1 00:00:00,510 --> 00:00:03,330 You probably using it right now is 2 00:00:14,930 --> 00:00:16,040 don't deny it. 3 00:00:16,040 --> 00:00:18,350 You probably using DHEA P.. 4 00:00:18,410 --> 00:00:25,950 If you're watching this video whether it's on a device like this notice using DHEA P to connect to the 5 00:00:25,950 --> 00:00:30,120 Internet or perhaps on a computer. 6 00:00:30,150 --> 00:00:33,900 Modern networks rely very heavily on DHEA. 7 00:00:33,960 --> 00:00:39,840 For example if you go to Starbucks or a coffee shop or you go to the airport it's very unlikely that 8 00:00:39,840 --> 00:00:44,370 you're going to be walking around saying what's the I.P. address that I should be using. 9 00:00:44,400 --> 00:00:49,860 Which IP address should I configure my device as very unlikely that you're going to be doing that. 10 00:00:49,860 --> 00:00:55,620 And the reason for that is IP addresses are more often than not dynamically allocated especially to 11 00:00:55,620 --> 00:00:57,420 client devices. 12 00:00:57,420 --> 00:01:05,010 So here's an example of some client devices client devices could be pieces could be Internet of Things 13 00:01:05,010 --> 00:01:11,820 devices such as these could be phones Servers typically have IP addresses configured statically because 14 00:01:11,820 --> 00:01:14,250 you need to connect to that server. 15 00:01:14,250 --> 00:01:21,990 So as an example if you go to Facebook dot com or some other Web site that domain name needs to be resolved 16 00:01:22,020 --> 00:01:27,930 to an IP address and you need to connect to a specific IP address or range of IP addresses and they 17 00:01:27,930 --> 00:01:35,520 are statically defined but more often than not client devices are automatically configured or dynamically 18 00:01:35,520 --> 00:01:41,120 configured because it's too much work to manually configure these devices. 19 00:01:41,160 --> 00:01:45,170 I mean when was the last time you manually configured your phone with an IP address. 20 00:01:45,180 --> 00:01:51,360 Most of us probably have never done that or only in exceptional circumstances with Internet of Things 21 00:01:51,360 --> 00:01:56,190 devices such as these lights or devices like cameras. 22 00:01:56,190 --> 00:02:04,080 It doesn't make sense to manually configure IP addresses so as an example here's a IP camera. 23 00:02:04,080 --> 00:02:08,940 I'm probably not going to configure this device statically. 24 00:02:09,120 --> 00:02:15,960 I'm going to let it dynamically be configured now DHB or Dynamic Host Configuration Protocol is once 25 00:02:15,960 --> 00:02:19,050 again a fundamental building block in networks today. 26 00:02:19,950 --> 00:02:23,230 Okay but how does DCP actually work. 27 00:02:23,250 --> 00:02:29,400 Do you know the messages sent between what's called a client and a server. 28 00:02:29,400 --> 00:02:32,280 Do you know how they work in this video. 29 00:02:32,280 --> 00:02:36,890 I'm gonna show you practically how to configure and use HP. 30 00:02:36,930 --> 00:02:38,270 I've got a network here. 31 00:02:38,400 --> 00:02:44,590 I'm going to demonstrate the HP using a router which I'll configure as a DHB server. 32 00:02:44,610 --> 00:02:51,540 This is a Cisco wrote it but the same principles apply whether you configuring a home router or some 33 00:02:51,540 --> 00:02:54,550 other kind of device as your DSP server. 34 00:02:54,570 --> 00:03:00,450 I've got a Windows P.C. and I've got a Linux P.C. that are going to get IP addresses from the router 35 00:03:00,780 --> 00:03:07,400 and I'm gonna run wire shock in this topology to show you how DHB actually works. 36 00:03:07,410 --> 00:03:10,310 So rather than just talking about it I'm going to demonstrate it. 37 00:03:10,680 --> 00:03:16,500 Here's an example of someone just talking about what the HP is rather than practically demonstrating 38 00:03:16,500 --> 00:03:17,330 it. 39 00:03:17,490 --> 00:03:27,210 Alexa what is DHEA P in computer networking the Dynamic Host Configuration Protocol D.H.. 40 00:03:27,310 --> 00:03:34,690 The network application protocol used by devices THC P clients to obtain configuration information for 41 00:03:34,690 --> 00:03:38,820 operation in an Internet protocol network okay. 42 00:03:38,830 --> 00:03:41,600 Not sure if you understood any of that but there you go. 43 00:03:41,660 --> 00:03:45,510 There's a so-called definition of DHEA. 44 00:03:45,730 --> 00:03:49,960 It's gonna make a lot more sense however if I show you this practically. 45 00:03:49,960 --> 00:03:51,930 Now she did mention some terms there. 46 00:03:51,940 --> 00:03:55,110 So let's look at some of those on this iPhone. 47 00:03:55,210 --> 00:03:58,300 If I go to Settings go to my Wi-Fi network. 48 00:03:58,300 --> 00:04:02,740 So in this example it's ABC 1 Top 5 gigahertz. 49 00:04:02,740 --> 00:04:09,880 Go and look at the information I can see firstly that the address has been allocated automatically rather 50 00:04:09,880 --> 00:04:14,400 than manually boot P is the predecessor to DCP. 51 00:04:14,500 --> 00:04:15,850 It wouldn't worry about that. 52 00:04:15,850 --> 00:04:22,510 Two main ways to configure IP addresses dynamically or automatically if you prefer that term or statically 53 00:04:22,620 --> 00:04:27,580 where you manually configure the IP address on the device notice we have an IP address. 54 00:04:27,590 --> 00:04:31,120 In this example it's 1 9 2 1 6 8 1 eleven. 55 00:04:31,340 --> 00:04:35,620 We have a subnet mask 255 255 255 0. 56 00:04:35,630 --> 00:04:45,200 We have a router 1 9 2 1 6 8 1 2 49 that is also known as the default gateway or the way to get to the 57 00:04:45,200 --> 00:04:46,170 Internet. 58 00:04:46,220 --> 00:04:49,880 So for a lot of people they don't understand necessarily the technical terms here. 59 00:04:49,880 --> 00:04:54,190 They just want Wi-Fi and Wi-Fi equates to Internet. 60 00:04:54,320 --> 00:04:57,190 So that's obviously not the same thing. 61 00:04:57,200 --> 00:05:01,520 Wi-Fi is the way that we connect to a network using wireless technologies. 62 00:05:01,550 --> 00:05:04,940 The Internet is a totally different concept and I won't discuss that right now. 63 00:05:05,060 --> 00:05:12,080 But basically the broader or the default gateway is the way that you get typically to the Internet notice 64 00:05:12,080 --> 00:05:18,350 we've got this option renew lease D.A. cheap IP addresses are typically only allocated for a period 65 00:05:18,350 --> 00:05:25,580 of time when you configure the DHB server you as the administrator decide how long a lease is so you 66 00:05:25,580 --> 00:05:28,960 can say the loss for three days or for a week. 67 00:05:29,090 --> 00:05:34,580 You typically don't want to allocate IP addresses permanently even though you can in certain cases because 68 00:05:34,640 --> 00:05:39,860 devices change as an example when you go to Starbucks you're not gonna be there permanently you're only 69 00:05:39,860 --> 00:05:47,390 going there for a period of time a DHB pool or scope typically only consists of a range of IP addresses 70 00:05:47,430 --> 00:05:53,530 so they may be only terms of 50 IP addresses in the pool or in the scope as people come and go. 71 00:05:53,630 --> 00:05:59,720 We want to reuse those IP addresses so we only want to allocate them for a period of time at Starbucks 72 00:05:59,720 --> 00:06:03,760 or other places they may reduce that interval to a much smaller period of time. 73 00:06:03,890 --> 00:06:07,000 So that addresses are reused more often. 74 00:06:07,040 --> 00:06:10,690 Notice this option configured DNS automatic or manual. 75 00:06:10,700 --> 00:06:18,840 In this example the DNS server is the local router 1 9 2 1 6 8 1 249 that could be configured as 8 8 76 00:06:18,930 --> 00:06:20,270 8 8 8 8 8. 77 00:06:20,290 --> 00:06:27,150 That's a Google DNS server quite a famous one that once again is configured by the DHB administrator. 78 00:06:27,490 --> 00:06:33,930 So that's an example of DHEA p on a client a phone. 79 00:06:34,130 --> 00:06:42,950 We have many devices that use DHEA p i o t or Internet of Things devices such as these typically don't 80 00:06:42,950 --> 00:06:47,420 get configured statically or manually it's too much work to configure it manually. 81 00:06:47,420 --> 00:06:49,260 You're gonna want to do it dynamically. 82 00:06:49,460 --> 00:06:55,870 This device as an example gives me a indication of the air quality in this room. 83 00:06:55,970 --> 00:07:04,940 So my iPhone using IP is connecting to the information from that device so that I can see how good the 84 00:07:04,940 --> 00:07:07,230 air quality is in the room. 85 00:07:07,310 --> 00:07:13,890 I can talk to an Alexa Alexa start CCN a quiz. 86 00:07:13,910 --> 00:07:16,830 Welcome to David bongos CCMA quiz. 87 00:07:16,850 --> 00:07:21,500 I will ask you twenty four questions try to get as many right as you can. 88 00:07:21,500 --> 00:07:23,210 Just say the number with the answer. 89 00:07:23,600 --> 00:07:24,830 Let's begin. 90 00:07:24,830 --> 00:07:29,260 Question 1 which of the following directions does T.P.. 91 00:07:29,300 --> 00:07:32,020 Okay let's play again soon. 92 00:07:32,420 --> 00:07:40,400 So that device has been allocated an IP address by DCP that's connecting through Wi-Fi no physical ethernet 93 00:07:40,400 --> 00:07:43,640 cables yet to the Internet. 94 00:07:43,640 --> 00:07:45,530 So going to the default gateway. 95 00:07:45,960 --> 00:07:46,200 Okay. 96 00:07:46,210 --> 00:07:52,490 So without further ado I'm gonna show you practically how to configure DHEA P now and show you how it 97 00:07:52,490 --> 00:07:54,560 actually works. 98 00:07:54,560 --> 00:08:00,050 Okay so in this topology I've turned off the windows P.C. and the linux host I want to configure the 99 00:08:00,050 --> 00:08:05,750 right of first and then once I've configured the right I want to run y shock on this link so that you 100 00:08:05,750 --> 00:08:15,650 can see the DHEA message so you can see the entire thing happening I guess he hits the to show IPD HP 101 00:08:16,400 --> 00:08:24,890 let's look at some options binding at the moment there are no bindings we haven't configured an address 102 00:08:24,910 --> 00:08:34,240 pull yet an address pull in subscript terminology is very similar to a scope on say Windows or a another 103 00:08:34,240 --> 00:08:40,940 platform I'm basically gonna create a pool of addresses and I'm gonna give it a name let's call it P.C.. 104 00:08:41,170 --> 00:08:50,060 This could be any name I'm gonna specify the network that is gonna be allocated and the subnet mask. 105 00:08:50,110 --> 00:08:56,710 Now don't worry if you aren't used to Cisco commands similar kind of principles apply no matter what 106 00:08:56,800 --> 00:08:58,180 device you're working on. 107 00:08:58,180 --> 00:08:59,360 He I've got a home right. 108 00:08:59,380 --> 00:09:01,230 This is a Beatty home router. 109 00:09:01,840 --> 00:09:06,300 I'm based in the UK so British Telecom is my service provider. 110 00:09:06,310 --> 00:09:09,610 This is the device that connects me to the Internet. 111 00:09:09,610 --> 00:09:17,880 If I go to advance settings here on this device make this a bit bigger and go to home network and go 112 00:09:17,880 --> 00:09:19,590 to it IP addresses. 113 00:09:19,830 --> 00:09:26,820 What you'll see here is this is the IP address of the router so that would typically be my default gateway 114 00:09:27,150 --> 00:09:32,340 if I connected to the wireless network or Wi-Fi network on this device. 115 00:09:32,340 --> 00:09:40,410 There's the subnet mask the DHB server is enabled and I've manually configured a range of addresses 116 00:09:40,770 --> 00:09:47,150 and I've specified the least time so last time in this case is three days. 117 00:09:47,340 --> 00:09:52,200 Typically a host will try and renew its IP address halfway through the least time. 118 00:09:52,200 --> 00:09:59,310 So that's an example on a home router in this example a British Telecom router on Cisco right as you 119 00:09:59,310 --> 00:10:05,450 typically are going to use the CLIA or command line interface to configure the devices so the network 120 00:10:05,480 --> 00:10:15,110 is once again this network that's similar in concept to specifying a range of addresses the way Cisco 121 00:10:15,120 --> 00:10:21,600 could do it is you specify the network and then you specify what's called an exclusion range of addresses 122 00:10:21,600 --> 00:10:23,020 that you want to exclude. 123 00:10:23,040 --> 00:10:28,350 So typically you're going to want to exclude the routers IP address from the pool and perhaps other 124 00:10:28,350 --> 00:10:30,640 network devices that you've got. 125 00:10:30,660 --> 00:10:30,880 Okay. 126 00:10:30,890 --> 00:10:35,730 So default gateway or default rather will be the local rider. 127 00:10:35,880 --> 00:10:38,560 That's the IP address of the local rider. 128 00:10:38,580 --> 00:10:42,860 I'll specify the DNS server as the local rider as well. 129 00:10:42,870 --> 00:10:48,810 Now I know that IP address because I've configured this rider to use this IP address. 130 00:10:48,990 --> 00:10:56,430 So I've basically configured show run shows me the configuration of the Cisco rider I've configured 131 00:10:56,460 --> 00:10:59,920 the Cisco rider with a DHB pull. 132 00:10:59,970 --> 00:11:01,460 This is the network. 133 00:11:01,620 --> 00:11:04,540 This is the default rider or default gateway. 134 00:11:04,560 --> 00:11:10,920 This is the DNS server very similar to this being the IP address of my B.T. rider. 135 00:11:10,950 --> 00:11:15,850 This is the subnet mask that's being used and these are the addresses that are being allocated. 136 00:11:15,900 --> 00:11:18,780 Now I haven't specified a least time I could do that. 137 00:11:18,780 --> 00:11:23,700 So IPD HP pool P.C. many options are available here. 138 00:11:23,730 --> 00:11:30,870 Many commands can be configured so I could specify lease and then specified number of days if I wanted 139 00:11:30,870 --> 00:11:32,910 to or specify infinite. 140 00:11:32,970 --> 00:11:37,060 Be careful with infinite because you could use up your pool of addresses. 141 00:11:37,060 --> 00:11:44,220 So I'll just specify this time of one day I could specify a domain name as an example of let's say that. 142 00:11:44,220 --> 00:11:45,960 So David bumbled dot com. 143 00:11:45,960 --> 00:11:56,130 If I go back one step I could say IPD HP excluded addresses and let's exclude the router from the address 144 00:11:56,130 --> 00:11:57,210 pool. 145 00:11:57,270 --> 00:12:05,330 So on the right to show IPD HP pool I have configured a pool of addresses the pools name is P.C.. 146 00:12:05,580 --> 00:12:09,850 Total addresses in the pool is this. 147 00:12:10,000 --> 00:12:12,220 This is the addresses in the address pool. 148 00:12:12,220 --> 00:12:19,840 No addresses have been the least at the moment show run once again shows us that IP addresses in this 149 00:12:19,840 --> 00:12:26,520 range will be allocated but this one won't default wrote a DNS of a domain name. 150 00:12:26,530 --> 00:12:32,500 Okay so let's start y Ashok on the link between the switch and the router. 151 00:12:32,800 --> 00:12:34,680 So why Sugar's running. 152 00:12:35,320 --> 00:12:44,770 I can see various protocols here you can see as an example CTP spanning tree a bunch of protocols but 153 00:12:44,770 --> 00:12:48,380 I'm gonna filter for the HP because I only want to see the HP messages. 154 00:12:49,120 --> 00:12:52,770 Okay what I'll do is start the windows host first. 155 00:12:53,020 --> 00:12:58,050 So this Windows piece is actually running as a virtual machine in my topology. 156 00:12:58,180 --> 00:12:59,610 I'm running on a Mac here. 157 00:12:59,770 --> 00:13:07,030 Genius 3 is a way for me to virtualize networks and I'm virtualizing a network of a Cisco rod a switch 158 00:13:07,420 --> 00:13:09,790 a linux host and a Windows P.C.. 159 00:13:09,830 --> 00:13:20,210 So P.C. has booted up a logging I'm going to start a CRM deep prompt 160 00:13:24,850 --> 00:13:30,620 and I'll make this bigger so that it's easier to read so IP config. 161 00:13:31,630 --> 00:13:39,050 And I'm thinking Linux there should be IP conflict not I have config So IP config notice I can see domain 162 00:13:39,050 --> 00:13:45,390 name I can see IP address that was allocated I can see subnet mask default gateway. 163 00:13:45,410 --> 00:13:51,050 Now the reason this piece he used that address and not 10 1 1 1 is because that address was allocated 164 00:13:51,050 --> 00:13:57,080 previously and it's just trying to get to the same IP address so IP address has been allocated I can 165 00:13:57,080 --> 00:14:02,060 use the common IP config slash all to see more information. 166 00:14:02,060 --> 00:14:08,210 So scrolling up again there's the command this is the hostname. 167 00:14:08,210 --> 00:14:13,570 Now notice it's called M.S. age 110 that becomes important when we look at the why shock capture is 168 00:14:13,580 --> 00:14:20,900 the domain name we can see the MAC address of the P.C. so this is the MAC address burnt into the network 169 00:14:20,930 --> 00:14:29,340 interface call it I could see that as an example by going to control panel network and Internet view 170 00:14:29,340 --> 00:14:34,650 network status look at my network interface card. 171 00:14:34,740 --> 00:14:41,430 Notice if I click on details I'll be able to see the physical IP address and IP address information 172 00:14:41,430 --> 00:14:44,220 in a similar way to using IP config. 173 00:14:44,790 --> 00:14:55,010 I can also see when I go to properties that I'm using DHB obtain IP address automatically obtain DNS 174 00:14:55,160 --> 00:15:01,100 server information automatically and using the IP conflict slash all command. 175 00:15:01,280 --> 00:15:04,940 I can see IP address subnet mask. 176 00:15:05,060 --> 00:15:10,310 Notice default gateway and DNS server information shown in the output here.