:07,350 So before that, the server was receiving data, 66 00:02:07,350 --> 00:02:09,479 decrypting it, and using it in its decrypted form. 67 00:02:09,479 --> 00:02:10,850 Here, the server is going to 68 00:02:10,850 --> 00:02:12,600 store the data on its disk, 69 00:02:12,600 --> 00:02:15,160 and so we need to know that the server 70 00:02:15,160 --> 00:02:17,950 is storing the data in an encrypted form. 71 00:02:17,950 --> 00:02:20,370 Because, in case the server gets hijacked 72 00:02:20,370 --> 00:02:21,203 by someone else, 73 00:02:21,203 --> 00:02:22,036 we don't want that someone else 74 00:02:22,036 --> 00:02:24,080 to be able to decrypt that data. 75 00:02:24,080 --> 00:02:27,310 And so the data will be decrypted before being sent 76 00:02:27,310 --> 00:02:29,410 back to our client. 77 00:02:29,410 --> 00:02:32,490 So, thanks to a key, usually called a data key, 78 00:02:32,490 --> 00:02:34,320 then that data is going to be stored 79 00:02:34,320 --> 00:02:35,566 in an encrypted form, 80 00:02:35,566 --> 00:02:37,780 and the encryption and decryption keys 81 00:02:37,780 --> 00:02:38,830 must be managed somewhere, 82 00:02:38,830 --> 00:02:41,640 usually called a KMS, or key management service, 83 00:02:41,640 --> 00:02:43,743 and the server must have the right to talk to 84 00:02:43,743 --> 00:02:45,750 that key management service. 85 00:02:45,750 --> 00:02:47,630 So here's our object, and we're going to 86 00:02:47,630 --> 00:02:49,780 transfer it, for example, to EBS. 87 00:02:49,780 --> 00:02:52,118 So it's gonna be transferred over whatever mechanism, 88 00:02:52,118 --> 00:02:54,720 and EBS will use a data key, 89 00:02:54,720 --> 00:02:58,510 and using a data key will perform encryption of that data, 90 00:02:58,510 --> 00:03:00,380 and now it's stored in an encrypted form, 91 00:03:00,380 --> 00:03:02,540 and then the day we need to retrieve the data 92 00:03:02,540 --> 00:03:04,930 for whatever reason, then EBS, 93 00:03:04,930 --> 00:03:06,860 the AWS service, will do decryption for us 94 00:03:06,860 --> 00:03:08,310 using the data key again, 95 00:03:08,310 --> 00:03:09,988 and we'll get the de-encrypted data, 96 00:03:09,988 --> 00:03:14,040 and back to us over at HTTP, HTTPS, for example. 97 00:03:14,040 --> 00:03:16,150 So this is how server side encryption works, 98 00:03:16,150 --> 00:03:18,480 and as you can see, the server side itself 99 00:03:18,480 --> 00:03:20,670 of the service, manages the encryption 100 00:03:20,670 --> 00:03:23,030 and the decryption, and uses a data key 101 00:03:23,030 --> 00:03:24,810 it has access to. 102 00:03:24,810 --> 00:03:27,170 So this is, for server side encryption at rest. 103 00:03:27,170 --> 00:03:29,830 And we've seen that many AWS services 104 00:03:29,830 --> 00:03:32,303 do use that encryption at rest. 105 00:03:33,450 --> 00:03:35,709 Now let's talk about client side encryption. 106 00:03:35,709 --> 00:03:37,480 In client side encryption, the data will be 107 00:03:37,480 --> 00:03:40,160 encrypted by the client, and the client is us. 108 00:03:40,160 --> 00:03:43,110 The server will never be able to decrypt that data. 109 00:03:43,110 --> 00:03:47,000 The data will then be decrypted by a receiving client. 110 00:03:47,000 --> 00:03:49,600 So all in all, the data is just stored on the server, 111 00:03:49,600 --> 00:03:51,930 but the server doesn't know what the data means. 112 00:03:51,930 --> 00:03:54,090 And the server, as best practice, 113 00:03:54,090 --> 00:03:57,210 should never be able to decrypt the data anyway. 114 00:03:57,210 --> 00:03:59,440 And for this, we could leverage something called 115 00:03:59,440 --> 00:04:02,350 envelope encryption, but I have a whole lecture on this 116 00:04:02,350 --> 00:04:04,170 later on, because this is pretty advanced, 117 00:04:04,170 --> 00:04:06,520 but the example asks you about envelope encryption, 118 00:04:06,520 --> 00:04:09,120 so for now, let's just do an abstraction of it. 119 00:04:09,120 --> 00:04:11,510 So we have our object, and on our client, 120 00:04:11,510 --> 00:04:13,890 we're going to use a data key, 121 00:04:13,890 --> 00:04:16,980 and we're going to encrypt our data client side. 122 00:04:16,980 --> 00:04:19,170 So we perform encryption with that data key. 123 00:04:19,170 --> 00:04:22,180 Now we send that data to any store of data we want; 124 00:04:22,180 --> 00:04:23,870 could be FTP, could be S3, 125 00:04:23,870 --> 00:04:25,660 could be whatever you want really. 126 00:04:25,660 --> 00:04:27,840 You put your data wherever you want, 127 00:04:27,840 --> 00:04:29,400 say Amazon or somewhere else. 128 00:04:29,400 --> 00:04:31,670 And then, when you receive it, 129 00:04:31,670 --> 00:04:34,860 your client will receive an encrypted object, 130 00:04:34,860 --> 00:04:37,690 and if it has access to the data key, 131 00:04:37,690 --> 00:04:38,930 if it can manage to retrieve 132 00:04:38,930 --> 00:04:40,980 the data key from somewhere, 133 00:04:40,980 --> 00:04:43,101 then it will be able to perform a decryption, 134 00:04:43,101 --> 00:04:46,250 and get the decrypted object as a result. 135 00:04:46,250 --> 00:04:48,240 So as you can see now, the encryption happens 136 00:04:48,240 --> 00:04:49,400 client side. 137 00:04:49,400 --> 00:04:51,830 The server, the data store, does not know how 138 00:04:51,830 --> 00:04:53,570 to decrypt or encrypt the data, 139 00:04:53,570 --> 00:04:55,940 it just receives encrypted data. 140 00:04:55,940 --> 00:04:57,590 And so that's quite secure as well. 141 00:04:57,590 --> 00:04:59,550 So here are the three kinds of encryption 142 00:04:59,550 --> 00:05:03,180 you can get, overall, except envelope encryption 143 00:05:03,180 --> 00:05:04,320 that we'll show you later on. 144 00:05:04,320 --> 00:05:08,270 So this is not using any KMS just yet. 145 00:05:08,270 --> 00:05:10,770 This is just an abstraction of how encryption works. 146 00:05:10,770 --> 00:05:12,320 I know this may be a little bit simplified, 147 00:05:12,320 --> 00:05:14,930 but hopefully that clears up what encryption is, 148 00:05:14,930 --> 00:05:16,460 and in the next lecture, we're going to 149 00:05:16,460 --> 00:05:18,093 do a deep dive into KMS.