1 00:00:00,620 --> 00:00:02,510 The Internet Protocol suite. 2 00:00:02,700 --> 00:00:07,400 TCP IP is a de facto protocol that modern networks use. 3 00:00:07,430 --> 00:00:12,650 Although you can think of the TCP IP as a single protocol, it's actually a combination of two protocols 4 00:00:12,680 --> 00:00:19,730 the transmission control protocol, TCP and the Internet protocol IP. 5 00:00:19,940 --> 00:00:24,860 And these two protocols form part of the Internet protocol suite. 6 00:00:24,890 --> 00:00:25,760 IP. 7 00:00:26,030 --> 00:00:27,590 So this is the Internet protocol suite. 8 00:00:27,590 --> 00:00:31,720 And these diagrams and I will explain all of these diagrams right now here. 9 00:00:31,730 --> 00:00:32,510 So. 10 00:00:33,760 --> 00:00:36,240 Um, and this Internet protocol suite. 11 00:00:36,250 --> 00:00:44,620 This is the conceptual model of how network protocols send network traffic over the Internet that breaks 12 00:00:44,620 --> 00:00:51,580 down network communication into four layer as shown in here. 13 00:00:51,580 --> 00:00:59,200 So application layer, transport layer, internet layer link layer and Ethernet IP is link layer IPv4. 14 00:00:59,200 --> 00:01:04,120 IPv6 is Internet layer, TCP and UDP is transport layer. 15 00:01:04,120 --> 00:01:06,610 Actually let me add comma here. 16 00:01:07,090 --> 00:01:15,820 TCP and UDP is transport layer HTTP SMTP, DNS is and etcetera is application layer and is actually 17 00:01:15,820 --> 00:01:24,790 these protocols are more but just this is just most used protocols in internet protocol suite and these 18 00:01:24,790 --> 00:01:26,680 are the external connections here. 19 00:01:26,680 --> 00:01:34,550 So the link layer directly connects to a physical network and also physical network connects directly 20 00:01:34,550 --> 00:01:36,740 to link layer here. 21 00:01:36,740 --> 00:01:39,800 So actually, let me get this here. 22 00:01:40,340 --> 00:01:45,320 Here and here I will apply the same for user application. 23 00:01:45,320 --> 00:01:45,980 Right? 24 00:01:47,130 --> 00:01:54,780 Here, whether it is a browser or just an online game, this is what works like that. 25 00:01:54,780 --> 00:01:57,840 So now I will explain Internet protocol suite. 26 00:01:57,870 --> 00:02:02,640 So let's get started with the link layer, the this link layer here. 27 00:02:02,640 --> 00:02:11,520 So this layer is the lowest level and describes the physical mechanisms used to transfer information 28 00:02:11,520 --> 00:02:20,070 between nodes on a local network and the well known examples include the Ethernet, both wired and wireless 29 00:02:20,070 --> 00:02:23,760 and the point to point protocol p, p. 30 00:02:23,770 --> 00:02:24,330 P. 31 00:02:24,510 --> 00:02:28,680 We also have the internet layer here. 32 00:02:29,040 --> 00:02:34,860 So this layer provides the mechanisms for addressing network nodes. 33 00:02:34,860 --> 00:02:42,090 And unlike in the in layer one, this the nodes doesn't have to be located on the local network. 34 00:02:42,120 --> 00:02:45,810 This level contains the IP on modern networks. 35 00:02:45,810 --> 00:02:50,230 The actual protocol used could be either IP version four or IP version six. 36 00:02:50,830 --> 00:02:54,400 And here we also have the transport layer. 37 00:02:54,430 --> 00:03:00,460 So this layer is responsible for connections between clients and servers and sometimes ensuring the 38 00:03:00,460 --> 00:03:03,220 correct order of packets and providing service. 39 00:03:03,220 --> 00:03:09,280 Multiplexing and service multiplexing allows a single node to support multiple different services by 40 00:03:09,280 --> 00:03:11,980 assigning a different number for each service. 41 00:03:11,980 --> 00:03:14,680 And this number is called the port. 42 00:03:14,710 --> 00:03:25,190 So the TCP and user datagram protocol operate on this layer and we also have the application layer. 43 00:03:25,210 --> 00:03:34,090 So this layer contains network protocols such as the hypertext transfer protocol HTTP, which transfers 44 00:03:34,210 --> 00:03:43,630 web page contents and the simple mail transport protocol SMTP, which transfers the email and the domain 45 00:03:43,630 --> 00:03:51,340 name system protocol DNS here, which converts a name to a node on the network. 46 00:03:51,350 --> 00:03:56,780 Throughout this course, we will focus primarily on this layer. 47 00:03:56,780 --> 00:04:04,780 Actually, in this section we will focus primarily on this layer, but in our all of our course you 48 00:04:04,790 --> 00:04:07,250 will learn all of these layers and protocols. 49 00:04:07,250 --> 00:04:09,200 So see you in next lecture.