1 00:00:00,060 --> 00:00:02,400 Assigning IP addresses. 2 00:00:02,400 --> 00:00:03,900 Now, when we have our networks 3 00:00:03,900 --> 00:00:06,660 and they rely on IP addresses like IPV4, 4 00:00:06,660 --> 00:00:08,760 how do we tell our devices what addresses 5 00:00:08,760 --> 00:00:09,990 they're going to have? 6 00:00:09,990 --> 00:00:12,480 Well, there are really two different methods we can use. 7 00:00:12,480 --> 00:00:15,090 One is to manually or statically assign them 8 00:00:15,090 --> 00:00:17,400 and the other is to dynamically assign them. 9 00:00:17,400 --> 00:00:19,050 Now, when I use a static assignment, 10 00:00:19,050 --> 00:00:20,910 this is a really simple process. 11 00:00:20,910 --> 00:00:21,810 As a technician, 12 00:00:21,810 --> 00:00:24,630 I manually will type in the IP address for the host, 13 00:00:24,630 --> 00:00:28,050 its subnet mask, its default gateway, and its DNS server. 14 00:00:28,050 --> 00:00:31,080 But this can be time consuming and prone to error. 15 00:00:31,080 --> 00:00:34,050 For example, let's say I have 20 devices on the network. 16 00:00:34,050 --> 00:00:35,400 Now I'm going to have to go and assign 17 00:00:35,400 --> 00:00:37,110 those four pieces of information 18 00:00:37,110 --> 00:00:39,540 20 different times, once for each device. 19 00:00:39,540 --> 00:00:41,940 That's 80 places I have to enter information. 20 00:00:41,940 --> 00:00:44,790 This means there's a lot of chance for human error here 21 00:00:44,790 --> 00:00:47,040 because these numbers are very easy to mistype, 22 00:00:47,040 --> 00:00:48,720 and if you mistype one, 23 00:00:48,720 --> 00:00:50,430 you're going to be assigning the wrong information 24 00:00:50,430 --> 00:00:53,940 to the wrong devices, or you might have the same information 25 00:00:53,940 --> 00:00:56,820 on multiple devices and this will also cause problems 26 00:00:56,820 --> 00:00:58,980 or conflicts between two devices. 27 00:00:58,980 --> 00:01:02,160 So as you start to work on large enterprise networks, 28 00:01:02,160 --> 00:01:04,769 it becomes very impractical to do static assignment 29 00:01:04,769 --> 00:01:07,440 of the IP addresses for all your devices. 30 00:01:07,440 --> 00:01:09,390 Some of our networks in the past that I've run 31 00:01:09,390 --> 00:01:11,910 have been 500 clients, 1,000 clients, 32 00:01:11,910 --> 00:01:15,180 5,000 clients, 10,000 clients, 100,000 clients, 33 00:01:15,180 --> 00:01:17,820 or even 1 million client computers 34 00:01:17,820 --> 00:01:19,590 in a large scale intranet. 35 00:01:19,590 --> 00:01:21,660 So for us to assign those all statically 36 00:01:21,660 --> 00:01:24,060 and keep track of all those different IP addresses 37 00:01:24,060 --> 00:01:27,060 would become a full-time job for a large team of people 38 00:01:27,060 --> 00:01:28,560 located all over the world 39 00:01:28,560 --> 00:01:30,673 because that large intranet spans six continents. 40 00:01:30,673 --> 00:01:33,810 That would be a waste of a lot of time, money, 41 00:01:33,810 --> 00:01:35,610 labor, and resources. 42 00:01:35,610 --> 00:01:38,400 So instead, we simplify this process 43 00:01:38,400 --> 00:01:41,190 by using dynamic allocation of IP addresses. 44 00:01:41,190 --> 00:01:43,440 This is known as a dynamic assignment. 45 00:01:43,440 --> 00:01:45,750 By doing this, we have a quicker, easier, 46 00:01:45,750 --> 00:01:48,420 and less confusing method of assigning our Ips 47 00:01:48,420 --> 00:01:51,330 to all of our network clients when they join the network. 48 00:01:51,330 --> 00:01:53,130 Now for large or small networks, 49 00:01:53,130 --> 00:01:54,510 using dynamic IP addressing 50 00:01:54,510 --> 00:01:56,970 is usually going to be your best option. 51 00:01:56,970 --> 00:01:58,950 In your home, whether or not you know it, 52 00:01:58,950 --> 00:02:01,680 you're already probably using dynamic IP addressing. 53 00:02:01,680 --> 00:02:03,120 When you bought a new smartphone 54 00:02:03,120 --> 00:02:05,070 or tablet or laptop or desktop, 55 00:02:05,070 --> 00:02:07,080 you took it out of the box, you powered it on, 56 00:02:07,080 --> 00:02:08,759 and then you joined your wireless network 57 00:02:08,759 --> 00:02:11,340 and you were able to go online and browse the web, right? 58 00:02:11,340 --> 00:02:13,680 You didn't have to do any kind of crazy configurations. 59 00:02:13,680 --> 00:02:16,200 Well, in this case, you didn't assign your new device 60 00:02:16,200 --> 00:02:18,960 an IP address, a subnet mask, a default gateway, 61 00:02:18,960 --> 00:02:20,670 or a DNS server to use. 62 00:02:20,670 --> 00:02:23,670 Instead, your network's DHCP server did all that for you 63 00:02:23,670 --> 00:02:26,610 automatically without you even having to ask it to. 64 00:02:26,610 --> 00:02:28,740 This is because most small office and home office 65 00:02:28,740 --> 00:02:30,810 network devices like your cable modem, 66 00:02:30,810 --> 00:02:32,850 fiber modem, or wireless access point, 67 00:02:32,850 --> 00:02:35,400 already have a running DHCP server there for you, 68 00:02:35,400 --> 00:02:37,110 and it's turned on by default. 69 00:02:37,110 --> 00:02:39,120 You just tell the device what network to join 70 00:02:39,120 --> 00:02:40,770 and your router will use DHCP 71 00:02:40,770 --> 00:02:42,540 to hand out a dynamic IP address 72 00:02:42,540 --> 00:02:44,880 for your network client to be able to utilize. 73 00:02:44,880 --> 00:02:46,710 So what are those four components 74 00:02:46,710 --> 00:02:48,330 of a fully configured client? 75 00:02:48,330 --> 00:02:50,370 Well, whether you're using static or dynamic assignment, 76 00:02:50,370 --> 00:02:53,160 you still need to use the same four components. 77 00:02:53,160 --> 00:02:56,910 This is an IP address, a subnet mask, a default gateway, 78 00:02:56,910 --> 00:02:58,890 which is usually just the IP of your router, 79 00:02:58,890 --> 00:03:01,620 and a server for either DNS or WINS. 80 00:03:01,620 --> 00:03:04,290 Now DNS is the domain name system. 81 00:03:04,290 --> 00:03:06,480 DNS is going to be used to convert domain names 82 00:03:06,480 --> 00:03:09,480 used by a website to the IP address of its server 83 00:03:09,480 --> 00:03:11,190 so that your computer can connect to it. 84 00:03:11,190 --> 00:03:14,130 For right now, just realize that DNS is essentially 85 00:03:14,130 --> 00:03:15,900 the internet's version of a phone book 86 00:03:15,900 --> 00:03:16,920 where we can look up a name 87 00:03:16,920 --> 00:03:19,170 and get a number to connect directly to. 88 00:03:19,170 --> 00:03:21,060 Now names to numbers and numbers to names, 89 00:03:21,060 --> 00:03:23,070 that's what DNS is all about. 90 00:03:23,070 --> 00:03:25,800 For example, when you went to diontraining.com, 91 00:03:25,800 --> 00:03:27,960 you're going to be using DNS in the background 92 00:03:27,960 --> 00:03:30,570 to determine what the IP address is of my server, 93 00:03:30,570 --> 00:03:32,610 so you can connect to it and access our webpages 94 00:03:32,610 --> 00:03:33,630 or our videos. 95 00:03:33,630 --> 00:03:35,460 That is DNS at work. 96 00:03:35,460 --> 00:03:38,190 Now WINS on the other hand, W-I-N-S, 97 00:03:38,190 --> 00:03:40,290 is used within a local area network. 98 00:03:40,290 --> 00:03:43,050 Specifically, WINS is used in Windows domains 99 00:03:43,050 --> 00:03:45,990 and it is known as the Windows Internet Name Service. 100 00:03:45,990 --> 00:03:47,580 It's used to enable Windows 101 00:03:47,580 --> 00:03:50,940 to identify net bios names on a TCP IP network 102 00:03:50,940 --> 00:03:53,970 and convert those NetBIOS names to IP addresses. 103 00:03:53,970 --> 00:03:56,070 Basically WINS is like DNS, 104 00:03:56,070 --> 00:03:59,160 but it only works within a Windows domain environment. 105 00:03:59,160 --> 00:04:01,080 So if I wanted to connect to my mail server 106 00:04:01,080 --> 00:04:02,520 inside a Windows domain, 107 00:04:02,520 --> 00:04:04,890 I could type in its IP address if I knew it, 108 00:04:04,890 --> 00:04:07,140 or I could simply type in the name of the server, 109 00:04:07,140 --> 00:04:10,020 something like Mailbox or whatever I have named it. 110 00:04:10,020 --> 00:04:12,090 Now, when it comes time to do the dynamic assignment 111 00:04:12,090 --> 00:04:14,880 of the critical addressing information for each client, 112 00:04:14,880 --> 00:04:17,370 we can use four different methods to do this. 113 00:04:17,370 --> 00:04:21,510 This includes BOOTP, DHCP, APIPA and ZeroConf. 114 00:04:21,510 --> 00:04:24,150 BOOTP is by far the oldest and least used 115 00:04:24,150 --> 00:04:25,650 of these four options. 116 00:04:25,650 --> 00:04:27,540 BOOTP or the Bootstrap protocol 117 00:04:27,540 --> 00:04:29,910 was originally introduced in 1985 118 00:04:29,910 --> 00:04:32,280 for use in diskless Unix workstations 119 00:04:32,280 --> 00:04:33,690 because it could dynamically assign 120 00:04:33,690 --> 00:04:34,980 the IP address information 121 00:04:34,980 --> 00:04:36,120 and then allow the workstation 122 00:04:36,120 --> 00:04:38,970 to load a copy of their boot image over the network. 123 00:04:38,970 --> 00:04:42,570 Now, BOOTP used a static database of IPs and MAC addresses. 124 00:04:42,570 --> 00:04:44,850 So essentially, whenever a client connected to the network 125 00:04:44,850 --> 00:04:46,650 to initiate the BOOTP process, 126 00:04:46,650 --> 00:04:49,140 it would find its Mac address inside its database 127 00:04:49,140 --> 00:04:51,330 and then send the proper IP address that matched it 128 00:04:51,330 --> 00:04:54,090 back to the requesting client as its assignment. 129 00:04:54,090 --> 00:04:57,240 This wasn't as dynamic as we would like so in 1993, 130 00:04:57,240 --> 00:05:00,060 a newer updated protocol known as DHCP 131 00:05:00,060 --> 00:05:02,520 was introduced to replace BOOTP. 132 00:05:02,520 --> 00:05:06,000 Now, DHCP or the Dynamic Host Configuration Protocol 133 00:05:06,000 --> 00:05:07,980 is going to allow the assignment of an IP 134 00:05:07,980 --> 00:05:11,010 based on an assigned scope or pool of addresses, 135 00:05:11,010 --> 00:05:13,050 as well as it provides the ability for us to configure 136 00:05:13,050 --> 00:05:15,030 numerous other options within it. 137 00:05:15,030 --> 00:05:17,610 Now, since DHCP allows me to configure my scope, 138 00:05:17,610 --> 00:05:20,040 I can actually tell my DHCP server something like, 139 00:05:20,040 --> 00:05:22,470 hey, I only want you to hand out addresses 140 00:05:22,470 --> 00:05:25,830 that are from 192.168.1.100 141 00:05:25,830 --> 00:05:29,097 up through 192.168.1.200, 142 00:05:29,097 --> 00:05:31,290 and this gives you about a hundred clients 143 00:05:31,290 --> 00:05:33,300 that can now be automatically assigned. 144 00:05:33,300 --> 00:05:35,070 Every time somebody connects to the network, 145 00:05:35,070 --> 00:05:38,220 the DHCP is going to send out one of those IPs from that range 146 00:05:38,220 --> 00:05:39,990 and assign it for a given period of time, 147 00:05:39,990 --> 00:05:42,150 known as a lease, to a client. 148 00:05:42,150 --> 00:05:44,160 Now each IP can be barred for a certain amount 149 00:05:44,160 --> 00:05:46,950 of time from this pool, and when that lease expires, 150 00:05:46,950 --> 00:05:49,740 the DHCP server is going to pull back that address. 151 00:05:49,740 --> 00:05:52,290 Now, this doesn't actually cause a problem for us 152 00:05:52,290 --> 00:05:54,330 because your computer at any time can say, 153 00:05:54,330 --> 00:05:56,100 hey, I'm still using that address. 154 00:05:56,100 --> 00:05:57,210 You can't take it. 155 00:05:57,210 --> 00:05:59,400 And in that case, the DHCP server would say, 156 00:05:59,400 --> 00:06:01,200 oh, okay, you can keep it 157 00:06:01,200 --> 00:06:04,650 and reassigns it for another period by renewing its lease. 158 00:06:04,650 --> 00:06:06,630 It's just like if you get a book from the library, 159 00:06:06,630 --> 00:06:08,040 say you are halfway through reading it 160 00:06:08,040 --> 00:06:10,020 and it's going to be due tomorrow, you could take it back 161 00:06:10,020 --> 00:06:11,880 to the library and recheck it out. 162 00:06:11,880 --> 00:06:15,270 It's the same concept with DHCP and dynamic addresses. 163 00:06:15,270 --> 00:06:16,950 Now, when the lease does expire 164 00:06:16,950 --> 00:06:18,690 and it's no longer needed by the client, 165 00:06:18,690 --> 00:06:21,300 it's going to be returned back to the scope or that pool 166 00:06:21,300 --> 00:06:23,490 and be ready to be issued to another client. 167 00:06:23,490 --> 00:06:25,860 Essentially, each client can borrow that IP 168 00:06:25,860 --> 00:06:27,600 during its assignment and then return it 169 00:06:27,600 --> 00:06:29,100 whenever it's done with it. 170 00:06:29,100 --> 00:06:31,170 Now this IP management is going to be performed 171 00:06:31,170 --> 00:06:33,600 by the DHCP server on our behalf, 172 00:06:33,600 --> 00:06:35,460 and it's going to be used to manage all of these IPs 173 00:06:35,460 --> 00:06:37,680 that are being assigned and returned over time. 174 00:06:37,680 --> 00:06:39,930 This is great because we don't have to control it ourself 175 00:06:39,930 --> 00:06:41,850 or keep track of it all manually. 176 00:06:41,850 --> 00:06:45,240 Instead, we have the ability to go into it at any time 177 00:06:45,240 --> 00:06:46,980 and look at the logs and say, hey, 178 00:06:46,980 --> 00:06:51,090 who was using the IP 192.168.1.132 179 00:06:51,090 --> 00:06:53,100 on September 9th at 3:00 PM 180 00:06:53,100 --> 00:06:55,380 and then we can figure it out using DHCP's 181 00:06:55,380 --> 00:06:57,750 IP address management and their logs. 182 00:06:57,750 --> 00:06:59,820 And so this gives us all the benefits of figuring out 183 00:06:59,820 --> 00:07:01,980 who did what while still not having to do 184 00:07:01,980 --> 00:07:03,600 any of the management and oversight 185 00:07:03,600 --> 00:07:05,700 of handing out these IP addresses. 186 00:07:05,700 --> 00:07:07,830 Now, another great thing about DHTP 187 00:07:07,830 --> 00:07:08,970 is that it gives our clients 188 00:07:08,970 --> 00:07:10,260 all of these different variables 189 00:07:10,260 --> 00:07:11,700 that they need to communicate. 190 00:07:11,700 --> 00:07:14,250 This includes the dynamic IP address that's being assigned, 191 00:07:14,250 --> 00:07:15,570 as well as the subnet mask, 192 00:07:15,570 --> 00:07:18,000 the default gateway, and the DNS server. 193 00:07:18,000 --> 00:07:19,620 And if you're using a WINS server, 194 00:07:19,620 --> 00:07:21,870 you can also send that through DHCP. 195 00:07:21,870 --> 00:07:24,750 This can all be done using the DHCP protocol for us 196 00:07:24,750 --> 00:07:27,630 automatically each and every time a new client connects 197 00:07:27,630 --> 00:07:28,860 to the network. 198 00:07:28,860 --> 00:07:31,770 Yes, I know I've repeated these four configuration options 199 00:07:31,770 --> 00:07:34,530 a bunch of times now, and you know what that means? 200 00:07:34,530 --> 00:07:37,200 It means this information is really important. 201 00:07:37,200 --> 00:07:40,170 So you simply have to know those four configuration items 202 00:07:40,170 --> 00:07:42,300 that DHCP provides to your clients 203 00:07:42,300 --> 00:07:44,370 and keep them in mind for test day. 204 00:07:44,370 --> 00:07:47,130 Remember, that's the IP address, the subnet mask, 205 00:07:47,130 --> 00:07:49,590 the gateway, and the DNS server's IP. 206 00:07:49,590 --> 00:07:51,450 The WINS server is an optional component 207 00:07:51,450 --> 00:07:53,220 that may or may not be sent. 208 00:07:53,220 --> 00:07:55,620 Alright, we're going to talk a lot more about DHCP 209 00:07:55,620 --> 00:07:57,660 in a separate video, but for now, 210 00:07:57,660 --> 00:08:00,600 you need to remember that DHCP is the modern implementation 211 00:08:00,600 --> 00:08:04,230 of BOOTP and it's commonly used in our modern networks 212 00:08:04,230 --> 00:08:06,810 to be able to assign automatically the IP address 213 00:08:06,810 --> 00:08:08,730 and other required data for a client 214 00:08:08,730 --> 00:08:10,470 to communicate on a network. 215 00:08:10,470 --> 00:08:12,150 Now, the third way we can do automatic 216 00:08:12,150 --> 00:08:16,080 or dynamic addressing is by using APIPA, A-P-I-P-A, 217 00:08:16,080 --> 00:08:19,260 or the Automatic Private Internet Protocol Addressing. 218 00:08:19,260 --> 00:08:21,390 Basically, if for any reason DHCP 219 00:08:21,390 --> 00:08:23,490 cannot complete the assignment process 220 00:08:23,490 --> 00:08:25,440 or find an address for you to give to the client 221 00:08:25,440 --> 00:08:26,670 because you ran out, 222 00:08:26,670 --> 00:08:29,190 then APIPA is going to be used instead. 223 00:08:29,190 --> 00:08:30,960 This kind of thing can happen if there's a problem 224 00:08:30,960 --> 00:08:33,120 where the client can't reach the DHCP server 225 00:08:33,120 --> 00:08:36,450 because of networking issues or something else like that. 226 00:08:36,450 --> 00:08:38,730 Now, in these cases, the client is going to assign itself 227 00:08:38,730 --> 00:08:41,850 an APIPA address, which is a self-assigned address. 228 00:08:41,850 --> 00:08:44,520 Now, by default on a Windows server or workstation, 229 00:08:44,520 --> 00:08:47,340 you're going to find that APIPA is selected by default 230 00:08:47,340 --> 00:08:49,290 under the TCP IP properties 231 00:08:49,290 --> 00:08:51,480 under the alternate configuration tab. 232 00:08:51,480 --> 00:08:53,280 Now, this allows the Windows machine 233 00:08:53,280 --> 00:08:55,410 to assign itself an address randomly 234 00:08:55,410 --> 00:08:59,040 from the 169.254 .something .something scope 235 00:08:59,040 --> 00:09:01,200 if it can't reach a DHTP server 236 00:09:01,200 --> 00:09:04,620 or it can't contact it and finish the negotiation process. 237 00:09:04,620 --> 00:09:07,410 Now, APIPA is designed to allow for a quick configuration 238 00:09:07,410 --> 00:09:08,820 of a local area network 239 00:09:08,820 --> 00:09:11,400 without the need of having a DHTP server. 240 00:09:11,400 --> 00:09:13,290 For example, if I take 10 clients 241 00:09:13,290 --> 00:09:16,200 and I connect them all to a switch without a DHCP server, 242 00:09:16,200 --> 00:09:17,790 these 10 clients will default 243 00:09:17,790 --> 00:09:20,820 to picking up their own IP address from the APIPA range, 244 00:09:20,820 --> 00:09:24,330 which is 169.254 .something .something. 245 00:09:24,330 --> 00:09:26,460 Again, because it's a Class B address, 246 00:09:26,460 --> 00:09:27,840 this is perfectly fine 247 00:09:27,840 --> 00:09:30,630 because they're all going to be on the same local area network. 248 00:09:30,630 --> 00:09:32,760 So if I wanted to play "Doom" on this local area network 249 00:09:32,760 --> 00:09:34,740 with these 10 machines, that's fine. 250 00:09:34,740 --> 00:09:35,730 They'll all find each other 251 00:09:35,730 --> 00:09:38,010 and they'll talk based on their APIPA addresses 252 00:09:38,010 --> 00:09:39,780 without any issues at all. 253 00:09:39,780 --> 00:09:41,400 Now, the only problem that will occur 254 00:09:41,400 --> 00:09:43,320 is that these are private IP addresses, 255 00:09:43,320 --> 00:09:46,680 so they can't be read outside of our local area network. 256 00:09:46,680 --> 00:09:48,870 Therefore, if we need to communicate locally, 257 00:09:48,870 --> 00:09:51,690 we can do that using a switch and everything will be fine, 258 00:09:51,690 --> 00:09:54,000 but we're not going to be able to reach the internet 259 00:09:54,000 --> 00:09:56,880 because we don't have the same network as the router. 260 00:09:56,880 --> 00:09:58,920 Because the router had a valid IP address, 261 00:09:58,920 --> 00:10:00,330 not an APIPA address. 262 00:10:00,330 --> 00:10:02,370 And so we don't have a default gateway to get out 263 00:10:02,370 --> 00:10:04,530 of this local network we've created. 264 00:10:04,530 --> 00:10:06,510 Now, this is the biggest challenge you're going to have 265 00:10:06,510 --> 00:10:08,910 when you have an APIPA address assigned to your clients 266 00:10:08,910 --> 00:10:10,170 because they cannot communicate 267 00:10:10,170 --> 00:10:11,760 outside the local area network 268 00:10:11,760 --> 00:10:14,970 or with other devices that don't have an IP address as well. 269 00:10:14,970 --> 00:10:16,230 If you ever have a computer that starts 270 00:10:16,230 --> 00:10:19,380 with 169.254 .something .something, 271 00:10:19,380 --> 00:10:21,090 and you can't figure out why it's not connecting 272 00:10:21,090 --> 00:10:23,610 to the internet, well that's your reason. 273 00:10:23,610 --> 00:10:24,690 It's an APIPA address 274 00:10:24,690 --> 00:10:27,420 and APIPA addresses can't get out past the router, 275 00:10:27,420 --> 00:10:29,370 and so APIPA addresses are not going to allow you 276 00:10:29,370 --> 00:10:30,780 to connect to the internet. 277 00:10:30,780 --> 00:10:33,480 Our last dynamic method of configuring an IP address 278 00:10:33,480 --> 00:10:36,390 is known as ZeroConf or zero configuration. 279 00:10:36,390 --> 00:10:38,490 Now ZeroConf is a newer technology 280 00:10:38,490 --> 00:10:40,350 that was based on APIPA and can provide you 281 00:10:40,350 --> 00:10:42,390 with a lot of the same features as APIPA, 282 00:10:42,390 --> 00:10:43,800 as well as some new ones. 283 00:10:43,800 --> 00:10:47,040 For example, ZeroConf can actually assign an IPV4 284 00:10:47,040 --> 00:10:48,870 link-local address to a client. 285 00:10:48,870 --> 00:10:51,090 This is a form of a non-routable IP 286 00:10:51,090 --> 00:10:54,060 that's used on a local subnet just like APIPA. 287 00:10:54,060 --> 00:10:56,550 But the big difference is that with zero config, 288 00:10:56,550 --> 00:10:57,960 this client can now have the ability 289 00:10:57,960 --> 00:11:00,420 to resolve computer names to IP addresses 290 00:11:00,420 --> 00:11:04,230 without the need of DNS by using something known as mDNS 291 00:11:04,230 --> 00:11:06,750 or multicast Domain Name Service. 292 00:11:06,750 --> 00:11:09,570 Also, ZeroConf can perform a service discovery 293 00:11:09,570 --> 00:11:11,910 on a network so it can find out what things are connected 294 00:11:11,910 --> 00:11:13,110 and available for use. 295 00:11:13,110 --> 00:11:14,610 So if there's a printer, a scanner, 296 00:11:14,610 --> 00:11:15,990 or shared file system, 297 00:11:15,990 --> 00:11:18,600 you can actually find that using ZeroConf. 298 00:11:18,600 --> 00:11:20,430 There have been lots of different implementations 299 00:11:20,430 --> 00:11:22,410 of ZeroConf in recent years, 300 00:11:22,410 --> 00:11:23,700 and it's called different things 301 00:11:23,700 --> 00:11:24,930 depending on the implementation 302 00:11:24,930 --> 00:11:26,550 and the product line you're using. 303 00:11:26,550 --> 00:11:28,410 For example, on Apple Products, 304 00:11:28,410 --> 00:11:30,720 ZeroConf is actually called Bonjour, 305 00:11:30,720 --> 00:11:33,270 and it's used mostly for service discovery of other clients 306 00:11:33,270 --> 00:11:35,490 and devices on the local area network. 307 00:11:35,490 --> 00:11:36,780 In Microsoft Windows, 308 00:11:36,780 --> 00:11:39,300 they like to call it LLMNR, 309 00:11:39,300 --> 00:11:41,760 Link-Local Multicast Name Resolution, 310 00:11:41,760 --> 00:11:43,650 and it's going to rely on it as an extension 311 00:11:43,650 --> 00:11:45,780 of APIPA to provide for name resolution 312 00:11:45,780 --> 00:11:47,820 and service discovery in addition to providing 313 00:11:47,820 --> 00:11:49,260 network connectivity. 314 00:11:49,260 --> 00:11:50,400 Now, if you're using Linux, 315 00:11:50,400 --> 00:11:53,340 ZeroConf is usually implemented using SystemD, 316 00:11:53,340 --> 00:11:55,110 or the system daemon service, 317 00:11:55,110 --> 00:11:58,890 specifically the systemd-resolved background service. 318 00:11:58,890 --> 00:12:01,350 So remember, there are lots of different ways 319 00:12:01,350 --> 00:12:02,880 to assign IP addresses. 320 00:12:02,880 --> 00:12:05,280 You can do it manually known as a static assignment 321 00:12:05,280 --> 00:12:08,520 or automatically known as a dynamic assignment. 322 00:12:08,520 --> 00:12:10,200 If you're using a dynamic assignment, 323 00:12:10,200 --> 00:12:12,240 you can do this with one of four methods, 324 00:12:12,240 --> 00:12:15,720 BOOTP, DHTP, APIPA, or ZeroConf. 325 00:12:15,720 --> 00:12:18,270 Really, it all depends on the needs of your clients 326 00:12:18,270 --> 00:12:19,233 and your network.