1 00:00:00,494 --> 00:00:06,407 In this video, we are going to start learning about vlan. So what is vlan? 2 00:00:06,685 --> 00:00:09,159 And why we need a vlan? 3 00:00:10,428 --> 00:00:19,865 We will learn with an example case. Here let’s say we have a room. And in this room we have 9 pc. 4 00:00:20,386 --> 00:00:23,896 all of this pc is connected to a switch. 5 00:00:24,995 --> 00:00:33,733 These 9 pc is separated to different division. These 3 pc is in accounting division, 6 00:00:34,268 --> 00:00:42,512 these 3 pc is in the engineering division, and last, these 3 pc is in the marketing division. 7 00:00:43,520 --> 00:00:47,722 Usually, each division will have different services. 8 00:00:48,407 --> 00:00:53,539 Let’s say engineering division need higher bandwidth than others division. 9 00:00:54,030 --> 00:01:02,021 Or let’s say marketing division is allowed to access social media like facebook, instagram, or others, 10 00:01:02,595 --> 00:01:07,076 but others division is prohibited to access social media. 11 00:01:08,115 --> 00:01:12,320 Because each division need different services like that, 12 00:01:12,320 --> 00:01:20,376 so we will need to configure vlan for each division. Let’s say for accounting we use vlan 10, 13 00:01:20,626 --> 00:01:30,317 engineering use vlan 20, and marketing use vlan 30. So each division will use different vlan. 14 00:01:31,071 --> 00:01:36,449 And then, each vlan will use different network or different block subnet. 15 00:01:36,960 --> 00:01:46,866 Let’s say vlan accounting or vlan 10, will use 192.168.10.0/24, for engineering or vlan 16 00:01:46,866 --> 00:02:03,381 20 will use 192.168.20.0/24, and finally for marketing or vlan 30 will use 192.168.30.0/24. 17 00:02:04,306 --> 00:02:09,280 If each division using different vlan and different network like this, 18 00:02:09,280 --> 00:02:11,952 we can easily manage the service. 19 00:02:13,276 --> 00:02:19,764 Here let’s complete the topology. So from the switch must be connected to a router, 20 00:02:20,146 --> 00:02:24,074 and from router must be connected to internet like this. 21 00:02:24,963 --> 00:02:33,095 Now let’s say we want to only allow access social media from marketing division, to do that we can 22 00:02:33,095 --> 00:02:44,469 create a firewall or access list in the router to allow access to social media from 192.168.30.0/24, 23 00:02:44,960 --> 00:02:47,521 and block access from the others. 24 00:02:48,963 --> 00:02:53,489 Okay, so that is the first advantage of using vlan. 25 00:02:54,146 --> 00:03:01,381 The second advantage that we can get if using vlan is separation of broadcast domain. 26 00:03:02,024 --> 00:03:11,952 Let’s say here we have PC 1, and here we have PC 2. When PC 1 want to send packet to PC 2, 27 00:03:12,365 --> 00:03:22,004 first PC1 will send ARP packet to the switch. This ARP packet is used to ask the mac address of PC 2. 28 00:03:22,734 --> 00:03:26,501 After switch receive the ARP packet from PC 1, 29 00:03:26,727 --> 00:03:31,243 switch will broadcast the ARP packet to all pc connected to it. 30 00:03:32,195 --> 00:03:40,202 But because now we already have vlan, so the ARP packet from PC1 will not sent to other vlan, 31 00:03:40,487 --> 00:03:48,432 but only sent to the computer that is in the same vlan with PC 1, which is PC 2 and PC 3. 32 00:03:49,360 --> 00:03:54,255 The ARP packet will not sent to PC in the vlan 10 and vlan 20. 33 00:03:55,224 --> 00:04:02,794 Okay, so this is the second advantage of using vlan, which is separation of broadcast domain. 34 00:04:03,426 --> 00:04:08,125 Okay I think enough for this video, I hope you understand what is vlan 35 00:04:08,125 --> 00:04:11,310 and why we need to configure a vlan. 36 00:04:11,645 --> 00:04:15,130 Thankyou for watching and see you on the next video!