1 00:00:07,050 --> 00:00:09,990 - [Lecturer] A switch is a central connecting device 2 00:00:09,990 --> 00:00:14,160 that all computers connect to in a wired fashion. 3 00:00:14,160 --> 00:00:18,600 This is a design known as a Star Topology. 4 00:00:18,600 --> 00:00:20,880 A switch sends the signal, 5 00:00:20,880 --> 00:00:22,800 the frames of data, 6 00:00:22,800 --> 00:00:26,520 to the correct computer on the correct port. 7 00:00:26,520 --> 00:00:30,420 And it does this by identifying the MAC address 8 00:00:30,420 --> 00:00:32,220 of each computer. 9 00:00:32,220 --> 00:00:36,960 This can effectively make every port an individual entity. 10 00:00:36,960 --> 00:00:39,090 So here we have a switch, 11 00:00:39,090 --> 00:00:43,410 and let's say we had a computer connected to Port 1. 12 00:00:43,410 --> 00:00:45,730 You would connect with a patch cable 13 00:00:46,980 --> 00:00:49,710 and an RJ45 plug on the end. 14 00:00:49,710 --> 00:00:51,750 And when you do so and connect the other end 15 00:00:51,750 --> 00:00:52,893 to the computer, 16 00:00:54,717 --> 00:00:56,430 you'll see that connectivity, 17 00:00:56,430 --> 00:00:59,400 the LED, the link light will light up on the switch, 18 00:00:59,400 --> 00:01:04,080 and it'll light up on the computer's network interface card. 19 00:01:04,080 --> 00:01:05,640 If we add other computers connected, 20 00:01:05,640 --> 00:01:07,053 and that's the whole point, 21 00:01:08,190 --> 00:01:10,650 let's say we had other computers connected here, 22 00:01:10,650 --> 00:01:13,830 those computers can all communicate with each other 23 00:01:13,830 --> 00:01:15,303 via the switch. 24 00:01:16,350 --> 00:01:21,350 Now, switches employ a matrix of copper wiring, 25 00:01:21,450 --> 00:01:26,010 instead of just a trunk circuit in older hubs. 26 00:01:26,010 --> 00:01:27,480 So these have a matrix 27 00:01:27,480 --> 00:01:29,970 so every port can communicate 28 00:01:29,970 --> 00:01:33,870 with every other port simultaneously. 29 00:01:33,870 --> 00:01:35,970 They're also intelligent, 30 00:01:35,970 --> 00:01:40,470 and they use this intelligence to pass information 31 00:01:40,470 --> 00:01:42,093 to the correct port. 32 00:01:43,740 --> 00:01:47,670 This means that each computer has its own bandwidth. 33 00:01:47,670 --> 00:01:50,670 For example, 1000 megabits per second. 34 00:01:50,670 --> 00:01:54,840 You might also see 10 gigabit per second connections. 35 00:01:54,840 --> 00:01:57,780 And you might also see these written sometimes, 36 00:01:57,780 --> 00:02:02,780 as say, 1000MB and a slash, and an S. 37 00:02:04,320 --> 00:02:05,850 And that's the same thing, though. 38 00:02:05,850 --> 00:02:08,340 That's gonna be the same as Mbps. 39 00:02:08,340 --> 00:02:11,249 I use this terminology, this measurement, 40 00:02:11,249 --> 00:02:13,560 because some of the big companies like Cisco 41 00:02:13,560 --> 00:02:15,270 use these quite often. 42 00:02:15,270 --> 00:02:18,030 So quite often, you'll see 1000 megabits per second, 43 00:02:18,030 --> 00:02:22,173 which is 1 gigabits per second. 44 00:02:23,760 --> 00:02:26,850 And also 10 gigabit per second networks. 45 00:02:26,850 --> 00:02:30,270 You might also see 100 megabit per second connections, 46 00:02:30,270 --> 00:02:31,680 older connections, 47 00:02:31,680 --> 00:02:34,470 but you'll probably want to upgrade those switches 48 00:02:34,470 --> 00:02:35,763 if you do see those. 49 00:02:36,780 --> 00:02:41,460 Switches work within the Ethernet standard. 50 00:02:41,460 --> 00:02:44,820 That's the most common networking standard used today, 51 00:02:44,820 --> 00:02:47,670 and it was ratified by the IEEE. 52 00:02:47,670 --> 00:02:52,670 And it's documented in the 802.3 set of standards. 53 00:02:54,510 --> 00:02:57,810 For example, a typical Ethernet network 54 00:02:57,810 --> 00:03:00,810 running at 1000 megabits per second 55 00:03:00,810 --> 00:03:03,990 and using twisted pair cable 56 00:03:03,990 --> 00:03:08,990 is classified as 802.3ab. 57 00:03:09,420 --> 00:03:11,730 And if it's running at 10 gigabits per second, 58 00:03:11,730 --> 00:03:14,850 again, over twisted pair cable TP, 59 00:03:14,850 --> 00:03:17,707 then it would be known as 802.3an. 60 00:03:18,810 --> 00:03:22,953 But they're all within the 802.3 Ethernet standards. 61 00:03:24,300 --> 00:03:27,600 Quite often, multiple switches will be used, 62 00:03:27,600 --> 00:03:31,140 'cause you can only connect so many computers to one switch. 63 00:03:31,140 --> 00:03:33,903 In this example, we can only connect 16 systems. 64 00:03:35,790 --> 00:03:37,920 You can get switches with more ports. 65 00:03:37,920 --> 00:03:41,100 You can get 24, 48, 96 and so on, 66 00:03:41,100 --> 00:03:44,490 but at some point you're gonna get to a max. 67 00:03:44,490 --> 00:03:46,410 So quite often what you'll see, 68 00:03:46,410 --> 00:03:48,690 is you'll see the switches connected 69 00:03:48,690 --> 00:03:50,700 in a hierarchical fashion. 70 00:03:50,700 --> 00:03:51,533 And what that means 71 00:03:51,533 --> 00:03:54,150 is you'll have computers connecting to a switch, 72 00:03:54,150 --> 00:03:55,980 computers connecting to another switch, 73 00:03:55,980 --> 00:03:57,600 computers connecting to another switch, 74 00:03:57,600 --> 00:04:00,240 as many switches as you need for those systems. 75 00:04:00,240 --> 00:04:03,963 And then those switches will connect to a master switch. 76 00:04:05,520 --> 00:04:08,313 So we have the Star Topology, 77 00:04:10,320 --> 00:04:13,830 where computers are connected to a switch, 78 00:04:13,830 --> 00:04:15,870 and the switch is the central connecting device 79 00:04:15,870 --> 00:04:17,610 for those computers. 80 00:04:17,610 --> 00:04:20,820 But then we do this in a hierarchical fashion 81 00:04:20,820 --> 00:04:24,003 where each of these switches connects to a master switch. 82 00:04:25,620 --> 00:04:26,940 So that's very common. 83 00:04:26,940 --> 00:04:31,500 Let's take a look at a switch that I have here. 84 00:04:31,500 --> 00:04:33,483 And this is a Cisco SG200. 85 00:04:35,190 --> 00:04:37,140 So we're gonna log into this guy now 86 00:04:37,140 --> 00:04:38,790 and you do that through the browser. 87 00:04:38,790 --> 00:04:40,230 Now, in the A+ exams, 88 00:04:40,230 --> 00:04:43,470 you're not gonna need to know Cisco commands 89 00:04:43,470 --> 00:04:44,303 and the command line, 90 00:04:44,303 --> 00:04:46,410 like the Show commands and things like that. 91 00:04:46,410 --> 00:04:47,490 I'm gonna show you a switch 92 00:04:47,490 --> 00:04:49,470 that's operated from the GUI. 93 00:04:49,470 --> 00:04:51,680 Now, you'll notice here that I connected by IP address, 94 00:04:51,680 --> 00:04:55,050 10.252.0.240 within the browser. 95 00:04:55,050 --> 00:04:57,120 And it says it's not secure, 96 00:04:57,120 --> 00:04:58,530 so keep that in mind. 97 00:04:58,530 --> 00:05:00,003 So we'll log in now. 98 00:05:04,710 --> 00:05:06,210 And notice that you can log in, 99 00:05:06,210 --> 00:05:10,500 or you can log in with secure browsing, HTTPS. 100 00:05:10,500 --> 00:05:12,900 Really we don't even want that option. 101 00:05:12,900 --> 00:05:15,600 So we're gonna show how to turn that on, 102 00:05:15,600 --> 00:05:18,120 so it only does secure browsing. 103 00:05:18,120 --> 00:05:19,950 But right now we're gonna log on 104 00:05:19,950 --> 00:05:22,530 in an insecure fashion, so to speak. 105 00:05:22,530 --> 00:05:24,240 And so the first thing I wanna show here, 106 00:05:24,240 --> 00:05:26,100 you can see there's lots of configuration 107 00:05:26,100 --> 00:05:27,630 that you can do here, 108 00:05:27,630 --> 00:05:28,830 but let's look at the basics. 109 00:05:28,830 --> 00:05:31,590 I wanna show the IP address configuration screen 110 00:05:31,590 --> 00:05:33,120 for this switch. 111 00:05:33,120 --> 00:05:34,773 So we'll go to Administration, 112 00:05:36,540 --> 00:05:38,163 Management Interface, 113 00:05:39,360 --> 00:05:42,753 and IP version 4 Interface. 114 00:05:44,580 --> 00:05:48,930 When we do that, we see the IP address of this switch. 115 00:05:48,930 --> 00:05:50,763 And that is what we connected to. 116 00:05:52,080 --> 00:05:53,220 Now you have two options here, 117 00:05:53,220 --> 00:05:55,440 you have Dynamic and Static. 118 00:05:55,440 --> 00:05:58,470 A Dynamic address means that switch will look out 119 00:05:58,470 --> 00:06:01,380 to the network for a DHCP server 120 00:06:01,380 --> 00:06:03,720 to obtain an IP address automatically. 121 00:06:03,720 --> 00:06:07,530 Generally with switches and servers and things like that 122 00:06:07,530 --> 00:06:09,090 you don't really want to go that way 123 00:06:09,090 --> 00:06:11,250 unless you have a lot of switches. 124 00:06:11,250 --> 00:06:14,760 So if you have one switch or a couple switches, or several, 125 00:06:14,760 --> 00:06:17,580 Static is the better way to go so that you know, 126 00:06:17,580 --> 00:06:19,650 and you can do documentation on this 127 00:06:19,650 --> 00:06:23,250 specifying what switch uses which IP address. 128 00:06:23,250 --> 00:06:24,390 And that's what I've done here, 129 00:06:24,390 --> 00:06:27,630 I've made it Static and set it to .240. 130 00:06:27,630 --> 00:06:30,840 And there's all kinds of other information here. 131 00:06:30,840 --> 00:06:33,750 You can create additional user accounts. 132 00:06:33,750 --> 00:06:35,253 You have a system log. 133 00:06:37,410 --> 00:06:39,933 Diagnostics, and so on, and so on. 134 00:06:41,790 --> 00:06:43,230 One thing that you'll get into more 135 00:06:43,230 --> 00:06:45,570 if you get into the Network+ and Security+ 136 00:06:45,570 --> 00:06:47,520 would be VLAN Management, 137 00:06:47,520 --> 00:06:52,080 Spanning Tree, and especially, Security. 138 00:06:52,080 --> 00:06:53,780 Now let's take a look at Security. 139 00:06:55,500 --> 00:06:57,030 Lots of stuff here. 140 00:06:57,030 --> 00:07:00,510 And we'll go to TCP/UDP Services. 141 00:07:00,510 --> 00:07:05,510 And here we see we have the option to connect via HTTP 142 00:07:05,940 --> 00:07:08,460 and HTTPS. 143 00:07:08,460 --> 00:07:09,420 And if you look down here 144 00:07:09,420 --> 00:07:12,180 we do have an HTTP connection to this address. 145 00:07:12,180 --> 00:07:16,470 The local address is .240 from .254. 146 00:07:16,470 --> 00:07:18,480 That's the workstation I'm working at, 147 00:07:18,480 --> 00:07:21,210 using inbound port 80. 148 00:07:21,210 --> 00:07:23,310 So that's what we kind of don't really want, 149 00:07:23,310 --> 00:07:27,803 we want to connect to this in a secure fashion with HTTPS. 150 00:07:29,610 --> 00:07:33,240 So to only connect via 443, 151 00:07:33,240 --> 00:07:36,480 instead of connecting on 80, to only use HTTPS, 152 00:07:36,480 --> 00:07:40,020 we'd have to disable HTTP and then apply that. 153 00:07:40,020 --> 00:07:42,060 Now, before we could do that 154 00:07:42,060 --> 00:07:45,660 we would have to actually have a valid certificate 155 00:07:45,660 --> 00:07:49,500 and have that set up in the SSL Server section. 156 00:07:49,500 --> 00:07:52,410 That takes a little bit of doing with the Cisco switch, 157 00:07:52,410 --> 00:07:55,410 and it's really beyond the scope of the A+ exam, 158 00:07:55,410 --> 00:07:56,700 but that's what you'd wanna do 159 00:07:56,700 --> 00:08:01,290 so that we could just have HTTPS and connect in the browser 160 00:08:01,290 --> 00:08:04,683 with a valid certificate and get that padlock. 161 00:08:05,580 --> 00:08:09,240 Other than that, you could also use SSH, 162 00:08:09,240 --> 00:08:11,430 and you could configure that for connectivity, 163 00:08:11,430 --> 00:08:14,400 and you have your user and server authentication here. 164 00:08:14,400 --> 00:08:17,700 So there's a lot of options when it comes to security, 165 00:08:17,700 --> 00:08:20,730 but that's a little bit about the switch here. 166 00:08:20,730 --> 00:08:22,740 Now, I showed before, 167 00:08:22,740 --> 00:08:26,163 if you have these switches connected in this manner, 168 00:08:27,240 --> 00:08:30,690 you have a hierarchical connection. 169 00:08:30,690 --> 00:08:33,060 But what if someone 170 00:08:33,060 --> 00:08:35,850 was to connect these two switches together, 171 00:08:35,850 --> 00:08:38,160 or these two switches together? 172 00:08:38,160 --> 00:08:42,060 Then we could have a loop, 173 00:08:42,060 --> 00:08:43,260 and the information 174 00:08:43,260 --> 00:08:45,780 would constantly be going round and round in circles 175 00:08:45,780 --> 00:08:49,230 because of that secondary connection between the switches. 176 00:08:49,230 --> 00:08:51,660 So you wanna avoid looping, 177 00:08:51,660 --> 00:08:54,180 and to do that you implement 178 00:08:54,180 --> 00:08:59,180 something known as Spanning Tree Protocol, that's STP. 179 00:08:59,790 --> 00:09:02,370 And that could be found here, Spanning Tree, 180 00:09:02,370 --> 00:09:04,560 and we'll go to STP status, 181 00:09:04,560 --> 00:09:05,640 and you wanna make sure 182 00:09:05,640 --> 00:09:08,250 that the Spanning Tree Protocol is enabled, 183 00:09:08,250 --> 00:09:11,070 and generally that's set to Rapid STP. 184 00:09:11,070 --> 00:09:16,070 So even if someone was to connect these switches 185 00:09:16,860 --> 00:09:19,590 in a physical manner, in a secondary fashion, 186 00:09:19,590 --> 00:09:21,030 and it creates a loop, 187 00:09:21,030 --> 00:09:23,880 that loop would be blocked by STP. 188 00:09:23,880 --> 00:09:27,210 So that's a little bit about network switches. 189 00:09:27,210 --> 00:09:31,050 And the cool thing about this SG200, 190 00:09:31,050 --> 00:09:32,220 if you-- 191 00:09:32,220 --> 00:09:33,960 I'm actually using a physical box, 192 00:09:33,960 --> 00:09:37,440 but this is available as an emulator 193 00:09:37,440 --> 00:09:39,810 on the internet from Cisco. 194 00:09:39,810 --> 00:09:41,670 So you can check that out for free also, 195 00:09:41,670 --> 00:09:43,980 and check out some of the configurations. 196 00:09:43,980 --> 00:09:44,813 All right, 197 00:09:44,813 --> 00:09:46,170 so definitely take a look at that, 198 00:09:46,170 --> 00:09:47,400 and take a look at any switching 199 00:09:47,400 --> 00:09:51,666 that you might have in your household or in your network, 200 00:09:51,666 --> 00:09:55,230 if you have rights and permissions to do so, 201 00:09:55,230 --> 00:09:58,200 and learn a little bit more about network switching. 202 00:09:58,200 --> 00:09:59,950 And that's about it for this video.