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These are the user uploaded subtitles that are being translated: 1 00:00:00,310 --> 00:00:09,600 Fonzo go out tour now today is an open source anonymising encrypting volunteer operated proxy network 2 00:00:10,050 --> 00:00:17,250 tool helps to reduce the risks of both simple and sophisticated network analysis by distributing your 3 00:00:17,250 --> 00:00:24,660 Internet traffic over several lairs or relays on the Internet so no single point can link you to your 4 00:00:24,660 --> 00:00:25,830 destination. 5 00:00:26,010 --> 00:00:27,340 And that's as you can see here. 6 00:00:27,390 --> 00:00:33,420 This might be you and you're going over a number of relays before you get to your final destination 7 00:00:33,420 --> 00:00:33,890 . 8 00:00:34,190 --> 00:00:38,820 When stores installed it places a Sock's five proxy on your client. 9 00:00:38,820 --> 00:00:44,790 So if you install it on Windows you have a satisfied client on your Windows machine and when correctly 10 00:00:44,790 --> 00:00:45,920 configured. 11 00:00:46,320 --> 00:00:53,180 All designed Internet traffic can be made to go through that proxy so you can see here you would have 12 00:00:53,180 --> 00:00:59,340 a proxy on here and that would force all the traffic to go via this path here. 13 00:00:59,840 --> 00:01:05,820 Packets entering the proxy are encrypted and sent into the tonette where they afforded to another Tor 14 00:01:05,820 --> 00:01:13,560 node and another until finally reaching an exit node where the data is decrypted and sent to its final 15 00:01:13,560 --> 00:01:14,340 destination. 16 00:01:14,340 --> 00:01:21,650 For example Google dot com or Facebook and that full connection would be called a tor circuit and there 17 00:01:21,640 --> 00:01:23,660 is your exit node there. 18 00:01:23,670 --> 00:01:24,750 In addition to this. 19 00:01:24,810 --> 00:01:27,710 So that's using the surface web. 20 00:01:27,780 --> 00:01:38,970 You can also access what is called hidden services and these are accessible by these dot on you or else 21 00:01:39,030 --> 00:01:45,230 as you can see here which is essentially that you are able to access the Tor dot net an exit node. 22 00:01:45,390 --> 00:01:52,860 In this case isn't required what you'll do is instead of coming out of here and exiting to Facebook 23 00:01:52,860 --> 00:02:00,000 or wherever it is you're going you'll go to a server that is within it or network which means your traffic 24 00:02:00,000 --> 00:02:01,900 remains encrypted end to end. 25 00:02:01,980 --> 00:02:02,930 Keypoint amount. 26 00:02:02,930 --> 00:02:10,910 Tor is that no individual node or relay ever knows the complete path the a data pack has taken. 27 00:02:10,920 --> 00:02:15,060 The client negotiates separate sets of encryption. 28 00:02:15,060 --> 00:02:21,090 You can see illustrated here all separate sets of encryption keys for each hop along the circuit to 29 00:02:21,090 --> 00:02:27,150 ensure that each hop can't trace these connections as they pass through to use the same circuit for 30 00:02:27,150 --> 00:02:33,930 connections that happen within the same 10 minutes or so and the later requests are given a new circuit 31 00:02:34,170 --> 00:02:38,130 to keep people from linking your early actions to new ones. 32 00:02:38,130 --> 00:02:46,500 So then you might go from here to here here here and then out let's run through it using the diagrams 33 00:02:46,500 --> 00:02:48,720 provided by Tor themselves. 34 00:02:48,960 --> 00:02:52,030 So first step here you are. 35 00:02:52,170 --> 00:02:57,660 Alice you need to know what are the relays what are the relays that you can connect to that's the first 36 00:02:57,660 --> 00:02:58,260 thing you need. 37 00:02:58,260 --> 00:03:02,660 So in order to do that you need to connect to something called a directory server. 38 00:03:02,880 --> 00:03:07,430 And this is an example a directory server here you can think of it a little bit like DNS. 39 00:03:07,440 --> 00:03:16,190 So you do an encrypted request to this directory server to obtain a list of Tor nodes next Hollis's 40 00:03:16,230 --> 00:03:20,400 Tor client picks a random path to the destination server. 41 00:03:20,790 --> 00:03:31,320 So here we can see the green encrypted lines and coming out of the exit node to Bob or Facebook or whatever 42 00:03:31,320 --> 00:03:31,580 . 43 00:03:31,710 --> 00:03:35,880 And this bit here crucially is not encrypted. 44 00:03:35,880 --> 00:03:44,460 That will be plain text unless you are using an additional layer of encryption such as Hastey CPS. 45 00:03:44,460 --> 00:03:46,980 Now remember this is accessing the surface web. 46 00:03:46,980 --> 00:03:50,650 This is not accessing the dot net or hidden services. 47 00:03:50,820 --> 00:03:52,980 This is just accessing the surface web. 48 00:03:53,040 --> 00:03:53,990 And next. 49 00:03:54,420 --> 00:04:01,680 And if at a later time the user visits another site Alliss to a client selects a second random path 50 00:04:01,680 --> 00:04:10,520 again so we can see a different path and as we've already said this can be every 10 minutes or so. 51 00:04:10,710 --> 00:04:14,870 Talk can't solve all on an empty problems. 52 00:04:14,880 --> 00:04:22,560 It focuses only on protecting the transport of data you need to use protocols specific support software 53 00:04:22,560 --> 00:04:22,850 . 54 00:04:22,890 --> 00:04:27,450 If you don't want the sites you visit to see your identifying information. 55 00:04:27,600 --> 00:04:33,810 For example you can use the tool browser which will go through while browsing the web to withhold some 56 00:04:33,810 --> 00:04:38,160 information about your computer's configuration and will go into all that. 57 00:04:38,160 --> 00:04:42,360 So think of Tor as simply one element. 58 00:04:42,360 --> 00:04:45,920 One tool that enables you to disguise your location. 59 00:04:45,990 --> 00:04:52,500 It is just a tool and it is just one to two it does not provide protection against end and timing attacks 60 00:04:52,500 --> 00:04:52,770 . 61 00:04:52,830 --> 00:04:59,160 If your attacker can watch the traffic coming in and out of your computer and also traffic arriving 62 00:04:59,160 --> 00:05:04,560 at the chosen destination he can use artistical analysis to discover that they are part of the same 63 00:05:04,560 --> 00:05:05,300 circuit. 64 00:05:05,310 --> 00:05:10,030 So Tor is not a panacea for privacy and shouldn't be relied upon as such. 65 00:05:10,050 --> 00:05:15,960 With the right methods and tactics which will go through it can be a very useful tool for aiding in 66 00:05:15,960 --> 00:05:22,650 staying anonymous and the diagram here illustrates the layers of encryption and this is where the term 67 00:05:22,740 --> 00:05:30,960 onion routing comes from is lairs of encryption and these Lares peeled back as you go through the Tor 68 00:05:30,960 --> 00:05:31,850 network. 69 00:05:32,250 --> 00:05:39,330 So the first relay will only see this and we will have these encrypted lairds within it. 70 00:05:39,420 --> 00:05:46,590 The second relay will see this and the third relay will see this until finally the actual message is 71 00:05:46,590 --> 00:05:53,430 received by the destination host which is not encrypted which means that no individual node ever knows 72 00:05:53,430 --> 00:05:56,400 the complete path that a day a packet is taken. 73 00:05:56,400 --> 00:06:02,340 The client is negotiating a separate set of encryption keys for each hop along the circuit to ensure 74 00:06:02,340 --> 00:06:06,780 that each hop can't trace these connections as they passed through. 75 00:06:06,780 --> 00:06:08,460 Let's go through this again. 76 00:06:08,460 --> 00:06:14,490 So your message is encrypted several times and encrypted several times before even leaves your device 77 00:06:14,940 --> 00:06:18,620 node A can only decrypt lair. 78 00:06:18,780 --> 00:06:25,800 And when it's done it will be able to see the address of the next node which is here node be after the 79 00:06:25,800 --> 00:06:28,230 packet reaches the next node node B. 80 00:06:28,270 --> 00:06:37,590 He can only decrypt Labby which is here and so on through the last each Lehre you use a session key 81 00:06:37,590 --> 00:06:41,230 negotiated with the respective nodes public key. 82 00:06:41,370 --> 00:06:46,920 So only the exact know can decrypt the where with it session key when the message reaches the exit node 83 00:06:46,920 --> 00:06:46,970 . 84 00:06:46,980 --> 00:06:54,060 All the letters have been decrypted and the message is now in plain text unless an additional encryption 85 00:06:54,060 --> 00:07:00,570 is used like SSL Diffie Hellman handshake is used to establish those session keys. 86 00:07:00,570 --> 00:07:06,150 David Helmund allows session key negotiation where even a man in the middle observing the traffic would 87 00:07:06,150 --> 00:07:12,180 not be able to determine what the mutually agreed sesshin key was to also utilizers something called 88 00:07:12,180 --> 00:07:18,570 Perfect Forward Secrecy meaning the session keys are ephemeral as they are only used briefly and then 89 00:07:18,570 --> 00:07:19,150 replay. 90 00:07:19,200 --> 00:07:25,290 This then means in the future if one of the nodes is compromised previous data that passed through that 91 00:07:25,290 --> 00:07:31,920 node cannot be discovered and private keys cannot be used to decrypt previous data to basically hide 92 00:07:31,920 --> 00:07:35,610 your IP address on the net where does a reasonable job of it 10290