1 00:00:00,060 --> 00:00:07,620 Going to talk about this also model and all it stands for Open Systems Interconnection, and this was 2 00:00:07,620 --> 00:00:08,100 proposed. 3 00:00:08,100 --> 00:00:13,700 Why are you so I just sort of stands for international standards and organization. 4 00:00:14,610 --> 00:00:21,990 So the main aim is to establish communication between the different systems in the olden days, if you 5 00:00:21,990 --> 00:00:31,860 buy a CPU or any computer peripherals from one company, supposedly, and you need to IBM in order to 6 00:00:31,860 --> 00:00:38,550 say there is no there are be OK, if you say you want to buy a computer from IBM, then you need to 7 00:00:38,550 --> 00:00:46,860 buy the monitor and speakers and everything from the IBM because there is no compatibility between different 8 00:00:46,860 --> 00:00:47,430 devices. 9 00:00:47,940 --> 00:00:53,960 And that's why even in the network, there is no compatibility between not computers. 10 00:00:54,480 --> 00:01:00,480 That's why these are so this whole proposal, this model and this is only theoretical model, but this 11 00:01:00,480 --> 00:01:02,160 is the heart of the cookie. 12 00:01:03,000 --> 00:01:11,260 This model is divided into seven years and each there is like a stack of seven layers and each that 13 00:01:11,310 --> 00:01:12,850 performs its own task. 14 00:01:13,770 --> 00:01:22,020 So these players perform some task and each had its own header to the data, thus enabling encapsulation. 15 00:01:22,170 --> 00:01:30,090 So what this means is that their process, its data could go next year and that next year does not know 16 00:01:30,090 --> 00:01:30,980 about this data. 17 00:01:30,990 --> 00:01:38,580 It simply adds its own header and then send to the next player and so on test. 18 00:01:38,790 --> 00:01:43,020 It doesn't know what data is in there from the previous year. 19 00:01:43,350 --> 00:01:45,230 So let's see are the seven layers. 20 00:01:46,860 --> 00:01:50,730 So as you can see from top to bottom, these are seven layers. 21 00:01:51,060 --> 00:01:57,380 But we will consider from bottom to top that this first one is fiscal data that are there and network 22 00:01:57,390 --> 00:02:01,480 layer transport, recession representation and opposition position there. 23 00:02:02,340 --> 00:02:07,850 So you need to consider from bottom to top this layer, one, two, three, four, five, six, seven. 24 00:02:08,400 --> 00:02:11,540 So since you are running, this is a model. 25 00:02:11,550 --> 00:02:17,520 I have mentioned the names, but in general, when you are going for interviews, you do not mention 26 00:02:17,520 --> 00:02:24,090 that because the only thing that you recently learned this, that names, that's what you are mentioning, 27 00:02:24,090 --> 00:02:27,420 that they always mentioned that layer number. 28 00:02:27,570 --> 00:02:29,320 So one, two, three. 29 00:02:29,340 --> 00:02:33,560 So if this is if you want to mention transfer 104. 30 00:02:34,260 --> 00:02:40,680 So in that case, the circumstances that you have some better understanding of these layers, but mention 31 00:02:40,680 --> 00:02:44,800 that layer names, um, near the haters. 32 00:02:44,820 --> 00:02:47,700 Are any interviews OK, coming to the future? 33 00:02:47,760 --> 00:02:49,080 This is one fiscal year. 34 00:02:49,380 --> 00:02:56,280 This fiscal year consist of the wires, cables and the network devices. 35 00:02:57,090 --> 00:03:00,840 And Hub's comes into this fiscal year and this is great. 36 00:03:00,850 --> 00:03:02,940 These are with the transmission of bits. 37 00:03:03,510 --> 00:03:07,740 So in ways that I will be sent as if it's zeros and ones. 38 00:03:08,160 --> 00:03:10,810 And coming to this referred to is the data. 39 00:03:12,030 --> 00:03:19,920 So at this where the switches operate at this rate, thus we just transfer the data from one computer 40 00:03:19,920 --> 00:03:21,840 to another computer based on a Mac address. 41 00:03:22,350 --> 00:03:32,190 And these switches calls the macro stable of these computers and then transfer the data from one country 42 00:03:32,190 --> 00:03:36,600 to another computer based on the megadoses, I mean the megadoses. 43 00:03:36,930 --> 00:03:44,820 So the main important thing you need to know about this layer to these switches perform at this rate 44 00:03:45,630 --> 00:03:48,210 and the coming together to this network layer. 45 00:03:48,360 --> 00:03:51,150 And at this layer, rotas perform. 46 00:03:51,420 --> 00:03:57,200 But in general, Rodust perform all the task up to these three layers. 47 00:03:57,360 --> 00:04:05,190 But generally it is mentioned that routers operate at this rate and routers are responsible for assigning 48 00:04:05,190 --> 00:04:11,940 the IP address on computer and doing some other network address, translation and portraitist translations 49 00:04:12,450 --> 00:04:21,600 to maintain the IP addresses to not to exceed the IP address remit. 50 00:04:21,930 --> 00:04:25,130 So we talking with this network and Bridgid in a separate video. 51 00:04:25,950 --> 00:04:35,160 So all of this may work at this network and then transfer these ladieswear defines how your data should 52 00:04:35,160 --> 00:04:37,530 be sent to the source to destination. 53 00:04:37,920 --> 00:04:41,580 And we need to implement two protocols as a TCP are. 54 00:04:43,440 --> 00:04:50,130 These are the main two transfer protocols and we see what this DCP and UDP supported. 55 00:04:51,150 --> 00:04:55,970 And this stands for also I say in the put numbers. 56 00:04:56,280 --> 00:04:59,580 So if you want to send it to a computer to particular. 57 00:04:59,860 --> 00:05:07,500 Service, there will be a number and on the bottom where the service will be running on, so this transporter 58 00:05:07,510 --> 00:05:15,130 assigns that which protocol to send and also the phone number to send this session there will initiate 59 00:05:15,130 --> 00:05:18,050 the session from these variables spot. 60 00:05:19,240 --> 00:05:22,960 So it makes sure that our we are connecting to the right destination or not. 61 00:05:24,100 --> 00:05:26,560 And this is presentation. 62 00:05:26,950 --> 00:05:31,800 So in what format we should send the data such that the nation could understand. 63 00:05:32,860 --> 00:05:39,720 So in our Prešov or any other format and the application of these the layers of it. 64 00:05:39,910 --> 00:05:46,330 And these are the Navar applications running on the users like browser Ottone user application. 65 00:05:48,100 --> 00:05:49,990 So what this does is. 66 00:05:52,280 --> 00:05:59,930 You just these are the applications and these applications also run some other protocols like the GDP 67 00:06:00,320 --> 00:06:05,200 and DPS and so on, we'll be seeing the protocols later. 68 00:06:05,480 --> 00:06:08,480 But one hour, one way too easy to do. 69 00:06:08,570 --> 00:06:09,890 What are these names? 70 00:06:09,900 --> 00:06:10,150 His. 71 00:06:11,510 --> 00:06:16,970 Well, just remember these words, please do not throw sausages with the other hand, if you hear the 72 00:06:16,970 --> 00:06:24,120 fighting words, you can see be for physical year before that and for for transport. 73 00:06:24,830 --> 00:06:28,340 As for session and for presentation and for application. 74 00:06:29,680 --> 00:06:34,780 So there are so many examples like this, but this is the most famous one, please do not let me go 75 00:06:34,790 --> 00:06:35,010 there. 76 00:06:35,890 --> 00:06:40,240 And this is like a stack of seven letters, although it's a model. 77 00:06:41,020 --> 00:06:45,970 And I want to show you another slide that is considered this as the source. 78 00:06:45,970 --> 00:06:49,090 And this are the destination right from the source. 79 00:06:50,020 --> 00:06:55,630 I had the process of producing and I want to or any user I want to send the data from this computer 80 00:06:55,630 --> 00:06:56,480 to this computer. 81 00:06:56,800 --> 00:07:01,210 So what this application does is it will send this data to presentation. 82 00:07:01,810 --> 00:07:08,380 So this presentation layer adds its own header and it will send the whole data to this session layer, 83 00:07:08,650 --> 00:07:10,390 which contained this presentation header. 84 00:07:10,690 --> 00:07:14,800 And this session in turn adds its own header and sends it to transport. 85 00:07:15,340 --> 00:07:23,500 So by this measure, it at the end you will get all the headers, including all these letters, respective 86 00:07:23,500 --> 00:07:23,910 headers. 87 00:07:24,160 --> 00:07:31,450 And after this is clear, the data is converted into bits and transferred to the destination at the 88 00:07:31,450 --> 00:07:31,960 destination. 89 00:07:31,960 --> 00:07:37,180 Or does this the data content of the headers of these letters? 90 00:07:37,180 --> 00:07:45,520 And what this does is it will identify each letter header and remove it and it will pass the remaining 91 00:07:45,520 --> 00:07:46,730 data to the operator. 92 00:07:46,870 --> 00:07:53,770 These are network layer and then this in turn started for the network header and it was the most, uh, 93 00:07:53,770 --> 00:08:00,670 remotes and send the data to the operators in the same way the data is encapsulated by headers and then 94 00:08:00,680 --> 00:08:04,810 becomes routed at the destination site and the data is sent to the application. 95 00:08:05,320 --> 00:08:13,420 So in this case, this list does not understand that the actual data, it just captures the whole data 96 00:08:13,420 --> 00:08:15,340 and sent to the blue layer. 97 00:08:16,720 --> 00:08:19,870 So make sure you're going to talk about is TCP IP model. 98 00:08:20,260 --> 00:08:28,510 That was a model we have talked of is a theoretically more theoretical model and it does not then not 99 00:08:28,510 --> 00:08:29,090 implement that. 100 00:08:29,350 --> 00:08:31,030 It is very tough to implement that one. 101 00:08:31,240 --> 00:08:33,760 That's what the House did, some modifications. 102 00:08:33,760 --> 00:08:38,720 And in 1960s also this particular don't know exactly. 103 00:08:38,740 --> 00:08:40,980 So this model was introduced. 104 00:08:41,920 --> 00:08:49,960 What they did is they have me do some of this and define this for this question is one this week content 105 00:08:49,960 --> 00:08:51,660 that are in clear and physical data. 106 00:08:52,240 --> 00:08:59,840 So they how much of it got a little grayer and features hubs work at this layer and the network of terrorist 107 00:08:59,870 --> 00:09:03,450 networks create similar layer and transfer to also transfer. 108 00:09:03,730 --> 00:09:07,590 And one important note is you can use this application layer. 109 00:09:07,780 --> 00:09:14,830 There are there is no session and presentation because they have believed that the application itself 110 00:09:14,830 --> 00:09:17,740 can present the data. 111 00:09:17,750 --> 00:09:25,380 I mean, for the data and the specific format and then application itself can initiate a connection. 112 00:09:25,570 --> 00:09:25,930 Right. 113 00:09:26,260 --> 00:09:34,690 So suppose if you say a browser, you in your browser, you will send that request, the hatchetman 114 00:09:34,690 --> 00:09:39,820 file from the server and even you are initiating the connection using the browser. 115 00:09:39,820 --> 00:09:40,170 Right. 116 00:09:40,420 --> 00:09:41,560 That is far from the session. 117 00:09:42,010 --> 00:09:49,810 And the browser is able to decode that fumer and it is showing you need format of the application itself 118 00:09:49,810 --> 00:09:53,900 is doing some presenting work for formatting work for you. 119 00:09:54,340 --> 00:10:00,310 So and also application that includes the application itself and also protocols associated with that 120 00:10:00,310 --> 00:10:00,970 application. 121 00:10:02,110 --> 00:10:08,920 So since applications, modern applications are doing these tasks, they have merged those two years 122 00:10:08,920 --> 00:10:09,610 into application. 123 00:10:11,080 --> 00:10:16,180 So this is a practical model we are using right now. 124 00:10:16,540 --> 00:10:19,000 And the model is only theoretical model.