1 00:00:06,620 --> 00:00:10,910 In this video I would like to give you a quick introduction to what is needed to do networking. 2 00:00:11,929 --> 00:00:15,269 In the end, all networking ends in the Internet. 3 00:00:16,230 --> 00:00:17,350 That's where you want to go to. 4 00:00:18,030 --> 00:00:22,745 But if you work in bigger network environments, well, you have your local network and 5 00:00:22,745 --> 00:00:27,460 maybe you even have more than one local network represented by these white lines. 6 00:00:28,640 --> 00:00:33,859 First thing you need to do to make networking possible, you need to connect the networks together. 7 00:00:34,719 --> 00:00:37,420 And that is by using R, which stands for router. 8 00:00:38,340 --> 00:00:42,570 So your network needs to have a router to get to the Internet. And if you 9 00:00:42,570 --> 00:00:46,799 have two local networks, then you need a router to connect the networks together as well. 10 00:00:48,200 --> 00:00:51,704 Then you have your own computers which are the nodes on the 11 00:00:51,704 --> 00:00:55,209 different network networks and they need to be provided with addresses. 12 00:00:56,149 --> 00:00:58,259 IPv4 is the default addressing. 13 00:00:58,840 --> 00:01:01,670 And to start with, every network needs its own network. 14 00:01:02,429 --> 00:01:06,590 And to start with, every network needs its own IP network address. 15 00:01:06,829 --> 00:01:08,829 Like 192.168.0.0 24. 16 00:01:12,230 --> 00:01:16,365 We indicate 24 to tell the network address that the first three 17 00:01:16,365 --> 00:01:20,500 bytes are for networking and the last byte is for node addressing. 18 00:01:21,140 --> 00:01:28,140 And that means that if we have 2, 3, 4 and a 1 right here, that we have these IP addresses. 19 00:01:28,159 --> 00:01:28,500 192.168.0.1192.168.0.2 and so on. 20 00:01:35,459 --> 00:01:38,719 And if you have different networks, every network needs its own IP address. 21 00:01:38,769 --> 00:01:43,174 So let's say this is 192.168.1.0 24, where 22 00:01:43,174 --> 00:01:47,579 the nodes also have their unique IP addresses. 23 00:01:48,140 --> 00:01:50,680 And we need the IP address on the router as well. 24 00:01:52,069 --> 00:01:57,269 Now, big question is what is a node going to do if it wants to go to the Internet? 25 00:01:58,109 --> 00:02:02,239 Let's say this guy wants to reach out to the Internet. Well, imagine the flow. 26 00:02:02,739 --> 00:02:09,009 Then it needs to go through the router, from this router to another router where the packet will end on the Internet. 27 00:02:10,229 --> 00:02:15,240 In order to get this done, we have the setting of the default gateway. 28 00:02:16,000 --> 00:02:21,870 The default gateway is always a router on the network that is required to go externally. 29 00:02:22,500 --> 00:02:25,460 So for this node, this will be the default gateway. 30 00:02:25,960 --> 00:02:26,780 And what does that mean? 31 00:02:27,030 --> 00:02:29,150 Well, if we look at the IP address that will be 192.168.0.1. 32 00:02:33,550 --> 00:02:38,939 Frequently you will see that the default gateway is either the lowest or the highest IP address in the network. 33 00:02:39,840 --> 00:02:44,180 Now that would allow you to reach nodes on the Internet by IP address. 34 00:02:44,759 --> 00:02:51,139 Most people want to make it a little bit easier. And in order to make it easier, there is a system called DNS. 35 00:02:51,849 --> 00:02:54,169 DNS is the domain name system. 36 00:02:55,009 --> 00:03:00,709 So if you want to use domain names like google.com for instance, that's a DNS name and you 37 00:03:00,709 --> 00:03:06,409 need to find the IP address that belongs to the domain name that you want to use. 38 00:03:07,449 --> 00:03:13,349 That is why on every node that you are going to configure with IPv4, you need three different settings. 39 00:03:13,949 --> 00:03:19,235 You need the setting of the local IP address, you need the setting of the default gateway, and 40 00:03:19,235 --> 00:03:24,520 you need the setting of the DNS. And once that is configured, you can communicate on the Internet. 41 00:03:25,120 --> 00:03:28,919 Sometimes it doesn't work well and then you need to investigate what is going on.