1 00:00:00,680 --> 00:00:01,310 Some switch. 2 00:00:01,310 --> 00:00:06,080 One, we're going to shut this interface down to force traffic to go via the hub. 3 00:00:06,920 --> 00:00:08,400 So interface gigabit. 4 00:00:08,420 --> 00:00:08,750 Zero. 5 00:00:08,750 --> 00:00:10,190 To shut it down. 6 00:00:11,390 --> 00:00:13,070 Show interface gigabit. 7 00:00:13,220 --> 00:00:14,060 Zero three. 8 00:00:14,060 --> 00:00:14,870 Switch port. 9 00:00:16,650 --> 00:00:22,050 The support gigabyte zero three is acting as a trunk using editor one q. 10 00:00:22,560 --> 00:00:24,120 All VLANs are allowed. 11 00:00:25,270 --> 00:00:29,770 So let's do a capture on The Hub. 12 00:00:31,140 --> 00:00:35,340 We were receiving previous information and notice the difference here. 13 00:00:35,370 --> 00:00:37,890 He has an attitude and one q header. 14 00:00:38,100 --> 00:00:40,080 So we have ethernet. 15 00:00:40,350 --> 00:00:50,640 But notice the type is not IP version for the type is ed to one Q so the type is 0x8 100 rather than 16 00:00:50,640 --> 00:00:53,640 0x0 800 for IP. 17 00:00:53,850 --> 00:00:55,560 So 83 one keyframe. 18 00:00:56,220 --> 00:01:02,010 We can see here that the VLAN ID for this previous RT message is VLAN. 19 00:01:02,010 --> 00:01:09,960 One per VLAN spanning tree sends what are called PDAs on every VLAN. 20 00:01:10,290 --> 00:01:12,720 So here we can see some spanning tree information. 21 00:01:13,620 --> 00:01:21,540 And as we scroll down, we can see that as an example, CDP and HTTP messages or in this case, HTTP 22 00:01:21,660 --> 00:01:27,330 is sent as an untagged frame so we can see some HTTP information arriving here. 23 00:01:28,630 --> 00:01:30,070 And that will continue on. 24 00:01:30,400 --> 00:01:31,940 So let's do a ping. 25 00:01:33,060 --> 00:01:43,440 From rather to acting as PC to to write a for and see if we can see why the frames are not permitted. 26 00:01:46,600 --> 00:01:48,610 So ICMP is showing nothing. 27 00:01:49,610 --> 00:01:51,490 So we can see a broadcast here. 28 00:01:51,500 --> 00:01:57,410 This is an op message saying who has ten one, two, four. 29 00:01:58,010 --> 00:01:58,820 So. 30 00:02:00,210 --> 00:02:02,400 In this OP message. 31 00:02:03,810 --> 00:02:06,030 And I'll just stop that capture for a moment. 32 00:02:06,660 --> 00:02:07,650 Here's the op. 33 00:02:08,419 --> 00:02:11,240 You can see it's an Ethernet two frame. 34 00:02:12,020 --> 00:02:13,190 With a broad cost. 35 00:02:13,190 --> 00:02:15,890 So the destination is a broad cost source. 36 00:02:15,890 --> 00:02:18,650 MAC address is the MAC address of router two. 37 00:02:19,310 --> 00:02:22,010 We can see that by looking at the interface. 38 00:02:22,010 --> 00:02:24,470 So show interface if zero. 39 00:02:24,470 --> 00:02:25,580 Slash zero. 40 00:02:27,210 --> 00:02:29,730 Notice there's the Mac address of the router. 41 00:02:30,710 --> 00:02:33,590 And there it is shown in the why shock capture. 42 00:02:34,130 --> 00:02:41,180 But notice the type is once again ETA 2 to 1 Q And the VLAN is set to VLAN two. 43 00:02:41,970 --> 00:02:48,330 So in other words, the router is sending the frame untagged to the switch. 44 00:02:48,690 --> 00:02:53,820 But when it goes across this link, it's going as a tagged frame. 45 00:02:54,300 --> 00:03:02,250 The switch is setting the VLAN tag to two because it arrived on this port which is in VLAN two. 46 00:03:02,880 --> 00:03:05,040 I'm just reset that capture. 47 00:03:06,960 --> 00:03:08,730 And what I want to show you is. 48 00:03:11,130 --> 00:03:13,780 On this port is going to show us untagged. 49 00:03:13,800 --> 00:03:19,920 So it's standard Ethernet, but on this one it's going to show us tagged because the switch is tagging 50 00:03:19,920 --> 00:03:20,580 the frame. 51 00:03:24,850 --> 00:03:26,200 So I'll do the ping again. 52 00:03:29,290 --> 00:03:34,390 Now this is the frame to the switch from the router and we'll do a search for ARP. 53 00:03:34,870 --> 00:03:39,070 You can see there's the op traffic from. 54 00:03:40,280 --> 00:03:42,800 The router to a broadcast address. 55 00:03:43,070 --> 00:03:44,270 It's untagged. 56 00:03:44,840 --> 00:03:46,370 This is the type for app. 57 00:03:46,520 --> 00:03:49,430 There is no ADA 2 to 1 q header here at all. 58 00:03:50,690 --> 00:03:59,360 But when we look for ARP on the link between the switches, notice you can see the ADA 2 to 1 CU tag 59 00:03:59,360 --> 00:04:00,440 set to two. 60 00:04:03,910 --> 00:04:05,290 So the traffic. 61 00:04:06,730 --> 00:04:12,670 Is arriving here is untagged and the switch is tagging it to send the frame to switch to. 62 00:04:12,700 --> 00:04:18,820 The problem here is when the traffic hits switch to switch to is not configured with trunking. 63 00:04:19,180 --> 00:04:21,490 This is just an access port in VLAN one. 64 00:04:22,620 --> 00:04:29,130 So that traffic will be sent onto this port but not out of this port which is in VLAN two. 65 00:04:30,700 --> 00:04:36,910 So let's switch to let's see if we can see that show interface trunk. 66 00:04:37,030 --> 00:04:39,520 At the moment, no interfaces are trunking. 67 00:04:39,610 --> 00:04:42,970 Show interface gigabit zero three. 68 00:04:44,400 --> 00:04:46,590 And let's put switch port at the end. 69 00:04:48,000 --> 00:04:50,140 So show interfaces gigabit. 70 00:04:50,200 --> 00:04:51,690 Zero three switch port. 71 00:04:52,650 --> 00:04:55,410 This interface gigabit zero three is enabled. 72 00:04:55,680 --> 00:05:02,430 It's set for negotiation of trunking, so it's in a VLAN one. 73 00:05:02,700 --> 00:05:05,550 This port belongs to VLAN one. 74 00:05:06,480 --> 00:05:07,890 It's an access port. 75 00:05:08,100 --> 00:05:14,280 No trunking is enabled, so traffic from router two is simply going to be sent out of this port. 76 00:05:14,280 --> 00:05:16,380 So let's do a CAPTCHA there to prove that. 77 00:05:18,930 --> 00:05:23,550 And then we'll do a CAPTCHA on this port to check if any traffic arrives on this port. 78 00:05:24,240 --> 00:05:25,920 So there's the Wireshark capture. 79 00:05:26,400 --> 00:05:28,470 Do the ping again on router two. 80 00:05:28,980 --> 00:05:30,060 I'll do a. 81 00:05:30,790 --> 00:05:31,870 Full time for OP. 82 00:05:31,870 --> 00:05:37,930 I notice there's the broadcast traffic from ten 1 to 2, which is rather to. 83 00:05:40,520 --> 00:05:43,610 Asking for the Mac address of ten 1 to 4. 84 00:05:44,000 --> 00:05:49,250 So rather two is asking for the MAC address of root of four, but it never receives it. 85 00:05:49,490 --> 00:05:54,230 So what you'll also notice here is there is no editor or one Q Tag. 86 00:05:54,710 --> 00:05:57,590 So the frame was sent untagged here. 87 00:05:57,620 --> 00:06:01,700 It was sent tagged across here, arrived here. 88 00:06:01,880 --> 00:06:06,560 But this port was configured as an access port in VLAN one, so the traffic was simply copied out of 89 00:06:06,560 --> 00:06:09,200 this port in VLAN one with no tag. 90 00:06:09,410 --> 00:06:11,390 The traffic never arrived on this port. 91 00:06:12,020 --> 00:06:14,450 So let's prove that to a captcha here. 92 00:06:17,840 --> 00:06:21,890 We'll do the ping again and try and falter for up. 93 00:06:23,060 --> 00:06:30,320 And what you'll notice is there's no traffic because the traffic is arriving on an access port, port 94 00:06:30,320 --> 00:06:30,940 one. 95 00:06:30,950 --> 00:06:34,230 It's only going to be sent out of this port, which is port one. 96 00:06:34,280 --> 00:06:36,380 It's not going to be sent out of this port at all. 97 00:06:37,010 --> 00:06:38,660 So let's stop all captures. 98 00:06:40,140 --> 00:06:45,000 And then what we'll do now is configure this port to be a trunk port and this port would be a trunk 99 00:06:45,000 --> 00:06:45,570 port. 100 00:06:45,600 --> 00:06:51,120 But we'll leave this port shut down for the moment so that we can see the traffic being captured.