1 00:00:00,090 --> 00:00:01,290 What's up everybody. 2 00:00:01,320 --> 00:00:07,740 So I'm going to preface this video really quick with that it is raining pretty hard here so if the soothing 3 00:00:07,740 --> 00:00:13,020 sounds of the rain put you to sleep during this video and you can hear it I'm very very sorry but the 4 00:00:13,020 --> 00:00:14,280 show must go on. 5 00:00:14,700 --> 00:00:19,890 So we're gonna be doing today is there going to be talking about IP addresses. 6 00:00:19,920 --> 00:00:26,160 Now if you've ever used a computer before and you're any anyone familiar with I.T. you probably know 7 00:00:26,170 --> 00:00:27,920 an IP addresses. 8 00:00:28,170 --> 00:00:35,280 But I want to take this a little bit deeper in in theory on why we use IP addresses what types of IP 9 00:00:35,280 --> 00:00:40,710 addresses are out there and talk more about protocols and how IP addresses are actually designed and 10 00:00:40,710 --> 00:00:42,010 made up. 11 00:00:42,030 --> 00:00:48,800 So I'm here in a Cowley terminal and I'm just going to type in a simple command in that command is i 12 00:00:48,800 --> 00:00:50,060 f config. 13 00:00:50,070 --> 00:00:54,380 Now if you've used Linux before this might be familiar to you if you use Windows. 14 00:00:54,390 --> 00:00:56,700 It's similar to IP config. 15 00:00:56,730 --> 00:01:03,690 All I'm trying to do is bring up my IP address so we can see here is that we have an IP address which 16 00:01:03,690 --> 00:01:05,300 is our iiNet. 17 00:01:05,310 --> 00:01:07,490 This is my IP address here. 18 00:01:07,500 --> 00:01:09,180 I also have another IP address. 19 00:01:09,210 --> 00:01:13,230 This iiNet Six this is what's called an IP B address. 20 00:01:13,260 --> 00:01:21,720 So we've got this iiNet which is considered an IP before in this iiNet 6 which is considered IP v 6. 21 00:01:21,720 --> 00:01:27,720 Now you can notice right away that there's two different types of notations for these this iiNet here 22 00:01:27,720 --> 00:01:34,790 is in a decimal notation and the IP 6 is in a hexadecimal notation. 23 00:01:34,800 --> 00:01:38,140 We'll get to the importance of that in just a second. 24 00:01:38,190 --> 00:01:43,260 So when it comes to IP addresses this looks probably pretty familiar to us. 25 00:01:43,290 --> 00:01:45,030 This is an IP address. 26 00:01:45,030 --> 00:01:46,430 This is how we communicate. 27 00:01:46,440 --> 00:01:51,840 We communicate over Layer 3 and you're going to hear we talking about layers repeatedly throughout the 28 00:01:51,840 --> 00:01:54,890 course or at least throughout this part of the course. 29 00:01:55,020 --> 00:01:59,260 So that we can get familiar with how we're actually doing this. 30 00:01:59,280 --> 00:02:04,710 So I want you to be familiar with troubleshooting these layers and these layers all refer to something 31 00:02:04,710 --> 00:02:06,660 called the os sy model. 32 00:02:06,660 --> 00:02:12,120 So when we talk about layers we think about the LSI model and I'll introduce the LSI model here in a 33 00:02:12,120 --> 00:02:15,120 few videos and it should all click. 34 00:02:15,120 --> 00:02:19,910 Once I introduce the ISI model so if I brought in the LSI model up front it might be boring might not 35 00:02:19,920 --> 00:02:20,820 make sense. 36 00:02:20,820 --> 00:02:25,190 Some introduce the OS model near the end and say hey yeah that all makes sense. 37 00:02:25,200 --> 00:02:32,430 So what we've got here is we've got this IP for address and this is the most commonly use format that 38 00:02:32,430 --> 00:02:33,240 we use today right. 39 00:02:33,240 --> 00:02:35,680 We use IP for mostly everything. 40 00:02:35,820 --> 00:02:38,430 And again this isn't that decimal notation. 41 00:02:38,430 --> 00:02:44,400 So when we see this decimal notation it's just a realistically a bunch of ones and zeros that are put 42 00:02:44,400 --> 00:02:47,820 together so that we have this human readable format. 43 00:02:48,270 --> 00:02:54,330 Realistically all we're seeing here with one ninety to this first this first section here this first 44 00:02:54,390 --> 00:02:59,160 octet is actually just a bunch of ones and zeros it's eight bits. 45 00:02:59,160 --> 00:03:02,920 So we've got a range of eight ones and zeros here. 46 00:03:03,030 --> 00:03:06,550 We've got another eight here eight here and eight here. 47 00:03:06,570 --> 00:03:13,890 So when it's all said and done this iiNet or this IP v four is made up of 32 bits eight plus eight plus 48 00:03:13,920 --> 00:03:17,430 eight plus eight here and which equals four bytes. 49 00:03:17,760 --> 00:03:22,920 So another way to think about that is to think about it as say something like this. 50 00:03:22,950 --> 00:03:25,720 One two three four five six seven eight. 51 00:03:25,980 --> 00:03:26,770 Period. 52 00:03:27,030 --> 00:03:27,330 OK. 53 00:03:27,330 --> 00:03:29,130 That is one section there. 54 00:03:29,610 --> 00:03:32,520 So we've got eight ones that can make up this. 55 00:03:32,670 --> 00:03:35,090 And then we'd have another eight et cetera. 56 00:03:35,160 --> 00:03:39,180 Not going to beat a dead horse here but I do want to give you guys another example. 57 00:03:39,180 --> 00:03:43,560 So if we go into our applications and we go to a text editor really quick. 58 00:03:43,560 --> 00:03:48,220 So the way this looks is something like this. 59 00:03:48,360 --> 00:03:53,380 We start with a number like 128 to spaces out as best as possible. 60 00:03:53,520 --> 00:03:59,000 And all I like to do is think of 128 as my base and this will make a lot more sense when we get into 61 00:03:59,000 --> 00:04:04,310 the subducting so please if you're confused by this Don't worry this is all theory right now. 62 00:04:04,440 --> 00:04:09,480 When we get into sub meaning we get hands on it I'll make a lot more sense I promise you. 63 00:04:09,510 --> 00:04:12,530 So let's say we have ones and zeros here. 64 00:04:12,660 --> 00:04:18,960 If we have a one for each of these sections and I'm going to spaces out again as best as possible it's 65 00:04:18,960 --> 00:04:25,080 not pretty but if we have a one for all these this equals two fifty five why does this equal to fifty 66 00:04:25,080 --> 00:04:25,710 five. 67 00:04:26,040 --> 00:04:32,010 Well you take this and all these numbers add up one plus two plus four plus eight all this adds up to 68 00:04:32,030 --> 00:04:33,360 255. 69 00:04:33,390 --> 00:04:42,420 So let's say if we didn't have all the ones zeros we had just some ones enabled like these last three 70 00:04:42,420 --> 00:04:43,230 here. 71 00:04:43,260 --> 00:04:43,640 OK. 72 00:04:43,650 --> 00:04:49,810 Well this one equals seven because we have four plus two plus one equals seven. 73 00:04:49,860 --> 00:04:55,260 So our first number or whatever number this apply to in the Octet will be seven. 74 00:04:55,260 --> 00:05:03,010 So if we had seven seven seven seven it would just this numbers repeating over and over these numbers 75 00:05:03,010 --> 00:05:03,790 repeating over and over. 76 00:05:03,790 --> 00:05:04,030 Right. 77 00:05:04,060 --> 00:05:11,690 So be 0 0 0 0 1 1 1 dot 0 0 0 0 1 1 1 and so forth. 78 00:05:12,190 --> 00:05:17,020 So this is kind of what it looks like behind the scenes because again a computer is just ones and zeros 79 00:05:17,020 --> 00:05:22,540 we're all binary so we're going to do is we're in closes out or talk a little bit of other theory when 80 00:05:22,540 --> 00:05:31,210 it comes to this and why I net or HPV 6 and why ITV 4 so let's close this and let's talk about IP for 81 00:05:32,110 --> 00:05:37,990 somebody bring up a calculator and with IP before we have these 32 bit. 82 00:05:37,990 --> 00:05:46,890 So what we can do is we could take two to 30 second power and this is the possible amount of IP addresses 83 00:05:46,890 --> 00:05:47,610 that we could have. 84 00:05:47,640 --> 00:05:52,050 So we have somewhere in the 4 billion range of IP addresses. 85 00:05:52,050 --> 00:05:59,040 Well spoiler alert we don't have only four billion people on earth right where we're up to seven something 86 00:05:59,040 --> 00:06:00,400 billion at this point. 87 00:06:00,540 --> 00:06:03,800 And all these IP address spaces are gone. 88 00:06:03,810 --> 00:06:07,580 So ITV 4 has been around since 1981. 89 00:06:07,620 --> 00:06:10,570 Nobody thought we were ever going to use all these addresses. 90 00:06:10,740 --> 00:06:12,560 Computers weren't really a thing. 91 00:06:12,570 --> 00:06:14,980 Who knew that we were going to want all these addresses. 92 00:06:15,120 --> 00:06:21,470 And you know at these companies started buying them up and they started buying them up in large chunks 93 00:06:21,780 --> 00:06:25,450 and then they sold those to ISP fees and then ISP sell those to you. 94 00:06:25,470 --> 00:06:33,090 And so these IP addresses have been gone for a very very long time and chances are when you when you 95 00:06:33,090 --> 00:06:38,100 have an IP address and you get this IP before you're only going to get one if you're a corporation you 96 00:06:38,100 --> 00:06:39,340 might buy more. 97 00:06:39,480 --> 00:06:41,660 But we've run out of IP address space. 98 00:06:41,730 --> 00:06:43,140 There's just not enough to go around. 99 00:06:43,620 --> 00:06:48,060 So the theory is OK let's come up with something different. 100 00:06:48,150 --> 00:06:50,940 Let's come up with IP 6. 101 00:06:50,940 --> 00:06:58,200 Now this hexadecimal is actually in one hundred and twenty eight bits which makes things just a little 102 00:06:58,200 --> 00:07:00,450 bit longer and adds quite a bit. 103 00:07:00,450 --> 00:07:07,620 So let's take this two to one hundred twenty eight power and we get a number that I can not tell you 104 00:07:07,620 --> 00:07:13,620 how to say nine I'm going to try but I can guarantee you that in our lifetime we will never use this 105 00:07:13,620 --> 00:07:20,450 address based so we've come up with the solution of IPD sex but nobody really uses it. 106 00:07:20,530 --> 00:07:23,480 IPD 6 is just a thing that's there. 107 00:07:23,490 --> 00:07:30,570 But when we we get IP these six addresses a sign but still to this day everybody's using IP before. 108 00:07:30,600 --> 00:07:32,750 Well how how is that possible. 109 00:07:32,760 --> 00:07:36,030 If we're using IP before but we're out of address space. 110 00:07:36,060 --> 00:07:38,550 Well think about this. 111 00:07:38,550 --> 00:07:43,590 We're using something called net which is network address translation. 112 00:07:43,590 --> 00:07:45,720 Now let's think about your network. 113 00:07:45,840 --> 00:07:52,110 So you might have a cell phone or computer or multiple devices my network has at least 20 devices on 114 00:07:52,110 --> 00:08:00,630 it I've got I've got cameras I've got multiple cell phones smart TV is everything that connects to my 115 00:08:00,630 --> 00:08:05,900 Internet gets an IP address and that's 20 IP addresses right there. 116 00:08:05,900 --> 00:08:06,180 Right. 117 00:08:06,210 --> 00:08:08,970 So let's say I have 20 devices that's 20 IP addresses. 118 00:08:09,030 --> 00:08:13,350 Am I taking up 20 IP addresses out of that 4 billion. 119 00:08:13,350 --> 00:08:13,950 No. 120 00:08:14,130 --> 00:08:19,030 We're actually using something called network address translation or it's called net for short. 121 00:08:19,230 --> 00:08:25,070 And we'll talk about this again when we we set up our actual lab. 122 00:08:25,200 --> 00:08:30,870 But with that what we're doing is we're assigned these private IP address spaces. 123 00:08:30,900 --> 00:08:36,570 So we've got this 1 9 2 1 6 8 dot fifty seven dot one thirty nine. 124 00:08:36,570 --> 00:08:42,060 Now if you've ever seen a IP address before and you've been on a network good chances are it probably 125 00:08:42,060 --> 00:08:43,510 started with one ninety two. 126 00:08:43,680 --> 00:08:47,500 Or maybe it started with a 10 dot or something along those lines. 127 00:08:47,580 --> 00:08:49,840 And that's because those are private IP addresses. 128 00:08:49,950 --> 00:08:59,310 So anything that starts with 1 9 2 1 6 8 is not an IP address that is going to be out in the the interweb. 129 00:08:59,310 --> 00:09:02,490 It is going to be an IP address that is only known to you. 130 00:09:02,490 --> 00:09:04,780 These are called private IP addresses. 131 00:09:04,890 --> 00:09:11,040 So because we use these private IP addresses we can pass them out through what is called a public IP 132 00:09:11,040 --> 00:09:11,980 address. 133 00:09:12,000 --> 00:09:18,490 Now to make better use of this let's go out to Firefox I've already got a tab open so I went to Google 134 00:09:18,790 --> 00:09:22,900 and I just said private IP addresses and I clicked the second image here because I think it's a great 135 00:09:22,900 --> 00:09:23,770 image. 136 00:09:23,770 --> 00:09:28,600 So if we look at this there are classes of IP addresses private IP addresses. 137 00:09:28,600 --> 00:09:31,170 Now there is a Class D and E. 138 00:09:31,180 --> 00:09:36,580 We're not going to worry about those the big three are Class A B and C if you know these you are are 139 00:09:36,580 --> 00:09:38,120 good to go. 140 00:09:38,140 --> 00:09:44,560 So if we look at Class C this is what the most common household and small business use. 141 00:09:44,620 --> 00:09:51,760 So we see it starts with the 1 9 2 1 that 0 0 so the 1 9 2 168 are constant. 142 00:09:51,760 --> 00:09:57,420 If you see a 1 9 2 1 6 8 address you can guarantee yourself that that is a private IP address base. 143 00:09:57,790 --> 00:10:04,750 And then we have the range of changing this number between 0 and 255 and this number between 0 and 255 144 00:10:05,290 --> 00:10:06,970 y 0 to 255. 145 00:10:06,970 --> 00:10:09,620 Well that'll all make sense when we get into submitting. 146 00:10:10,090 --> 00:10:16,930 But what that allows us to do is have a large number of networks here and a small amount of hosts. 147 00:10:16,960 --> 00:10:26,020 But for a a regular user like you or I or a small business two hundred fifty four hosts is pretty good. 148 00:10:26,020 --> 00:10:28,380 I mean I'm only using 920 20 in my household. 149 00:10:28,390 --> 00:10:32,560 So the most common household is probably using this 1 9 to address. 150 00:10:32,560 --> 00:10:35,350 But what about a big big business. 151 00:10:35,350 --> 00:10:35,650 Right. 152 00:10:35,650 --> 00:10:37,350 Something huge. 153 00:10:37,360 --> 00:10:44,440 OK well they might use a 10 address because a 10 address frees you up to anything after this 10 is private. 154 00:10:44,470 --> 00:10:50,500 So 10 dot 1 10 not one dot one dot one whatever you want to put in here up to two fifty five on each 155 00:10:50,560 --> 00:10:57,550 octet makes for a small amount of networks but a large amount of hosts. 156 00:10:57,970 --> 00:10:58,320 OK. 157 00:10:58,330 --> 00:11:02,240 And don't worry about the hosts Versus network thing again submitting. 158 00:11:02,350 --> 00:11:03,360 We'll talk about that. 159 00:11:03,370 --> 00:11:04,770 It all makes sense. 160 00:11:05,140 --> 00:11:10,300 But just imagine the amount of amount of hosts that you can get in here with this wide range. 161 00:11:10,300 --> 00:11:14,890 So because of this you'll see larger corporations using 10 addresses. 162 00:11:14,890 --> 00:11:20,110 You'll also see a lot of corporations even small businesses using 10 addresses the the matter of fact 163 00:11:20,110 --> 00:11:26,700 is as long as you have this private IP address you're good to communicate across your network. 164 00:11:26,770 --> 00:11:33,480 So any IP address outside of these in the loop back here are free game for the public address space. 165 00:11:33,490 --> 00:11:40,390 They're probably already owned and you purchased those or rent those really from your ISP your Internet 166 00:11:40,390 --> 00:11:41,710 service provider. 167 00:11:41,710 --> 00:11:48,900 So going back to this thought we have a classy address my networks Class C 1 9 2 1 6 8 fifty seven one 168 00:11:48,910 --> 00:11:50,380 thirty nine here. 169 00:11:50,380 --> 00:11:57,220 So it falls into that class C I got all these devices on this 1 9 2 1 6 8 network all of these devices 170 00:11:57,220 --> 00:11:59,470 are talking out of one IP address. 171 00:11:59,470 --> 00:12:01,360 That is my public IP address. 172 00:12:01,480 --> 00:12:08,170 That is what I rent from my ISP and all this network traffic goes out one ip. 173 00:12:08,620 --> 00:12:15,820 So this is how we have achieved or solve the issue of running out of address space without having to 174 00:12:15,820 --> 00:12:17,610 use IP B6. 175 00:12:17,620 --> 00:12:20,490 Now there's anything wrong with IP these six. 176 00:12:20,620 --> 00:12:21,490 It's not pretty. 177 00:12:21,490 --> 00:12:24,970 I mean it's way easier to type this stuff in than it would be to take something like this in. 178 00:12:26,500 --> 00:12:28,980 But at the same time this is how we've solved it. 179 00:12:28,990 --> 00:12:36,310 We've eight we're able to still use IP before and mostly all networks and we are able to communicate 180 00:12:36,310 --> 00:12:39,780 out with this quote unquote IP address shortage. 181 00:12:40,060 --> 00:12:42,830 So hopefully that makes sense. 182 00:12:42,910 --> 00:12:45,130 We're going to build upon these concepts again. 183 00:12:45,400 --> 00:12:47,270 IPTV for IP 6. 184 00:12:47,290 --> 00:12:53,050 IP addresses are Layer 3 protocols Layer 3 is a router. 185 00:12:53,050 --> 00:12:56,770 So when we route traffic we route via an IP address. 186 00:12:56,770 --> 00:12:59,910 So we're gonna build upon that as well as we go in. 187 00:12:59,950 --> 00:13:02,550 Hopefully this is all just a refresher to you. 188 00:13:02,560 --> 00:13:04,320 So that is it for this video. 189 00:13:04,330 --> 00:13:06,220 I'll go ahead and catch you over in the next one.