WEBVTT 00:01.840 --> 00:04.600 This is what this is Dmvpn. 00:08.080 --> 00:10.090 Phase one. 00:11.140 --> 00:16.720 But before we go to phase one, before we go to the MVP and phase one, we still have to understand 00:16.720 --> 00:18.880 what an M is. 00:20.380 --> 00:21.340 What is a multi point? 00:22.630 --> 00:26.910 Do you remember yesterday we talked about tunnels. 00:28.600 --> 00:31.270 We talked about how tunnels were scalable. 00:31.900 --> 00:33.820 Much more than crypto maps. 00:34.690 --> 00:35.110 Right. 00:35.320 --> 00:41.080 If you compare that to a multi point guy, there is a huge difference. 00:42.010 --> 00:43.270 What do I mean by that? 00:43.520 --> 00:52.180 N is different than a normal guy in a sense that in the guy that we did yesterday, even though we still 00:52.180 --> 00:57.880 have that confusion of the header size, which is not an issue because you're still reducing overhead 00:59.590 --> 01:08.870 in the guy that we did had a router here, which was R1, it had one tunnel with R2 and I had to create 01:08.870 --> 01:09.830 a separate tunnel. 01:11.810 --> 01:14.570 Without the different addresses. 01:14.570 --> 01:17.900 So this was 168.1.1. 01:17.900 --> 01:24.020 This was .2.1 or 2.0 slash 24 slash 24. 01:24.230 --> 01:31.520 So as many number of peers, you have as many number of tunnels you would require with different addresses. 01:32.180 --> 01:33.370 Same is the concept here. 01:33.380 --> 01:35.840 Now, R2 and R3 wants to communicate to each other. 01:35.870 --> 01:39.740 They could have done it through R1, but that would be too much load on R1. 01:40.880 --> 01:44.210 So what they would do is they would create another tunnel between themselves. 01:46.430 --> 01:48.230 Certain from R1 to R2. 01:48.410 --> 01:53.620 A tunnel from R1 to R3, then R3 to R2, a separate budget. 01:53.780 --> 01:55.430 Solve the issue of scalability. 01:57.470 --> 01:59.060 It does to some extent. 01:59.060 --> 02:01.570 But now imagine scalability means what? 02:01.580 --> 02:06.830 The more the devices come in, the more scalable means, the more easier it gets. 02:07.520 --> 02:10.940 But now imagine if I have R4 coming into the same picture. 02:12.260 --> 02:23.600 R4 would require one tunnel for full communication, one with him, one with him, one with him three. 02:24.620 --> 02:24.920 Right. 02:25.550 --> 02:27.020 R1 has another one now. 02:27.650 --> 02:28.780 Another guy comes in. 02:28.790 --> 02:31.340 R5 more tunnels. 02:31.340 --> 02:38.330 One, two, three, four, five, six comes in. 02:38.360 --> 02:39.470 He would require five. 02:40.400 --> 02:42.250 R7 comes in, he would require seven. 02:42.260 --> 02:42.770 Sorry. 02:42.800 --> 02:44.420 Five, six, seven, eight, nine. 02:44.420 --> 02:45.050 Like that. 02:45.980 --> 02:48.740 Each guy would require the total number of him. 02:48.740 --> 02:53.450 For example, R6 less than one and minus one is five times. 02:54.350 --> 02:55.280 Each guy. 02:58.130 --> 02:58.870 Five tons. 02:59.090 --> 03:00.800 So our five is connected like that. 03:00.800 --> 03:02.600 Our one will be also connected like that. 03:03.290 --> 03:04.850 Our four will be connected like that. 03:05.000 --> 03:06.500 Our two will be connected by itself. 03:06.500 --> 03:11.270 So by complicated the situation can get tricky. 03:12.830 --> 03:15.770 The more you expand, the more difficult it becomes. 03:15.770 --> 03:16.040 Yes. 03:16.040 --> 03:18.320 For three four sites. 03:18.350 --> 03:19.010 Okay. 03:19.730 --> 03:21.560 What about you have 200 sites. 03:22.190 --> 03:27.650 How do you manage those with these tunnels with having different IP addresses for every different connection 03:27.650 --> 03:28.400 that you have? 03:30.510 --> 03:30.890 Right. 03:30.900 --> 03:33.870 So it is scalable only to some extent. 03:34.650 --> 03:40.020 We want to increase that scalability to up to at least 2000 spokes. 03:43.130 --> 03:43.340 Right. 03:43.510 --> 03:43.880 How? 03:48.370 --> 03:53.530 Jerry came up with a new concept which was known as multipoint zero. 03:54.280 --> 03:58.540 When you look at a tunnel now, you don't look at a tunnel from a point to point perspective. 03:58.690 --> 04:02.620 Now you look at it from this perspective. 04:03.220 --> 04:05.740 One, two, three, four, five. 04:07.880 --> 04:08.150 They? 04:11.680 --> 04:12.130 Similarly. 04:12.880 --> 04:18.490 Similarly, yes, if you want to look at it from from the surface, that's how it looks like. 04:18.850 --> 04:23.340 But we'll go deeply into the details of how it works. 04:23.350 --> 04:25.030 From the surface, it looks like a switch. 04:25.030 --> 04:29.290 So 192 168 1.0 slash 24 will be your main tunnel. 04:29.800 --> 04:36.480 Then your end points will be .1.2.3.4.. 04:36.670 --> 04:40.660 This will be our main aim to create something like this. 04:41.620 --> 04:44.890 A tunnel which looks like this looks weird, doesn't it? 04:46.020 --> 04:47.860 We know how source and destination works. 04:47.860 --> 04:49.000 How is this going to work out? 04:51.540 --> 04:53.090 As this whole concept we're going to work on. 04:54.420 --> 04:57.180 We'll see before that, just keep this in mind. 04:57.540 --> 04:58.710 Let's configure this. 04:58.740 --> 05:04.860 Now, the best way to configure topology like this is also the easiest way. 05:05.850 --> 05:08.490 Interface zero zero IP address is one five. 05:09.250 --> 05:10.350 16:00. 05:14.150 --> 05:15.040 You need it out. 05:15.260 --> 05:15.740 Bit out. 05:20.810 --> 05:29.300 Winning gold 66, which is the Internet, also would require a loopback to the IP address of ten 111. 05:31.080 --> 05:32.110 Because that is the whole point. 05:32.130 --> 05:36.990 Eventually, I don't want the hubs, all these devices to talk to each other. 05:37.020 --> 05:39.160 I want networks behind them to talk to each other. 05:39.180 --> 05:39.660 Right. 05:43.290 --> 05:44.400 Starting from hour one. 05:47.540 --> 05:48.940 Then I too. 05:48.950 --> 05:50.000 Similar config. 05:51.290 --> 05:52.400 26.2. 05:52.430 --> 05:54.260 Next stop is 26.6. 05:54.470 --> 05:55.490 Loopback is. 05:58.210 --> 05:58.580 Conduct. 06:03.300 --> 06:08.670 13333. 06:11.020 --> 06:11.380 And 06:14.800 --> 06:15.160 I thought. 06:26.880 --> 06:29.530 We are is open for any mistake that I might make. 06:41.370 --> 06:42.600 Finally R6. 06:43.980 --> 06:45.810 R6 I'm going to configure separately. 06:48.520 --> 06:49.840 I need to see the interface. 06:56.020 --> 06:59.230 0001 50 .1.6.6. 07:09.740 --> 07:12.810 Zero 130 6.6. 07:16.940 --> 07:17.900 Zero three. 07:20.710 --> 07:21.390 46. 07:33.690 --> 07:34.320 Finally. 07:48.670 --> 07:52.190 Let's set from R2 generated 26.2. 07:56.030 --> 08:04.040 Can't can can it reach 36.3 can 46.4. 08:05.060 --> 08:06.710 I hope you have it on your diagrams. 08:08.450 --> 08:14.540 56.5 So you can visualize the whole concept about VPNs is you should be able to visualize. 08:16.700 --> 08:17.510 You can see it. 08:18.770 --> 08:19.460 You can do it. 08:20.270 --> 08:22.090 Try to visualize how a packet is going. 08:22.100 --> 08:22.790 Going. 08:22.880 --> 08:27.170 As a graphical representation in your head, try to imagine the packet flow. 08:30.210 --> 08:31.170 That's enough wisdom. 08:33.120 --> 08:33.960 Moving forward. 08:35.100 --> 08:39.540 What we have is I want to go to R1. 08:40.950 --> 08:42.540 I want to create a tunnel from R1. 08:43.770 --> 08:47.040 This is going to be a multi point tunnel, right? 08:47.070 --> 08:53.040 So when I do my interface Channel zero here, my IP address part is going to be the same. 08:53.040 --> 08:54.860 192 168 1.1. 08:56.730 --> 09:00.510 My tunnel source is going to be the same, which is 151 .6.1. 09:03.270 --> 09:10.500 My tunnel destination is not going to be the same because if I choose my tunnel destination, that means 09:10.500 --> 09:11.040 what? 09:13.050 --> 09:14.730 I've already planned it, right? 09:15.510 --> 09:17.430 I've already planned the other end point of the tunnel. 09:17.460 --> 09:18.270 Do I want that? 09:18.270 --> 09:18.570 No. 09:19.440 --> 09:20.310 One side. 09:20.310 --> 09:22.650 Remember, the first side is static. 09:22.680 --> 09:26.430 The other side is going to be that big circle that I created open. 09:28.520 --> 09:29.780 So there is no tunnel. 09:30.140 --> 09:32.580 Destination tunnel mode. 09:32.600 --> 09:34.160 By default, the mode is what? 09:38.990 --> 09:41.870 By default, it's zero or IP. 09:42.620 --> 09:43.610 By default. 09:45.220 --> 09:46.730 We are going to do what? 09:50.790 --> 09:57.870 The problem with this multipoint is now you have to manually tell him what are the other end points? 10:00.940 --> 10:02.140 What are the other end points? 10:02.170 --> 10:03.760 See where the problem comes in. 10:07.300 --> 10:07.900 Not a problem. 10:07.900 --> 10:09.610 We talked about it yesterday too. 10:09.640 --> 10:11.380 Let's say I can figure this. 10:15.420 --> 10:20.730 This is 192 168 1.0 slash 24. 10:22.320 --> 10:23.520 This is dot one. 10:24.420 --> 10:25.320 This is dot two. 10:25.890 --> 10:28.350 Let's talk about these two and maybe dot three. 10:30.890 --> 10:32.520 When I want to send a packet. 10:36.390 --> 10:40.830 Which originates from 1.1 going to 1.2. 10:40.860 --> 10:41.850 1.2168. 10:41.880 --> 10:43.350 1.12192168. 10:43.350 --> 10:44.010 1.2. 10:44.190 --> 10:46.650 It gets encapsulated using what? 10:50.280 --> 10:52.410 What public header source do I use? 10:56.840 --> 10:57.980 What about the destination? 11:03.450 --> 11:04.500 What about the destination? 11:05.100 --> 11:05.850 Yesterday. 11:05.850 --> 11:07.650 How did I get this destination from? 11:09.120 --> 11:10.050 It was specified. 11:10.080 --> 11:11.310 Tunnel source was specified. 11:11.340 --> 11:12.890 Tunnel destination was specified. 11:12.900 --> 11:13.310 So I. 11:13.320 --> 11:14.910 New tunnel source was 16.1. 11:14.940 --> 11:16.860 Tunnel destination would be 26.2. 11:17.190 --> 11:19.300 So just forward the packet to 26.2. 11:20.040 --> 11:21.180 Today that is the problem. 11:21.180 --> 11:22.650 I don't have the destination. 11:23.820 --> 11:27.450 I have my source outside source destination part is missing. 11:27.720 --> 11:29.730 But I know that this tunnel is what. 11:32.820 --> 11:34.890 I know that the tunnel is Mgr. 11:36.150 --> 11:37.980 How do I solve the destination part? 11:41.500 --> 11:42.070 Remember this. 11:42.070 --> 11:46.300 If you understand this, you understand Dmvpn, Right. 11:46.390 --> 11:49.990 Also, the other challenge is if I want to go to 1.3. 11:53.060 --> 11:54.820 192 168 1.35. 11:55.010 --> 11:56.570 Want to go to the 1.3. 11:56.870 --> 11:57.890 End point of the tunnel. 11:58.610 --> 11:59.810 What do I use here? 12:00.650 --> 12:01.670 Should be what? 12:01.700 --> 12:02.780 36.4. 12:04.310 --> 12:05.420 Still, that is a challenge. 12:05.420 --> 12:09.590 How do I use two different public IPS for two different destinations? 12:11.390 --> 12:22.040 What they're going to do is based on where I'm going, I'm going to map the public address to it. 12:23.780 --> 12:27.050 I'm going to map the public address to a private address. 12:27.920 --> 12:33.260 I'm going to say, okay, listen, one dot to the address is 26.2. 12:34.280 --> 12:37.430 If you want to go to 1.3, the address is what? 12:40.140 --> 12:42.180 Otherwise the other one is 1.4. 12:42.180 --> 12:43.170 What is the address? 12:45.800 --> 12:48.800 And 1.5 is 36.. 12:50.660 --> 12:51.590 I'm going to map it. 12:52.430 --> 12:54.950 This is this this part is the private part. 12:56.360 --> 12:58.910 192.168.1. 12:59.900 --> 13:01.490 This is the private address range. 13:02.720 --> 13:04.100 The other part is the public. 13:06.420 --> 13:10.950 Based on what the destination remember always is based on destination. 13:12.270 --> 13:17.910 If privately the user wants to go to 192 168 1.3. 13:19.910 --> 13:22.550 The outside public address that will be used will be 36. 13:23.270 --> 13:29.750 If it wants to go to 1.4, the address will be 46.4 and so on and so forth based on something let's 13:29.750 --> 13:30.980 call it a table for now. 13:35.060 --> 13:35.870 Who resolves this? 13:35.870 --> 13:37.250 How do you have this table? 13:37.280 --> 13:40.480 We have a protocol which uses. 13:40.940 --> 13:41.630 It's known as. 13:45.140 --> 13:46.130 Next Hop resolution. 13:46.130 --> 13:46.640 Protocol. 13:48.710 --> 13:51.260 Next Hop resolution. 13:51.260 --> 13:51.920 Protocol. 13:52.460 --> 13:55.610 My next hop, which is 192 168 1.2. 13:55.610 --> 14:03.770 I need to resolve the public address of that your resolving the private addresses with the public address 14:04.400 --> 14:07.080 to understand where your tunnel destination is. 14:07.100 --> 14:13.100 So when you configure it, the first thing that you do, I leave these two things right? 14:13.340 --> 14:14.780 I said, Tunnel source. 14:15.440 --> 14:17.420 I said Interface Tunnel zero IP addresses. 14:17.420 --> 14:22.940 This tunnel source is 151 dot 16 dot one tunnel destination. 14:22.940 --> 14:26.030 I did not specify change the mode when you change the mode to mgr. 14:26.660 --> 14:29.270 Mgr does not work without the help of what? 14:32.770 --> 14:37.000 McGarry will not work unless you have np working with. 14:39.250 --> 14:42.790 We will help you to create that table with table private to public. 14:45.010 --> 14:45.430 Okay. 14:45.580 --> 14:46.960 How do you start that table? 14:49.670 --> 14:51.340 IP and network ID? 14:51.460 --> 14:52.720 Then you give a network ID. 14:53.380 --> 14:54.400 What is the network ID? 14:54.550 --> 14:58.150 Just like your IP has autonomous system numbers. 14:59.230 --> 15:02.890 You do router IP ten router IP 20. 15:02.920 --> 15:05.770 This is also a network ID is also just like that. 15:05.950 --> 15:10.180 You enable your process of by saying network ID is this. 15:12.650 --> 15:16.220 Again, there is a difference in the documentation and the way you apply it. 15:16.340 --> 15:19.550 Documentation says that it should be the same or not. 15:21.290 --> 15:24.040 For it to communicate to each other should be the same. 15:24.050 --> 15:27.710 But if you impose it and you keep different ones, it will still work. 15:30.020 --> 15:35.060 So if you want to follow, which we mostly would want to follow the documentation, you would keep it 15:35.060 --> 15:41.330 the same on all of us, on all of the spokes, like just like we would do any. 15:43.780 --> 15:45.520 What network? 15:45.790 --> 15:46.930 I'll say let's say ten. 15:47.380 --> 15:49.480 The moment you do this is on. 15:51.810 --> 15:52.950 Now you need to map. 15:54.840 --> 15:57.270 How do you map and map? 15:58.230 --> 15:59.280 What do you need to map? 15:59.280 --> 16:05.940 192 168 .1.2 is 151 dot 26 dot. 16:07.200 --> 16:08.340 Look at your diagrams. 16:08.850 --> 16:09.750 26 dot. 16:13.720 --> 16:16.990 I map 192 16:21.160 --> 16:27.490 1.3 is 151 dot 36 ..4 is. 16:38.230 --> 16:39.610 Your diary is complete now. 16:42.020 --> 16:46.130 Your diary will use a table called the table. 16:46.140 --> 16:46.310 So 16:49.130 --> 16:59.450 this is the table that your guy uses to go wherever he wants to based on the destination of where you're 16:59.450 --> 16:59.960 trying to go. 16:59.990 --> 17:01.550 One, 221681.2. 17:02.480 --> 17:06.500 It will choose the public address for that interface. 17:08.900 --> 17:10.880 Do you understand the concept of how it works? 17:10.890 --> 17:11.990 That's all I need to care. 17:12.000 --> 17:13.860 If you want me to repeat, I'll repeat any part. 17:13.860 --> 17:20.790 Again, this is your base of MVP, and if you understand this part, you understand how this works. 17:21.650 --> 17:21.800 How? 17:25.740 --> 17:26.250 Right now. 17:26.250 --> 17:26.820 Nothing. 17:27.390 --> 17:27.780 Right now. 17:27.780 --> 17:28.110 Nothing. 17:28.110 --> 17:31.050 You just maps to addresses together. 17:31.740 --> 17:32.820 It just maps. 17:33.210 --> 17:37.980 192 168, 1.221 50. 17:38.100 --> 17:40.740 It just maps it because you gave him the mapping, right? 17:41.250 --> 17:42.540 And it keeps it in a table. 17:43.050 --> 17:44.190 Doesn't know anything internally. 17:44.560 --> 17:45.690 Keeps this in a table. 17:46.380 --> 17:49.650 Then when you're now it has the whole table, right? 17:50.790 --> 17:55.350 Then when you're creating the header, the guy will come here, consult. 17:56.040 --> 17:56.310 Okay. 17:56.310 --> 18:00.060 If I want to go to the 1.2, I want to go to 26 dot. 18:01.290 --> 18:04.890 If I want to go to 1.3, I want to my outside header should be. 18:06.960 --> 18:07.380 36. 18:08.220 --> 18:09.420 Just consult the table. 18:12.210 --> 18:19.590 If you got doesn't cancar just sense it doesn't need to confirm whatever you enter here? 18:19.590 --> 18:20.850 It's static entries, right? 18:21.210 --> 18:22.340 This is a static entry. 18:22.350 --> 18:23.880 Whatever you enter, he'll accept it. 18:25.230 --> 18:25.530 Later. 18:25.530 --> 18:30.390 We'll see dynamic entries where he takes it by itself, but statically you can put it wrong. 18:30.390 --> 18:32.460 Also, in that case, your tunnel will not work. 18:34.680 --> 18:34.920 Right? 18:34.920 --> 18:40.320 It's like adding static entries to a mac address table if you put it wrong or even you put security. 18:40.320 --> 18:42.060 If you put the address wrong, it will not work. 18:42.330 --> 18:45.360 Similarly here you're statically creating the table. 18:46.320 --> 18:48.510 Then Dmvpn is consulting this table. 18:49.380 --> 18:51.180 Your is consulting the table. 18:52.910 --> 18:53.540 It is not. 18:56.270 --> 18:59.640 We need to create the table on all the is good good consideration. 18:59.640 --> 19:00.060 Right. 19:00.390 --> 19:03.800 We need to do it on all the routers, obviously. 19:04.620 --> 19:05.410 How was it scaled? 19:06.790 --> 19:09.490 So that's again, very good. 19:09.850 --> 19:11.140 It's not still scalable. 19:12.430 --> 19:13.120 It still is not. 19:13.120 --> 19:15.730 So we'll have to do something else for scalability. 19:16.180 --> 19:16.450 Right? 19:18.960 --> 19:24.510 INT channel zero IP address 1921681.1 19:27.040 --> 19:28.390 write tunnel. 19:29.130 --> 19:31.290 Source is what? 19:32.280 --> 19:32.610 12. 19:33.090 --> 19:34.320 16.1. 19:35.580 --> 19:40.470 Tunnel destination is not there anymore, so we change it by tunnel mode. 19:41.680 --> 19:41.780 Are. 19:45.370 --> 19:48.490 Since you are not specifying the tunnel destination, what do you do? 19:49.270 --> 19:55.930 IP and IP and network ID say ten. 19:56.080 --> 20:02.980 Then you start mapping IP and map if you want to go to 192 168 1.2. 20:03.910 --> 20:07.330 The next stop is your outside address is $26. 20:14.890 --> 20:17.500 This is 36.34. 20:17.530 --> 20:20.750 Is 36.45. 20:20.770 --> 20:21.250 Is 20:24.880 --> 20:25.750 56 point. 20:28.450 --> 20:28.690 Right. 20:29.020 --> 20:29.800 That's it. 20:30.490 --> 20:31.270 You're done. 20:31.720 --> 20:33.190 Let's move to the other side. 20:34.810 --> 20:37.630 This is our one. 20:39.040 --> 20:39.850 Let's move to our two. 20:42.100 --> 20:43.930 The best part is you could copy paste. 20:46.940 --> 20:54.710 The address is going to be, what, 192 168 1.242. 20:55.490 --> 20:56.920 What is the transpose? 20:59.780 --> 21:02.690 If r two wants to go to 192 168 1.1. 21:02.720 --> 21:04.760 His next stop is 16. 21:05.030 --> 21:06.230 Everything else is the same. 21:06.860 --> 21:07.430 It wants to go to. 21:07.430 --> 21:11.120 Three is public address is 30 6.3. 21:11.510 --> 21:12.830 Four is 46.4. 21:12.830 --> 21:13.970 Five is 56. 21:15.820 --> 21:16.210 Copy it. 21:18.370 --> 21:19.930 Go to A2 and paste it. 21:22.150 --> 21:23.350 Do you think this will work? 21:26.240 --> 21:27.890 1816281.1. 21:32.820 --> 21:33.240 Should work. 21:36.050 --> 21:37.340 Want to have a look at the packet. 21:40.780 --> 21:41.110 Jan. 22:01.110 --> 22:06.810 Axle packet going from 192 and 68, 1.2 to 192 1681.1. 22:07.080 --> 22:10.860 The outside header is resolved to 151 dot 16 dot one. 22:11.280 --> 22:13.180 Source will always remain the same. 22:13.200 --> 22:16.350 Your job is always this part is always. 22:16.350 --> 22:21.450 Remember NP works here and here. 22:23.370 --> 22:28.080 Based on the internal destination, it will give you the external destination based on the inner header. 22:28.080 --> 22:32.520 It will give you the outer header depending upon where you're trying to go. 22:35.430 --> 22:38.340 It's trying to go to 1.1, so the destination will change to 16. 22:40.130 --> 22:40.570 Right. 22:40.740 --> 22:42.660 Let's paste this on all of the others. 22:55.600 --> 22:57.040 This will be 26.2. 23:04.760 --> 23:05.240 Why not? 23:08.190 --> 23:08.450 Yeah. 23:15.030 --> 23:15.840 1.2. 23:23.540 --> 23:24.230 The check. 23:24.350 --> 23:30.680 181681.1 I can communicate 1.2 also I should be able to okay also. 23:38.830 --> 23:42.520 This is for 46.4. 23:48.160 --> 23:49.480 Three will be 36 dot. 23:57.940 --> 23:58.960 These are five quickly. 24:14.110 --> 24:14.350 That. 24:19.460 --> 24:19.700 Then. 24:22.350 --> 24:23.700 Just try and see if it works. 24:31.240 --> 24:31.720 Multiple. 24:34.060 --> 24:35.800 This is a multi point tunnel. 24:36.370 --> 24:38.560 Everybody is using the same IP address. 24:40.390 --> 24:42.360 Everybody is using the same IP address. 24:42.390 --> 24:43.110 Subnet. 24:43.110 --> 24:44.340 Subnet is the same. 24:44.520 --> 24:50.840 Endpoint hosts are different, but it is a multi point group. 24:54.930 --> 24:55.200 Right. 24:57.000 --> 24:58.770 Any more questions in here? 25:02.430 --> 25:05.280 The have we solved the problem of having multiple tunnels? 25:05.280 --> 25:05.970 Yes. 25:06.000 --> 25:09.060 So now we don't have to create separate tunnels for each of them. 25:09.060 --> 25:12.570 We can just have one big tunnel and solve everything with mappings. 25:13.020 --> 25:18.990 But the problem of scalability, it is scalable as compared to the old one. 25:18.990 --> 25:24.180 So if the other one could support 3 to 4 tunnels, nice, this one can support more. 25:25.170 --> 25:28.920 The only issue is if you add more what happens? 25:30.180 --> 25:31.170 I have five right now. 25:31.170 --> 25:32.310 I'll add a sixth one. 25:32.550 --> 25:37.890 If I add a sixth one which are seven to the topology. 25:41.510 --> 25:42.550 What am I doing? 25:42.560 --> 25:46.400 This is 67.0. 25:48.140 --> 25:49.970 I need to resolve it on all the routers. 25:49.970 --> 25:50.560 First. 25:50.570 --> 25:51.620 I need to tell R1. 25:51.620 --> 25:59.240 Listen, if you want to go 2.7, your address is 67.7 R2, R3, r4, r5. 25:59.240 --> 26:06.680 I need to tell everybody then r7, I need to make another one, two, three, four five statements. 26:09.360 --> 26:10.710 Five more statements. 26:11.340 --> 26:13.110 The question is not yes, it's fine. 26:13.110 --> 26:15.990 It's easier than before, but I'll add another one. 26:15.990 --> 26:17.850 So I'll have to add six more statements. 26:18.240 --> 26:19.050 I'll add another one. 26:19.050 --> 26:21.890 Seven more statements, 1000 tomorrow. 26:21.900 --> 26:27.540 If I have 1000 strokes, I'll have to have 1000 different mappings on that scope. 26:29.400 --> 26:35.850 And imagine the added load of adding each one line of that command to all of the other 999 scopes. 26:36.180 --> 26:37.290 Quite difficult to do. 26:37.980 --> 26:39.090 Not scalable. 26:39.090 --> 26:40.080 Still not scalable. 26:42.450 --> 26:42.690 Scale. 26:42.690 --> 26:43.680 Not stable. 26:43.710 --> 26:44.730 Do you understand why? 26:45.810 --> 26:48.090 Why is it not scalable at the back? 26:50.310 --> 26:52.020 Do you understand why it's not scalable? 26:54.420 --> 26:54.680 Right. 26:54.840 --> 26:56.400 How do I prevent this? 26:56.640 --> 26:57.660 What do I do? 26:59.700 --> 27:02.310 First of all, I'll clear all of this. 27:08.990 --> 27:10.260 I get all the mappings. 27:20.540 --> 27:21.080 Is better. 27:21.080 --> 27:21.920 Just. 27:28.400 --> 27:29.360 Remove this whole thing. 28:00.070 --> 28:00.610 Dot three. 28:26.350 --> 28:26.550 Then. 28:27.360 --> 28:28.830 Now they won't be able to communicate. 28:29.190 --> 28:31.890 I've removed what my maps. 28:32.760 --> 28:37.500 But remember these mappings, what we did with these mappings, the whole concept behind what we are 28:37.500 --> 28:38.250 trying to do. 28:44.210 --> 28:44.630 Okay. 28:45.410 --> 28:49.220 The next thing that I want to do is we want to do all of this dynamically. 28:51.020 --> 28:52.640 Everything should be dynamic. 28:53.520 --> 29:03.970 How we have a concept by provided again by our one and only NP is known as NS. 29:04.880 --> 29:06.620 Next hop server. 29:07.520 --> 29:15.620 What I could do is I could have this guy R1 act as a next hop. 29:19.470 --> 29:19.890 Next up. 29:19.890 --> 29:22.470 So what does that mean? 29:23.190 --> 29:26.190 That means all the users. 29:27.210 --> 29:28.620 All the other guys. 29:28.980 --> 29:31.650 First of all, I'll have to go to them and point them to the server. 29:32.190 --> 29:42.240 So what they will do is the moment I start on them, they will create a packet in which they mention 29:42.660 --> 29:46.440 that my inside address is 192. 29:46.470 --> 29:48.750 168 .1.3. 29:49.320 --> 29:50.970 My outside address is. 29:57.090 --> 29:57.360 Today. 29:58.080 --> 30:03.390 It's known as Nrhp resolution registration. 30:07.920 --> 30:09.150 Registration request. 30:12.280 --> 30:17.050 The same information that you use to enter here manually on the server. 30:18.910 --> 30:23.920 The same information that you use to enter will be given by R3 dynamically to R1. 30:27.670 --> 30:37.650 You know, the moment you enable all the connections, all these connected devices. 30:37.650 --> 30:44.130 So our phone will take his mapping, R5 will take his mapping, R2 will take his mapping Register with 30:44.130 --> 30:44.550 whom? 30:46.860 --> 30:48.440 I do not know. 30:48.930 --> 30:49.380 Uniqua. 30:51.690 --> 30:52.160 Uniqua. 30:52.530 --> 30:53.340 I'll explain how. 30:54.900 --> 31:00.390 I'll explain how the shark is running so we can see those registration requests. 31:00.470 --> 31:05.340 All right, then. 31:06.510 --> 31:11.670 Once everyone has all the mappings, R-1 should be able to communicate to R3. 31:11.700 --> 31:12.960 R2, R5 and R4. 31:12.960 --> 31:13.410 Right. 31:14.700 --> 31:18.280 Let's see how on the NHS. 31:18.300 --> 31:22.710 You don't need to configure anything because people will come and register to them. 31:23.220 --> 31:25.310 Before I do that, let me show you the mappings. 31:25.320 --> 31:26.550 Did I show you the mappings on R1? 31:26.550 --> 31:26.910 I think. 31:29.360 --> 31:31.280 These mappings until now were a wish type. 31:32.690 --> 31:33.670 Static mappings, right. 31:33.680 --> 31:35.020 Because you entered them in the table. 31:35.030 --> 31:38.090 Right now, if you check the table again, you'll see that it's empty. 31:39.500 --> 31:40.000 So. 31:40.970 --> 31:43.250 So it's empty. 31:44.060 --> 31:45.530 The table is still empty. 31:46.100 --> 31:48.890 On this side we call R1 the Hub. 31:49.850 --> 31:52.010 The server is also known as the hub. 31:52.010 --> 31:52.790 On the hub side. 31:52.790 --> 31:54.440 I don't need to configure anything. 31:54.560 --> 31:57.920 I'll go to R2 in the interface Channel zero. 31:59.390 --> 32:00.350 I'll first map it. 32:00.350 --> 32:08.360 I'll say map 192 168 .1.1 is 151 dot 16 dot. 32:09.350 --> 32:10.370 Why do I need to map? 32:11.090 --> 32:18.080 Because when he goes registers he should know the public address of where is he going to register and 32:18.080 --> 32:19.040 then I'll give him the NHS. 32:19.160 --> 32:26.030 I'll say if NHS is remember this is a private address, don't make a mistake here. 32:29.230 --> 32:30.160 Two things I tell him. 32:31.810 --> 32:32.470 I tell him where? 32:32.470 --> 32:34.630 192 168, 1.1 is. 32:35.380 --> 32:37.810 And then I tell him, okay, let me do this. 32:41.310 --> 32:42.780 This is a much easier way of doing it. 32:42.810 --> 32:43.710 Wipe it out. 32:44.250 --> 32:49.620 What I do is I tell them NHS is 192 168 .1.1. 32:49.620 --> 32:50.250 Which is correct. 32:50.250 --> 32:50.550 Is it? 32:50.970 --> 32:52.010 That is my NHS. 32:52.020 --> 32:52.470 Right. 32:52.560 --> 32:55.200 But since this is a private address I need to map it 32:59.430 --> 33:00.690 because he doesn't know where it is. 33:00.690 --> 33:01.140 Right. 33:03.800 --> 33:11.310 I map 192 168 1.1 and it tells him that that guy is 16 dot. 33:13.440 --> 33:23.730 It goes unicast to 16.1 because when he creates the packet of registration, the packet will go from 33:23.940 --> 33:30.420 190 to 168, 1.2 to 2 1.1. 33:31.440 --> 33:33.000 Then he needs to attach 33:35.520 --> 33:43.980 outside of tunnel source will be 26 dot to destination based on 192 168 1.1. 33:43.980 --> 33:46.830 He will choose it as because you have given him a static mapping. 33:47.130 --> 33:50.490 You choose the destination as what 16 dot? 33:54.010 --> 33:58.090 This is the n r p registration. 33:59.490 --> 33:59.910 It's. 34:02.560 --> 34:02.920 Okay. 34:03.520 --> 34:07.090 You can have a look at it this time. 34:09.980 --> 34:10.340 Yeah. 34:11.090 --> 34:16.040 Only the servers across the NHS, which you specify that guy's address has to be written on the spokes 34:16.040 --> 34:20.210 has to be statically entered on the spokes because that's how they'll go and register themselves. 34:22.610 --> 34:23.810 You want to see the registration? 34:33.220 --> 34:40.260 Registration request and registration code is success on the server. 34:40.570 --> 34:42.400 Server reply is saying a successfully. 34:42.400 --> 34:44.290 I've added your registration. 34:44.560 --> 34:46.840 Whatever you told me to register, I've added it. 34:47.080 --> 34:48.650 And what has he added? 34:48.670 --> 35:00.610 If you go to the server and you do a show IP and a dynamic entry either and enter it for 192 168 1.2 35:02.140 --> 35:05.290 The NVM address the public address is what? 35:05.740 --> 35:06.970 26.3. 35:07.930 --> 35:10.570 Have a look at the table and see if you understand. 35:13.360 --> 35:14.530 It will continue. 35:15.640 --> 35:16.120 Nothing. 35:16.960 --> 35:19.330 Again by default. 35:19.330 --> 35:24.220 The guy came who came when I 168 1.2 with his private address and his public address. 35:24.640 --> 35:26.620 And he says, okay, I want to register myself. 35:28.480 --> 35:33.790 La la la la follette's By default, what is AI enabled? 35:34.600 --> 35:36.290 IP Network ten. 35:39.130 --> 35:40.840 Network ten is on. 35:44.650 --> 35:55.150 You need to is just like I said, autonomous system number, just like in network enables, it enables 35:55.150 --> 35:56.320 the whole process of nature. 35:57.130 --> 35:59.560 So you you need that, right? 35:59.590 --> 36:01.510 If you want to have a look at what I did here. 36:04.570 --> 36:05.500 These are my configs. 36:06.460 --> 36:07.030 This is my hub. 36:08.170 --> 36:08.920 R1 is the hub. 36:09.820 --> 36:10.660 That's all I did here. 36:10.660 --> 36:11.550 I did not resolve. 36:11.560 --> 36:12.490 I only have the source. 36:12.490 --> 36:14.710 I don't resolve anything about the destination. 36:15.220 --> 36:18.340 I go to R2, I say IP and IP network ID is ten. 36:19.420 --> 36:22.540 Then I say, okay, go and register yourself. 36:22.540 --> 36:23.020 To whom? 36:24.880 --> 36:28.360 192 160 81.. 36:28.780 --> 36:32.310 Since he doesn't know where that guy is, I need to tell him where that guy is. 36:32.320 --> 36:35.500 IP and map. 36:40.750 --> 36:41.440 151. 36:41.470 --> 36:46.360 Not the moment I do this, it knows where to go. 36:46.400 --> 36:48.130 Goes there and registers itself. 36:52.170 --> 36:52.440 What? 36:55.810 --> 36:56.340 Good night. 36:58.080 --> 36:59.340 The decision complete. 36:59.370 --> 37:00.390 Let's do the same thing. 37:00.390 --> 37:00.610 Where? 37:00.660 --> 37:01.380 On the others. 37:02.490 --> 37:03.180 Copy this. 37:04.260 --> 37:05.580 I need to tell them the same thing. 37:05.580 --> 37:06.020 Right. 37:06.030 --> 37:09.300 I need to tell them your NHS is 182 and 68 1.1. 37:09.390 --> 37:13.080 I need to tell them their next stop is 16.1, which is correct for all of them. 37:13.080 --> 37:14.040 Always. 37:17.240 --> 37:19.400 Do you understand at the back what I'm doing? 37:21.130 --> 37:27.120 Stuff that goes down, then we'll have dual hub Hub dungeons can have more than one hubs. 37:29.320 --> 37:30.290 I do is done. 37:30.890 --> 37:35.870 I'll go to 3 or 4. 37:38.250 --> 37:38.910 And I think. 37:46.910 --> 37:47.300 Okay. 37:47.630 --> 37:50.000 The moment I do this, if you check your Wireshark 37:52.790 --> 37:57.650 registration request from R3, request from R4 request from our 38:01.810 --> 38:02.500 is a serial link. 38:02.590 --> 38:04.710 I have connected serial links. 38:04.730 --> 38:05.000 Right. 38:09.170 --> 38:09.740 Is this clear? 38:12.580 --> 38:14.710 Registration request and registration replies. 38:15.130 --> 38:16.380 They've all gone and registered. 38:16.390 --> 38:17.440 I just copied paste. 38:17.590 --> 38:22.920 Copied and pasted the same command and is going to be 1.1. 38:22.930 --> 38:25.440 And for you to reach there. 38:25.450 --> 38:26.140 This is the address. 38:26.150 --> 38:28.240 This is the public address for you to reach the NHS. 38:28.570 --> 38:31.990 So it goes and registers to the NHS if you see our one right now. 38:36.820 --> 38:39.430 Two, three, four, five have come and registered to me. 38:40.540 --> 38:43.900 This entry stays in the table for two hours. 38:46.950 --> 38:50.880 This dynamic entry stays in the table for two hours. 38:50.910 --> 38:54.420 After two hours, the hubs will the spokes will come and register themselves again. 38:58.640 --> 38:59.000 Okay. 38:59.810 --> 39:01.610 Until then, it will stay in that table. 39:06.130 --> 39:06.390 Okay. 39:10.570 --> 39:16.600 You can do that on taxes on right now by default, there's nothing by default. 39:16.630 --> 39:20.320 No, but usually what you would do is you would run on it. 39:22.220 --> 39:23.050 It doesn't work. 39:23.050 --> 39:27.540 You don't use a mjnari or a VPN without the. 39:27.940 --> 39:29.650 Hazards package that works as. 39:33.510 --> 39:34.560 Any questions? 39:38.600 --> 39:40.220 Any part you want me to repeat? 39:43.150 --> 39:44.230 Is this clear what I did? 39:48.140 --> 39:49.520 That's not true. 39:54.900 --> 39:56.140 So looks like. 39:57.280 --> 40:00.920 Yes, Yes, it has to. 40:00.930 --> 40:03.060 Basically, I'm telling him, this is your server. 40:03.090 --> 40:04.500 You have to go register to him. 40:04.500 --> 40:05.010 That's it. 40:05.280 --> 40:11.250 Go to him and tell him what your private and public address is, because it is directly connected to 40:12.540 --> 40:14.070 how this book is advertising. 40:15.540 --> 40:15.790 How? 40:19.540 --> 40:21.820 People are coming to him and registering themselves. 40:21.970 --> 40:22.600 He doesn't care. 40:22.720 --> 40:29.320 Hundreds of people can come just because the registration request comes. 40:30.100 --> 40:31.600 When he gets a request, he accepts it. 40:32.230 --> 40:33.820 When he gets another request, he accepts it. 40:33.850 --> 40:35.440 When he gets another request, he accepts it. 40:35.650 --> 40:38.680 Right now, the question is, can you send a request to other ones? 40:38.680 --> 40:39.730 Can you register with them? 40:39.730 --> 40:40.390 You can. 40:41.560 --> 40:45.830 If I go to R3 and I give him an R5, we will go and register itself with R5. 40:45.850 --> 40:46.540 Not a problem. 40:47.030 --> 40:50.200 That is what you do for redundancy. 40:50.200 --> 40:52.110 That's how we'll do for redundancy. 40:52.120 --> 40:53.290 But that's later. 40:53.620 --> 40:54.130 Yeah. 40:56.380 --> 41:00.970 If you want to make a design flaw, you would do that, but you wouldn't want to do that. 41:01.060 --> 41:02.170 It's possible. 41:02.530 --> 41:09.340 It's I mean, you can do that, but we will use it in dual hubs when we have two hubs for redundancy. 41:09.670 --> 41:13.690 So one guy will go and register to two people, so one dies, the other one will take over. 41:15.100 --> 41:15.370 Yeah. 41:15.410 --> 41:21.380 How is it a design flaw if you are having you're registering for two people, right? 41:21.380 --> 41:23.810 But then you have to do all the everything here. 41:24.770 --> 41:25.550 It still would work. 41:26.270 --> 41:27.050 What would work? 41:28.640 --> 41:31.100 Let's say you have the exchange would happen. 41:31.250 --> 41:35.060 R5 but later you have a lot of things that you have to do on the hub side. 41:35.630 --> 41:36.770 It's not only this. 41:36.800 --> 41:37.520 You have to run. 41:38.240 --> 41:39.650 You have to run a lot of other things. 41:39.650 --> 41:44.870 So you might design flaw is if you do it on a spoke, if you're pointing it to a spoke, not talking 41:44.870 --> 41:45.470 about the hub. 41:47.540 --> 41:48.830 R5 is a spoke, right? 41:50.000 --> 41:53.030 But when you pointed to a spoke, it automatically becomes a hub. 41:53.630 --> 41:54.950 It will go and register itself. 41:54.980 --> 41:57.440 Yes, R3 will go a register itself with R5. 41:57.680 --> 41:59.780 But again, there's other things that you have to do. 41:59.810 --> 42:01.100 Right now it's not complete. 42:01.610 --> 42:02.870 Right now, nothing is complete. 42:02.870 --> 42:04.730 If you see right now, it's an incomplete. 42:05.060 --> 42:09.710 We have moved from was mappings, only mappings. 42:09.740 --> 42:15.200 Now we are moving to something bigger than that, but it's not complete yet. 42:16.190 --> 42:18.800 It will be complete When what? 42:22.560 --> 42:27.630 When the networks behind will communicate, that is when it will be complete. 42:28.660 --> 42:30.560 So then you can just normally run. 42:31.900 --> 42:36.690 When it is not a normal working, that that's the whole thing about DMV team. 42:37.770 --> 42:42.780 That's why they've included this in your Ccnp routing instruction. 42:44.520 --> 42:52.200 Use the you see any difference between this and the one which you ran before in your tunnels? 42:55.580 --> 42:56.360 There is a difference. 42:56.360 --> 42:59.810 There is a huge difference in the routing protocol that you're going to run. 42:59.810 --> 43:00.640 We'll see that. 43:00.650 --> 43:04.310 But before that, tell me right now, can R1 communicate to everybody? 43:06.650 --> 43:12.230 R1 has the mappings, all of them have the mappings towards R1, so they should be able to communicate, 43:12.230 --> 43:12.410 right? 43:12.410 --> 43:14.060 So if R1 goes and pings 43:16.100 --> 43:22.010 1.21.31.4 and one dot no configuration needed on R1. 43:22.700 --> 43:29.570 So run interface tunnel zero if you see he doesn't have even have the destination mapped, where does 43:29.570 --> 43:30.800 he get all his mappings from? 43:30.800 --> 43:32.000 From the table. 43:35.520 --> 43:36.620 From the end of 43:40.210 --> 43:43.020 in one and in fact. 43:44.110 --> 43:45.710 Know, network 190 to 1. 43:49.290 --> 43:51.840 You know, you have to tweak it. 43:52.920 --> 43:53.460 We'll do that. 43:53.460 --> 43:54.900 That's that's what we're doing today. 43:55.710 --> 43:58.260 That would be the last thing that we have to do before that. 43:58.260 --> 44:01.380 There's another problem I want to talk to. 44:01.380 --> 44:03.240 I want all of them only to talk to R1. 44:03.240 --> 44:05.040 I want them to talk to each other also. 44:05.160 --> 44:06.240 That was the whole point. 44:07.380 --> 44:12.300 What is the point of if I go to all of them and give them the mapping towards R1 and they start talking 44:12.330 --> 44:12.930 to R1? 44:12.930 --> 44:13.770 That's not the point. 44:13.770 --> 44:17.670 I want R2 to talk to R3 for this. 44:17.700 --> 44:18.000 Now. 44:18.000 --> 44:24.600 This process is a little tricky, so keep your concentration and try to understand what I'm trying to 44:24.600 --> 44:24.810 say. 44:27.000 --> 44:32.460 I'll show you not basically just say what I'll do is I'll ping from R2 to R3. 44:33.810 --> 44:44.610 Do you think it will go to R3 to how how the mapping information? 44:45.830 --> 44:55.200 See, when I create the packet for going from 180 to 168 .1.1 and I want to go where 44:57.660 --> 45:01.740 1.2 I want to go to 1.2. 45:02.670 --> 45:03.140 Right. 45:03.840 --> 45:04.830 Header will be added. 45:06.360 --> 45:07.470 Sorry, not 1.1. 45:08.220 --> 45:09.450 Let's say from 1.3. 45:13.860 --> 45:15.060 Jerry header is added. 45:15.300 --> 45:16.500 Source is what? 45:16.770 --> 45:17.800 26.2. 45:17.820 --> 45:19.080 What destination do I use? 45:23.770 --> 45:27.640 When I was going to 1.1, I have the destination in my mappings. 45:28.390 --> 45:31.120 When I go to 1.2, what destination address do I use? 45:32.470 --> 45:41.620 This piece server server would not send, but I can request Stone as a resolution request. 45:43.480 --> 45:50.160 I can send a request to the server and resolution request asking for the public address of whom? 45:50.230 --> 45:51.640 192 168 one. 45:51.640 --> 45:55.030 Not a separate request will be sent. 45:55.510 --> 45:56.860 The request. 45:57.130 --> 45:57.880 Who is? 46:03.840 --> 46:05.250 192 168 1.2. 46:05.280 --> 46:07.260 This request will be sent. 46:07.260 --> 46:07.890 To whom? 46:08.790 --> 46:10.380 Now see the process. 46:10.560 --> 46:11.940 Check the process out. 46:12.630 --> 46:13.620 This is the trick. 46:14.100 --> 46:24.780 The request goes from R2 to hub checks his mappings in the mappings it finds out 192 168. 46:24.810 --> 46:30.630 1.2 is 36 .31. is not looking for two is looking for dot. 46:35.050 --> 46:39.100 Ivan figures out that the address is, what, 36.3? 46:39.400 --> 46:42.900 It does not just reply and tell him it's 36.3. 46:42.910 --> 46:43.240 No. 46:44.110 --> 46:49.110 It forwards this request to 191 51 dot 30 6.3. 46:51.820 --> 46:59.440 Creates a new request, doesn't just forward, it creates a new request meant for 36.3 telling 36.3. 46:59.470 --> 47:06.310 Hey listen, please reply to 153.1. 20 6.2. 47:06.340 --> 47:10.810 Please reply to this guy and tell him what your address is. 47:11.800 --> 47:14.440 The reply goes from R3 straight to. 47:18.440 --> 47:20.270 Pointing in the wrong directions. 47:20.960 --> 47:21.740 Say to whom? 47:22.640 --> 47:22.790 I. 47:26.860 --> 47:27.790 Request. 47:28.150 --> 47:29.860 Request reply. 47:31.090 --> 47:32.230 This is the request. 47:33.250 --> 47:34.390 This is the request. 47:34.720 --> 47:35.770 And this is the. 47:42.350 --> 47:42.950 This is the reply. 47:44.930 --> 47:50.690 The reply should always come from the actual batch, the actual destination. 47:51.230 --> 47:52.820 Then only he will accept it. 47:53.120 --> 47:54.680 If R1 had replied. 47:54.710 --> 48:01.520 R1 would have replied with its own public address in the destination part of his resolution reply that 48:01.520 --> 48:03.860 would not have been acceptable to R2. 48:05.090 --> 48:09.440 R2 should get a reply in which the destination, the source of that packet should be the public address 48:09.440 --> 48:11.420 which is going to take care. 48:11.420 --> 48:15.650 The source is going to be 26 dot 30 6.3. 48:15.650 --> 48:20.750 So when he receives the reply he will get the reply as 36 dot. 48:23.790 --> 48:25.380 Remember again one more time. 48:26.220 --> 48:27.900 R2 wants to communicate to R3. 48:28.650 --> 48:31.980 He wants to go from one dot 2 to 1 dot. 48:34.340 --> 48:38.270 And they'd be doing 68 1.221 92 1681.3. 48:38.390 --> 48:42.650 It doesn't know where 1.3 is, so it goes to the server, asks for 1.3. 48:43.130 --> 48:45.620 The server looks at 1.3 checks. 48:45.620 --> 48:47.450 1.3 is 36.3. 48:47.930 --> 48:51.320 Sends out a request to 36.3 tells it. 48:51.440 --> 48:52.310 Listen. 48:52.940 --> 48:54.980 26.2 is looking for you. 48:57.350 --> 48:59.060 26.2 is looking for you. 48:59.180 --> 49:02.240 Please reply to him with your private address. 49:02.240 --> 49:13.250 So he creates a packet saying I am 192 168 .1.3 but in this packet it will also have a source and destination. 49:13.250 --> 49:13.730 Right? 49:13.970 --> 49:16.670 The source will be 36.3. 49:16.670 --> 49:24.920 Destination will be this packet will reach what 26 dot 26 or 2. 49:24.920 --> 49:28.250 Will take what this part and put it in his map. 49:31.360 --> 49:33.060 I won't tell them. 49:34.800 --> 49:36.570 Public IP gives them the public IP. 49:36.600 --> 49:38.710 He doesn't go to 192 1681.2. 49:38.730 --> 49:40.400 No, it does. 49:40.440 --> 49:43.260 It's not sending the packet to 192 168 1.2. 49:43.530 --> 49:45.060 This is an IP packet. 49:47.830 --> 49:48.590 It's not tunneled. 49:50.610 --> 49:51.080 Phase one. 49:51.090 --> 49:52.440 We haven't even moved to phase one. 49:52.440 --> 49:53.760 This is not even a VPN 49:56.970 --> 49:59.870 and it's only in here and here. 50:00.060 --> 50:09.180 This is actually replying to the public IP, the public IP of 26.2 and it's specified to R3 by R1 and 50:09.180 --> 50:15.480 it's coming from a source of 192181. no from the public IP. 50:18.020 --> 50:18.440 Yeah. 50:18.470 --> 50:18.920 What? 50:23.100 --> 50:31.590 Question, then ask if you have any confusion, just ask. 50:31.950 --> 50:33.660 I know this is a little tricky. 50:34.320 --> 50:35.580 There is a little trick in there. 50:35.580 --> 50:37.050 That's why I said it in the beginning. 50:37.740 --> 50:39.720 As much as time as this is going to take. 50:39.750 --> 50:43.350 We are not going to move on to finish this unless you understand this. 50:44.130 --> 50:51.750 When actually replies that 2 or 3 replies back to our two, it doesn't reply back to our two, it doesn't 50:51.750 --> 50:52.890 reply back to our two. 50:53.850 --> 50:55.590 R2 never sent a packet to R3. 50:57.190 --> 51:00.240 R1 sends a packet to R3 in that packet. 51:00.390 --> 51:01.920 It says reply to R2. 51:02.040 --> 51:03.360 The public address of R2. 51:05.250 --> 51:09.200 First it goes to remember before going anywhere. 51:09.210 --> 51:13.710 These are packets, these are not tunnel packets, these are not going through the tunnel. 51:16.260 --> 51:18.330 Packets go from public address to public address. 51:18.330 --> 51:18.870 That's it. 51:20.330 --> 51:21.150 They're not tunnel. 51:21.150 --> 51:25.630 They're not going from 192, 168, 1.1 to 1.2 or to 1.2 to 1.3. 51:25.630 --> 51:29.260 No, they are public to public addresses. 51:29.860 --> 51:31.150 How do they know the public addresses? 51:31.150 --> 51:32.320 You've already specified them. 51:32.420 --> 51:38.860 So resolution request, because it knows that the public address for the resolution is 16.1. 51:38.860 --> 51:46.630 So he goes to 16.1, then R1 figures out the public address of 1.3, forwards the packet to 1.3. 51:46.630 --> 51:48.490 But in this packet, what does he say? 51:49.420 --> 51:53.800 Reply to 26.2. 51:56.960 --> 51:58.850 Reply to the public address of 26. 51:59.270 --> 52:07.160 So the packet is created like this coming from 36.3 to 26.2 saying I am 52:09.170 --> 52:10.820 168.1.. 52:13.540 --> 52:17.410 Since the public address is 26.2, the source is 36.3. 52:17.590 --> 52:18.910 It moves and goes to. 52:23.030 --> 52:26.120 The song concept will keep on repeating from now until phase three. 52:26.240 --> 52:28.670 Yes, the first bracket is in the pilot. 52:29.780 --> 52:30.470 Which one? 52:30.500 --> 52:32.150 No, this is not. 52:32.330 --> 52:32.690 Not. 52:32.690 --> 52:33.790 Not from private IP. 52:33.800 --> 52:37.910 Still, when you think 192131.3. 52:38.750 --> 52:39.630 Would be a private. 52:40.510 --> 52:42.740 I mean, the ping is kept on hold. 52:44.960 --> 52:49.130 When you ping the first time, the ping will be kept on hold because it would not know where. 52:49.130 --> 52:50.060 1.3 is. 52:50.270 --> 52:56.780 A separate resolution request will go out, resolve itself, and then come back in again. 52:57.810 --> 53:03.350 And once I have that and I do the thing again, it still would be from the private then. 53:03.530 --> 53:09.020 Then once it gets the reply right in his table, it will have the resolution. 53:11.290 --> 53:14.420 Next up is and whatever I do. 53:15.460 --> 53:18.220 After that, it will go directly to that. 53:19.780 --> 53:20.770 After that, it will go down. 53:22.360 --> 53:24.280 Yes, obviously, that's the whole point. 53:24.520 --> 53:29.110 The question is this is not going to be one way because ping is a request and echo reply. 53:29.230 --> 53:33.700 So this guy also needs to reply when he needs to reply. 53:33.730 --> 53:37.990 It would also send a resolution request because it needs to know which address. 53:38.380 --> 53:39.400 1.2. 53:43.780 --> 53:46.300 It needs to deploy from 190 to 168. 53:48.780 --> 53:50.130 1.32. 53:50.280 --> 53:51.180 The reply. 53:54.920 --> 53:55.610 For that reply. 53:55.610 --> 53:59.920 It needs to do the mapping of for that mapping. 53:59.930 --> 54:00.710 What does it do? 54:01.280 --> 54:02.060 Request. 54:04.120 --> 54:04.840 Request. 54:08.400 --> 54:09.810 And I will reply directly. 54:13.700 --> 54:14.720 In total. 54:14.750 --> 54:17.630 How many requests are you going to see on this interface? 54:20.230 --> 54:21.310 One, two, three, four. 54:22.090 --> 54:26.890 One, two, three, four. 54:29.790 --> 54:32.640 How many replies on this interface? 54:34.960 --> 54:36.070 On this interface. 54:36.790 --> 54:37.480 One reply. 54:37.510 --> 54:38.080 This direction. 54:38.080 --> 54:40.660 One reply, one reply. 54:40.700 --> 54:42.190 R3 will be replying to R2. 54:42.220 --> 54:48.610 The other one R2 will be replying to Y to two cycles will be here. 54:48.610 --> 54:48.840 Right? 54:48.850 --> 54:50.170 R2 will be sending a packet. 54:50.170 --> 54:51.820 So his resolution will be like that. 54:53.110 --> 54:57.160 When our three has to reply, his resolution will be like that. 54:58.270 --> 55:00.550 But R3 already has information. 55:01.630 --> 55:02.440 No, it doesn't. 55:03.000 --> 55:05.410 Doesn't have it doesn't. 55:05.410 --> 55:08.080 It's just replying to a resolution request. 55:08.110 --> 55:09.880 It has not sent his own request. 55:13.060 --> 55:14.920 You need to send out a request to resolve. 55:17.230 --> 55:20.800 I think that you didn't have information on how to listen to offers. 55:21.370 --> 55:24.360 It doesn't have the information for what I like. 55:26.200 --> 55:28.240 It sends the reply back to you, right? 55:28.480 --> 55:32.620 Yes, it does have the information, but not the private address. 55:32.980 --> 55:37.390 It doesn't know which private address is it replying to is only public to public. 55:38.290 --> 55:40.420 There is no private communication. 55:40.630 --> 55:42.310 These are control plane traffics. 55:42.310 --> 55:44.020 These are all going public to public. 55:44.500 --> 55:45.520 These are not tunnels. 55:47.170 --> 55:49.600 All your traffic is going public to public. 55:51.310 --> 55:53.170 Okay, let's have a recap again. 55:55.660 --> 55:57.570 He actually wants to come to Parliament. 55:58.090 --> 56:00.160 Let's say R2 wants to bring R3. 56:01.130 --> 56:03.340 A reply will also be generated, right? 56:03.370 --> 56:08.260 It's not only just a request, a reply will also be generated as he also needs to reply. 56:08.770 --> 56:15.100 For one thing, the request will be for one when R2 wants to communicate to R3, one side happens, 56:15.100 --> 56:19.240 but since R3 wants to reply back, he needs to know where R2 is private addresses. 56:19.270 --> 56:26.050 He needs a replies one more time R3, R2 wants to send two thing to R3. 56:26.050 --> 56:27.670 What is the packet going to look like? 56:31.040 --> 56:32.090 1.22. 56:37.980 --> 56:41.340 This is the inside packet outside. 56:41.340 --> 56:46.440 What is missing on the outside going from 26 to 2. 56:46.470 --> 56:48.720 This part is missing, so it needs this part. 56:48.960 --> 56:50.610 What does he do for this part? 56:52.980 --> 56:59.640 So request from 26.2 to 16.1 saying who is? 57:03.820 --> 57:04.030 One. 57:04.030 --> 57:04.480 Not kidding. 57:04.810 --> 57:15.820 The request goes out or one creates another request from 16.1 to 36.3. 57:16.840 --> 57:23.140 In this request will be who is 1.3 reply to. 57:28.740 --> 57:29.700 26 dot. 57:32.870 --> 57:34.880 This information will be inside the packet. 57:36.330 --> 57:36.500 Right. 57:36.560 --> 57:39.260 And this is if you check this is control plane traffic. 57:39.470 --> 57:40.510 There is no other header. 57:40.520 --> 57:42.050 There's only one publication. 57:42.410 --> 57:48.290 This will go back to R3 will reply and reply. 57:48.590 --> 57:50.120 I'm not talking about the packet. 57:50.150 --> 57:52.220 The ping has not even come here yet. 57:52.490 --> 58:04.130 The ping is still there, so R3 will send out a reply from 36.3 going to 26.2 because it was mentioned 58:04.130 --> 58:05.960 here saying I am 58:08.000 --> 58:10.880 168 .1.3. 58:11.480 --> 58:13.010 The reply goes straight back. 58:13.820 --> 58:17.810 It receives the public address which is 36.3. 58:18.110 --> 58:19.700 The whole concept is gone. 58:20.720 --> 58:25.490 In the actual header he's going to put what, 36 dot? 58:26.570 --> 58:28.100 So his side is complete. 58:29.660 --> 58:33.600 At the end of this you'll see the mapping has been resolved on R2, only on R2. 58:35.720 --> 58:36.230 The packet. 58:36.260 --> 58:41.740 Now the actual pink packet will go straight, right? 58:41.750 --> 58:45.510 He has 26.323 6.3. 58:45.530 --> 58:46.400 Go straight to. 58:46.820 --> 58:50.030 But our three needs to create a return packet. 58:50.030 --> 58:50.990 Going from where? 58:51.470 --> 58:52.610 1.32. 58:53.510 --> 58:59.450 The reply for that he knows his address is 36.3. 58:59.480 --> 59:01.610 He doesn't know what the address of 1.2 is. 59:03.950 --> 59:06.740 For that, he would send his own request. 59:07.040 --> 59:08.450 Request Reply. 59:08.480 --> 59:09.680 The whole process repeats. 59:10.520 --> 59:13.550 Once he has the mapping, it will stay there for two hours. 59:13.580 --> 59:14.270 For two hours. 59:14.270 --> 59:16.250 He doesn't need to contact the NHS at all. 59:17.660 --> 59:19.340 The whole system is set. 59:21.360 --> 59:34.230 Okay, let's have a look at the ping from our two to our three ping 192 168 1.0 goes through. 59:36.750 --> 59:37.450 This is Wireshark. 59:46.030 --> 59:47.740 This is the other one I need to check. 59:50.710 --> 59:53.990 This is from 3 to 6. 59:56.470 --> 59:57.190 1 to 6. 59:57.190 --> 59:58.540 This is the one which I want to check. 1:00:03.370 --> 1:00:06.340 26.2 to 16.1. 1:00:06.340 --> 1:00:07.060 What do you see? 1:00:08.680 --> 1:00:10.210 A resolution request. 1:00:12.220 --> 1:00:13.360 16.12. 1:00:13.360 --> 1:00:14.140 36.3. 1:00:14.170 --> 1:00:14.890 What do you see? 1:00:15.280 --> 1:00:16.870 Still a resolution request. 1:00:18.130 --> 1:00:18.390 Why? 1:00:18.430 --> 1:00:19.720 Still a resolution request? 1:00:19.900 --> 1:00:21.370 I got the request from one end. 1:00:21.520 --> 1:00:24.160 I forwarded the request to the other side. 1:00:24.580 --> 1:00:25.870 Who am I forwarding it to? 1:00:25.900 --> 1:00:26.950 36.3. 1:00:27.940 --> 1:00:29.860 I got a request from two R2. 1:00:30.910 --> 1:00:32.470 I received that request. 1:00:32.620 --> 1:00:35.050 Then I forwarded the request to 36 dot. 1:00:36.100 --> 1:00:38.350 You will also see a reply there. 1:00:39.790 --> 1:00:44.410 You also see a reply from R3 side. 1:00:44.410 --> 1:00:47.650 So if you check the other wireshark, the other capture. 1:00:50.230 --> 1:00:58.300 You should see a request coming from R1 to R3 and a reply going straight back. 1:01:02.370 --> 1:01:02.730 This one. 1:01:03.300 --> 1:01:03.900 It's not. 1:01:03.900 --> 1:01:05.490 It's too complicated of a protocol. 1:01:08.190 --> 1:01:08.730 Source. 1:01:09.720 --> 1:01:10.680 Source Protocol. 1:01:10.680 --> 1:01:11.370 Address. 1:01:12.120 --> 1:01:13.170 Destination Protocol. 1:01:13.170 --> 1:01:13.860 Address. 1:01:14.790 --> 1:01:15.240 Right. 1:01:15.480 --> 1:01:20.700 So he wants to go from 190 to 1, 68, 1.2 to 1.3. 1:01:23.970 --> 1:01:28.560 And the in the frame relation is the public address. 1:01:28.800 --> 1:01:32.010 So basically what I'm telling him is reply to 26.2. 1:01:33.540 --> 1:01:36.310 And you're saying this I told you in the packet it says reply to which guy. 1:01:36.330 --> 1:01:36.660 Right. 1:01:36.930 --> 1:01:38.820 You're saying reply to 26.3. 1:01:40.170 --> 1:01:43.680 So the reply will go to 26 directly to 26.2. 1:01:43.680 --> 1:01:47.910 So if you check from this end, you see the reply is going straight. 1:01:51.780 --> 1:01:51.910 Right. 1:01:53.640 --> 1:01:56.100 You know, What is it? 1:01:56.100 --> 1:01:58.500 The package would be in the packet. 1:01:58.530 --> 1:02:00.120 No, usually the packet is not. 1:02:00.510 --> 1:02:02.280 I remember the packet is not kept on hold. 1:02:03.030 --> 1:02:07.530 The packet goes through the hub first until the resolution takes place. 1:02:07.560 --> 1:02:10.290 The packet will go through the pink will go through the hub. 1:02:10.290 --> 1:02:11.880 The hub will forward the packet. 1:02:12.270 --> 1:02:15.060 There is no delay in. 1:02:15.540 --> 1:02:16.290 There is no delay. 1:02:17.400 --> 1:02:17.820 Unless. 1:02:18.060 --> 1:02:18.510 Until. 1:02:18.540 --> 1:02:18.930 Until. 1:02:18.930 --> 1:02:19.320 Until. 1:02:19.320 --> 1:02:22.560 Unless the hub resolves the issue, the packet will go to the hub. 1:02:22.560 --> 1:02:24.900 The hub will forward the packet just like it forwards. 1:02:24.900 --> 1:02:27.780 Any request you can see that. 1:02:27.780 --> 1:02:31.530 I think if you go to the first capture. 1:02:33.510 --> 1:02:33.930 There you go. 1:02:35.190 --> 1:02:35.580 Yeah. 1:02:37.290 --> 1:02:37.830 No, no, no. 1:02:38.520 --> 1:02:40.530 It doesn't go. 1:02:42.240 --> 1:02:42.840 It does. 1:02:44.430 --> 1:02:44.790 It does. 1:02:44.790 --> 1:02:46.050 The public address is the same. 1:02:46.050 --> 1:02:53.770 No, this is ICMP and IP has on top, but it doesn't have the IP internal IP is not there. 1:02:55.600 --> 1:02:56.140 It's not there. 1:02:56.170 --> 1:03:00.850 It's not the actual header that we are talking about because it is a part of interface tunnel zero. 1:03:00.850 --> 1:03:03.370 So you have the header, but it's not the source and destination. 1:03:03.700 --> 1:03:06.340 It's controlled by traffic, completely pure control plane. 1:03:07.850 --> 1:03:09.350 It doesn't work. 1:03:09.470 --> 1:03:10.670 It doesn't work. 1:03:10.760 --> 1:03:16.040 This is public to public going from one public address to the other. 1:03:16.040 --> 1:03:16.880 Public address. 1:03:17.060 --> 1:03:18.110 That's what you see here. 1:03:22.750 --> 1:03:22.920 Right. 1:03:23.440 --> 1:03:25.700 The first few packets are coming through here. 1:03:26.720 --> 1:03:29.570 You see double packets because it's coming in and going out. 1:03:30.620 --> 1:03:35.180 If you see this one will be going into that one and this one will be coming back from that one. 1:03:37.910 --> 1:03:41.420 36 to 16.1. 1:03:42.590 --> 1:03:45.620 Then again, 16.1 to 26.1. 1:03:48.110 --> 1:03:49.190 Not the request and the reply. 1:03:49.220 --> 1:03:51.950 See, the first packet in 1:03:54.680 --> 1:03:56.180 the packet has to go over here. 1:03:56.180 --> 1:03:56.630 Right. 1:03:56.750 --> 1:04:04.010 The ping will go from 192.168.1.2 to 1.3. 1:04:04.040 --> 1:04:05.000 It's going like that. 1:04:05.720 --> 1:04:12.710 The first time the public address that is going to be attached to this is going to be from 26.2 to 16.1 1:04:13.580 --> 1:04:17.150 because it's going to send it to the server. 1:04:17.480 --> 1:04:19.910 The server will check the mappings from the mappings. 1:04:19.910 --> 1:04:22.500 He realizes that it's not meant for 16.1. 1:04:22.500 --> 1:04:25.350 It's meant for from 16.12. 1:04:26.550 --> 1:04:31.590 So this is for the packet ICMP packet unless and until the ARP is get resolved. 1:04:31.680 --> 1:04:33.600 The moment gets resolved. 1:04:34.350 --> 1:04:36.090 They don't need to go through here anymore. 1:04:36.120 --> 1:04:37.390 That's why you see two of them. 1:04:37.410 --> 1:04:38.340 One is going in. 1:04:38.340 --> 1:04:39.240 One is coming out. 1:04:39.690 --> 1:04:40.800 That's why double. 1:04:44.230 --> 1:04:46.180 If you check this, you'll see double increase. 1:04:47.470 --> 1:04:52.990 Same 3.31 92 168 1.321.21.321.2. 1:04:52.990 --> 1:05:04.870 But actually is going from R3 to R1 publicly R3 to R1 and coming back out from R1 to R2. 1:05:10.530 --> 1:05:18.630 See your first spring package, which will go from 192.168 .1.2. 1:05:18.960 --> 1:05:20.040 Going out where? 1:05:22.540 --> 1:05:23.180 I'm not kidding. 1:05:24.010 --> 1:05:26.770 What is the public address that is going to be attached to this? 1:05:29.900 --> 1:05:32.050 Going from 26.2 to 16.1. 1:05:32.710 --> 1:05:33.640 This goes outside. 1:05:34.240 --> 1:05:35.800 This goes to R1 outside. 1:05:36.520 --> 1:05:36.840 This is. 1:05:38.020 --> 1:05:40.390 This is not I'm not talking about the big picture. 1:05:41.170 --> 1:05:42.520 I'm talking about the pink package. 1:05:44.350 --> 1:05:45.940 Before it gets resolved. 1:05:48.040 --> 1:05:49.190 Public to public and private. 1:05:49.210 --> 1:05:51.130 Actually, you want to go from private to private. 1:05:56.220 --> 1:05:56.890 Isn't it Right. 1:05:58.330 --> 1:05:59.530 Your pink goes from where? 1:05:59.560 --> 1:06:00.070 What do you pink? 1:06:00.070 --> 1:06:01.810 192 168, 1.3. 1:06:02.590 --> 1:06:03.760 The source is 192. 1:06:03.760 --> 1:06:04.240 168. 1:06:04.270 --> 1:06:05.410 This is an ICMP packet. 1:06:07.570 --> 1:06:10.240 The actual packet happens in the background. 1:06:10.390 --> 1:06:12.640 While this is happening in the chirp is also happening. 1:06:13.750 --> 1:06:15.550 This packet goes where to R1? 1:06:17.320 --> 1:06:17.610 Right. 1:06:17.620 --> 1:06:20.560 It's still ICMP going from 1.2 to 1 dot. 1:06:22.600 --> 1:06:33.500 I want realizes that the next hop is 36.3, so it's going to take the packet first, then create the 1:06:33.500 --> 1:06:34.190 same packet. 1:06:34.220 --> 1:06:41.600 He'll forward it from 16.1 to 36.3. 1:06:42.740 --> 1:06:45.930 But when it comes out, you'll see that it's still from 1.2 to 1.3. 1:06:45.950 --> 1:06:49.150 That's why on this link you'll see two duplicate packets. 1:06:49.160 --> 1:06:50.810 It's not actually duplicate packets. 1:06:50.840 --> 1:06:52.400 The public addresses are different. 1:06:52.670 --> 1:06:55.580 One is going from R2 to R1, then one is changing. 1:06:55.580 --> 1:06:57.650 It is going again from R1 to R3. 1:06:58.010 --> 1:07:00.800 But the actual packet is still from 1.2 to 1 dot three. 1:07:05.400 --> 1:07:05.850 Okay. 1:07:07.790 --> 1:07:11.570 If you want to do it just as it is, you don't have to do anything. 1:07:12.920 --> 1:07:14.870 If you just want to configure it, it's done already. 1:07:14.870 --> 1:07:16.460 They are communicating to each other. 1:07:17.450 --> 1:07:19.190 But to understand how it works is important. 1:07:21.760 --> 1:07:23.230 To understand how it works is important. 1:07:25.180 --> 1:07:25.480 Right. 1:07:27.100 --> 1:07:30.760 I'll repeat it again one last time. 1:07:32.410 --> 1:07:33.130 One last time. 1:07:33.490 --> 1:07:37.990 What happens is R2 wants to send a ping to R3. 1:07:39.280 --> 1:07:40.720 Wants to send a ping to R3. 1:07:41.050 --> 1:07:42.770 R2 doesn't have the mapping for R3. 1:07:42.790 --> 1:07:44.380 R3 doesn't have the mapping for R2. 1:07:44.410 --> 1:07:45.160 They don't know. 1:07:45.730 --> 1:07:46.750 They don't know each other. 1:07:47.320 --> 1:07:48.120 Specify what? 1:07:49.540 --> 1:07:49.940 Woman in. 1:07:50.590 --> 1:07:53.420 And when I say something is going through the tunnel. 1:07:53.440 --> 1:07:54.370 What is tunnel? 1:07:54.400 --> 1:07:59.050 Tunnel means you have an internal IP header and an external IP header. 1:08:01.210 --> 1:08:05.500 When you have an internal IP header and an external IP header, that means this tunnel is getting this 1:08:05.500 --> 1:08:06.340 traffic is tunnel. 1:08:08.300 --> 1:08:08.690 Okay. 1:08:09.350 --> 1:08:11.420 That's first this differentiation. 1:08:11.510 --> 1:08:15.890 Now, when you are pinging, how does your ping look like? 1:08:19.350 --> 1:08:20.160 They have the. 1:08:20.790 --> 1:08:21.200 And. 1:08:21.210 --> 1:08:21.660 No, I don't. 1:08:23.010 --> 1:08:24.780 How does your thing look like? 1:08:30.330 --> 1:08:31.380 I said, this is it. 1:08:32.970 --> 1:08:33.510 Okay. 1:08:33.630 --> 1:08:34.560 This is your ICMP. 1:08:37.760 --> 1:08:39.110 He wants to go from where? 1:08:41.060 --> 1:08:46.580 1.22 to remember this is 192 168. 1:08:46.820 --> 1:08:49.730 When I write something in blue, it's 192 168. 1:08:49.970 --> 1:08:51.740 Brown would be the outside hitter. 1:08:52.760 --> 1:08:54.620 This will be encapsulated with gray. 1:08:56.330 --> 1:09:00.650 Source will be destination. 1:09:00.680 --> 1:09:02.060 What destination do I put? 1:09:05.830 --> 1:09:07.540 He doesn't know the destination, right? 1:09:07.840 --> 1:09:10.270 It's not going to drop the packet or buffer it. 1:09:11.560 --> 1:09:13.300 It's not going to drop or buffer it. 1:09:13.330 --> 1:09:21.250 It's going to send it where to R1 It's going to send it to R1, Which is what? 1:09:24.620 --> 1:09:27.020 16, not the packet. 1:09:27.020 --> 1:09:28.310 He doesn't want to drop the packet. 1:09:28.310 --> 1:09:31.580 The packet goes to R1, sees the packet. 1:09:31.580 --> 1:09:34.100 Since it's meant for him, it opens the packet. 1:09:35.030 --> 1:09:36.990 This packet, does it go. 1:09:38.330 --> 1:09:38.840 This packet? 1:09:38.840 --> 1:09:41.060 Yeah, it is done on two IPS, right? 1:09:43.160 --> 1:09:45.200 No, this is not an this is an actual ping. 1:09:45.800 --> 1:09:48.470 The actual ping has not come out yet. 1:09:49.640 --> 1:09:51.350 I'm explaining how the ping goes. 1:09:51.620 --> 1:09:52.790 What happens to the ping? 1:09:52.820 --> 1:09:53.840 It's not dropped. 1:09:54.350 --> 1:09:55.730 It is still forwarded. 1:09:55.910 --> 1:10:01.540 Even if your IP is not resolved even right now, it's not resolved. 1:10:01.550 --> 1:10:01.910 Right. 1:10:02.210 --> 1:10:03.830 But the ping is still going. 1:10:04.010 --> 1:10:04.550 How? 1:10:04.580 --> 1:10:07.430 Now, when our one receives it, it checks. 1:10:07.430 --> 1:10:09.170 It's going from 1.2 to 1.3. 1:10:09.170 --> 1:10:11.690 But this by itself, he is 1.1. 1:10:11.690 --> 1:10:13.550 So it's not meant to him for him. 1:10:14.780 --> 1:10:15.740 So it sees. 1:10:15.740 --> 1:10:17.300 Okay, it wants to go to 1.3. 1:10:17.300 --> 1:10:23.350 What is the destination of 1.3 36 dot the source. 1:10:23.360 --> 1:10:33.950 It keeps it as itself 16.1 forwards the packet where 2 or 3 three receives the packet opens it completely. 1:10:38.080 --> 1:10:41.800 Creates a reply packet going from where to where? 1:10:42.430 --> 1:10:43.660 1.321. 1:10:43.660 --> 1:10:44.200 Dot. 1:10:48.770 --> 1:10:50.360 Does it know where 1.2 is? 1:10:50.990 --> 1:10:51.360 It doesn't. 1:10:51.380 --> 1:10:54.020 Where is it going to send it to, again? 1:10:54.020 --> 1:10:54.830 16.1. 1:10:55.980 --> 1:10:56.870 So you'll see. 1:10:57.440 --> 1:10:58.580 Source will be. 1:10:59.960 --> 1:11:05.450 So your return packet, your ping packet will also come to 16.1 16.1. 1:11:05.520 --> 1:11:07.350 You will see the destination is 1.2. 1:11:07.370 --> 1:11:10.640 Change it with going from 16.1 to. 1:11:11.690 --> 1:11:17.240 So your actual ping, which should have been as simple as this until your end is resolved. 1:11:17.240 --> 1:11:18.830 It's not as simple as that. 1:11:19.280 --> 1:11:20.220 It goes through the hub. 1:11:20.240 --> 1:11:21.350 It's like a man in the middle. 1:11:22.700 --> 1:11:24.110 So it goes like that. 1:11:24.140 --> 1:11:30.920 The reply also comes like for ICMP before, before the IP. 1:11:31.040 --> 1:11:31.950 This is how it goes. 1:11:31.970 --> 1:11:33.290 But at the moment this happens. 1:11:33.330 --> 1:11:35.600 R2 realizes that he needs to resolve the mapping. 1:11:37.040 --> 1:11:38.960 He doesn't want to send all the traffic through the hub. 1:11:39.320 --> 1:11:43.490 Then an ARP resolution request is sent from R2. 1:11:44.990 --> 1:11:47.550 R2 will say, Listen, I want an ARP. 1:11:53.030 --> 1:11:59.360 NHLPA resolution request where it says now this is not a tunnel, traffic resolution is not a tunnel. 1:12:00.380 --> 1:12:01.650 It doesn't look like this. 1:12:01.670 --> 1:12:07.640 I'll do it right down here so that you know, the difference between the two and a request is going 1:12:07.640 --> 1:12:08.630 to look like this. 1:12:11.280 --> 1:12:11.940 Talk to me. 1:12:12.300 --> 1:12:16.410 Something that happens after the after the after. 1:12:16.410 --> 1:12:18.050 The thing is not successful. 1:12:18.060 --> 1:12:19.530 The first you send five. 1:12:19.560 --> 1:12:20.030 Right. 1:12:20.220 --> 1:12:23.040 But then it takes a little while to generate the request. 1:12:23.190 --> 1:12:25.410 Until then, 1 or 2 pigs have left already. 1:12:25.830 --> 1:12:27.570 So the first cycle is complete silence. 1:12:28.200 --> 1:12:29.130 I got replies. 1:12:29.790 --> 1:12:31.080 But that's only one thing, right? 1:12:31.080 --> 1:12:31.950 How many have you sent? 1:12:33.900 --> 1:12:35.170 It's like our pride. 1:12:35.220 --> 1:12:36.300 Our puts it on buffer. 1:12:36.330 --> 1:12:37.890 That's why I wanted two packets are dropped. 1:12:39.330 --> 1:12:41.670 It doesn't want to drop that 1 or 2 packets. 1:12:43.710 --> 1:12:45.840 You understand art doesn't have the destination market. 1:12:45.960 --> 1:12:50.100 So what does art do that keeps it on hold and waits for the ping to complete? 1:12:50.820 --> 1:12:54.390 Best for the art to come back until that time, the ICMP times out. 1:12:55.050 --> 1:12:56.640 I don't want to time that out here. 1:12:56.640 --> 1:12:57.180 I want. 1:12:57.210 --> 1:12:59.130 If you don't have the mapping, send it to the server. 1:12:59.130 --> 1:13:00.060 He'll manage it. 1:13:00.690 --> 1:13:03.810 He'll send it to the actual destination until your mappings get resolved. 1:13:06.570 --> 1:13:07.800 Are you asking 1:13:11.730 --> 1:13:13.290 if I will be going to reply. 1:13:13.290 --> 1:13:16.050 Will also be going to either the. 1:13:16.530 --> 1:13:17.040 Yes. 1:13:17.040 --> 1:13:21.030 Even as long as R3 has not resolved its mapping, the reply will come from other. 1:13:23.750 --> 1:13:27.200 R2 will send the request from R1 and R2 will also reply back from R1. 1:13:27.440 --> 1:13:33.350 R3 will also reply back from As long as both sides have not resolved their mappings to resolve the mappings. 1:13:33.380 --> 1:13:35.270 The app looks like this. 1:13:35.480 --> 1:13:39.650 Who is 1.3? 1:13:41.980 --> 1:13:43.120 What's the final thing is? 1:13:43.750 --> 1:13:44.590 Yeah, both of them. 1:13:45.370 --> 1:13:46.810 That's what you see in Wireshark. 1:13:46.840 --> 1:13:48.070 They are simultaneous. 1:13:50.560 --> 1:13:54.210 You check things are also going resolution request is also in the. 1:13:56.800 --> 1:13:57.370 This is the pink. 1:13:58.000 --> 1:13:59.470 This is the resolution request. 1:13:59.800 --> 1:14:01.630 They both come out together, actually. 1:14:01.870 --> 1:14:02.890 The pink comes out. 1:14:02.890 --> 1:14:04.270 The resolution request comes out. 1:14:04.660 --> 1:14:07.960 As long as the resolution request is not replied with, the pink will go through the hub. 1:14:09.130 --> 1:14:10.840 The moment it is replied, they'll go directly. 1:14:13.360 --> 1:14:13.900 Okay. 1:14:14.020 --> 1:14:15.540 So we see a change in. 1:14:16.480 --> 1:14:22.540 First off, what do these do you mean? 1:14:25.920 --> 1:14:26.030 Are. 1:14:26.980 --> 1:14:28.020 This one. 1:14:28.270 --> 1:14:36.120 This one is going from 2 to 1, then the other one is coming back from R1, R2, R3, R1 acts as a mediator. 1:14:36.400 --> 1:14:38.410 So it is acting as a mediator, right? 1:14:38.440 --> 1:14:44.800 It's actually going from 1.2 to 1.3, but first it enters R1, then it leaves from R1. 1:14:48.890 --> 1:14:49.370 Guilleuma. 1:14:51.160 --> 1:14:53.410 This is the ping request. 1:14:53.440 --> 1:14:55.600 Ping request going from 2 to 3. 1:14:56.110 --> 1:14:57.530 But first is going from where? 1:14:57.550 --> 1:14:59.350 26.2 to 16.1. 1:15:00.670 --> 1:15:04.570 Then from 16.1 to 36. 1:15:04.870 --> 1:15:07.990 Same request coming in, going out. 1:15:08.020 --> 1:15:09.400 Then goes back to the destination. 1:15:10.480 --> 1:15:14.560 Same thing happens to the reply coming from 36.3 to 16.1. 1:15:14.680 --> 1:15:17.020 Then from 16.1 to 26.2. 1:15:18.490 --> 1:15:20.440 Coming in from one end, going to the other side. 1:15:20.440 --> 1:15:21.350 Coming in from this side. 1:15:21.370 --> 1:15:22.330 Going to the other side. 1:15:22.360 --> 1:15:24.970 In the meantime, resolution request has also come through. 1:15:26.440 --> 1:15:28.270 How does the resolution request look like? 1:15:29.050 --> 1:15:30.220 Who is 1.3? 1:15:30.520 --> 1:15:32.950 And this is not tunnel traffic. 1:15:34.090 --> 1:15:35.530 So there is no IP inside here. 1:15:36.040 --> 1:15:38.290 This is just control plane asking who is this guy? 1:15:40.360 --> 1:15:41.110 Who is this guy? 1:15:41.140 --> 1:15:43.300 Right on top of that. 1:15:43.330 --> 1:15:45.370 What I'll do is I'll add a header. 1:15:48.630 --> 1:15:55.920 This request will go straight to the server from 26.2 going to. 1:15:59.120 --> 1:16:00.830 The state request to the server. 1:16:01.250 --> 1:16:04.970 Listen, man, I want to know where 1.3 is. 1:16:05.000 --> 1:16:06.800 This is a resolution request. 1:16:07.550 --> 1:16:09.830 I'm sending packets to him, but I'm sending it through you. 1:16:09.830 --> 1:16:11.210 I don't want to send it through you. 1:16:11.240 --> 1:16:12.920 Please tell me where that guy is. 1:16:12.950 --> 1:16:14.690 What does one do with this packet? 1:16:21.720 --> 1:16:24.400 Sauer to R3, but adds another piece of information in there. 1:16:24.420 --> 1:16:24.930 What? 1:16:28.070 --> 1:16:29.000 I will forward it. 1:16:29.000 --> 1:16:33.140 But add another piece of information here saying. 1:16:34.810 --> 1:16:38.260 Reply 226 dot. 1:16:42.420 --> 1:16:43.410 The request comes here. 1:16:46.100 --> 1:16:46.970 The reply. 1:16:48.190 --> 1:16:51.290 Now, the request will not look from 26.2 to 16.1. 1:16:51.320 --> 1:16:56.450 The request will be from 16.1 to 36 point. 1:17:00.370 --> 1:17:01.480 The request comes. 1:17:01.690 --> 1:17:03.880 It says, Who is are you? 1:17:03.910 --> 1:17:05.680 192 168 1.3. 1:17:06.160 --> 1:17:17.890 If you are reply to 26.2 send as we call it, resolution reply, send a resolution reply back to $26. 1:17:19.030 --> 1:17:22.120 The resolution reply is generated on our three. 1:17:32.480 --> 1:17:46.190 Resolution reply says okay, I am on 92 168 .1.3 My source Just like earlier resolution requests and 1:17:46.190 --> 1:17:52.790 reply used to take place by actual source is 36.3 and I'm going to 26.2. 1:17:52.790 --> 1:17:54.290 So it goes to 26.2 times. 1:17:54.380 --> 1:17:59.240 Listen, I am I am on 9268 1.3. 1:17:59.270 --> 1:18:02.360 So later now I want to send a packet to 168. 1:18:02.360 --> 1:18:05.150 1.3 is is going to send it directly to. 1:18:08.660 --> 1:18:09.350 $36. 1:18:09.740 --> 1:18:11.330 And that's what you see now. 1:18:11.420 --> 1:18:19.160 All the other corresponding packets which come out from R3 or R2, will not go through the hub. 1:18:21.590 --> 1:18:22.220 This is the hub. 1:18:22.850 --> 1:18:26.480 They don't go through the hub as many number of packets you send. 1:18:27.380 --> 1:18:28.790 It will never go through the hub again. 1:18:29.190 --> 1:18:30.470 It doesn't need to go through the hub. 1:18:33.120 --> 1:18:33.410 Right. 1:18:34.410 --> 1:18:37.650 If you check they're all going spoke to spoke directly. 1:18:42.480 --> 1:18:43.050 Spoke to Spoke. 1:18:43.050 --> 1:18:43.290 Right. 1:18:46.080 --> 1:18:49.910 It applies from 3 to 2 is the old one. 1:18:57.550 --> 1:19:01.220 There as many packets as you send now they will go straight. 1:19:10.700 --> 1:19:13.600 Why take this out on R2? 1:19:14.720 --> 1:19:21.620 R2, I have a static mapping for the server. 1:19:21.950 --> 1:19:23.810 I also have a dynamic mapping. 1:19:25.460 --> 1:19:26.360 For whom? 1:19:29.390 --> 1:19:30.170 How did I get it? 1:19:30.170 --> 1:19:31.820 I sent a resolution request. 1:19:32.390 --> 1:19:33.860 Request went to the other side. 1:19:33.890 --> 1:19:34.970 The guy replied to me. 1:19:37.490 --> 1:19:42.830 There are two different things and this time the two request request reply. 1:19:43.670 --> 1:19:48.290 In the meantime, the ping will also go through the hub the same way. 1:19:49.910 --> 1:19:54.550 The moment the request reply comes to me, I have the destination address directly. 1:19:54.560 --> 1:19:58.280 Now the ping will not go to the server now it will go direct. 1:20:03.910 --> 1:20:04.840 Any questions? 1:20:10.660 --> 1:20:12.040 Well is sending the packet first. 1:20:12.070 --> 1:20:15.670 His request was Rover initiates the session. 1:20:17.480 --> 1:20:19.680 We check our tools, R3 will also be resolved. 1:20:21.020 --> 1:20:24.660 So it is also resolved. 1:20:30.010 --> 1:20:33.550 One 168 1.24 R3 is absorbed as well as four R2. 1:20:33.700 --> 1:20:34.810 Both sides resolved. 1:20:38.620 --> 1:20:39.610 Any questions? 1:20:42.610 --> 1:20:43.150 No questions. 1:20:46.040 --> 1:20:46.750 Only two hours. 1:20:48.490 --> 1:20:52.300 The whole process will start again after two hours. 1:20:52.300 --> 1:20:52.960 The whole process. 1:20:52.960 --> 1:20:54.250 The first things will go through. 1:20:54.250 --> 1:20:57.580 The hub request will be sent, reply will come back. 1:20:57.580 --> 1:21:00.460 But it's a very small process, just 2 or 3 packets. 1:21:00.940 --> 1:21:02.830 It happens within two seconds. 1:21:03.940 --> 1:21:07.600 The whole process of request reply happens within two seconds. 1:21:10.280 --> 1:21:11.840 By the end of that post. 1:21:12.050 --> 1:21:13.040 Communication is there. 1:21:13.070 --> 1:21:17.570 The good thing is I did not need to configure anything I can communicate anywhere. 1:21:20.210 --> 1:21:23.810 1.4 and we send out a packet to 1.4. 1:21:25.910 --> 1:21:28.010 You'll see for resolution requests. 1:21:31.740 --> 1:21:31.970 Right. 1:21:31.980 --> 1:21:33.060 I told you both ways. 1:21:33.420 --> 1:21:34.440 One is this way. 1:21:34.620 --> 1:21:38.670 The other is so this way and this way. 1:21:41.820 --> 1:21:43.800 One resolution request comes from R4. 1:21:44.700 --> 1:21:45.900 Forward it to R3. 1:21:46.380 --> 1:21:48.420 The other resolution request comes from R3. 1:21:48.450 --> 1:21:50.940 Forward it to R4 because both sides mapping should be resolved. 1:21:50.940 --> 1:21:51.240 Right? 1:21:52.770 --> 1:21:55.800 The whole process is repeating and you see some things going up and down here. 1:21:57.060 --> 1:21:57.780 Two things. 1:21:58.170 --> 1:22:00.060 Only one, this was even quicker than that. 1:22:00.960 --> 1:22:02.400 Only one thing went through the hub. 1:22:03.810 --> 1:22:08.180 Again, I want to go to 1.5, see the hub again. 1:22:11.520 --> 1:22:12.000 Resolution. 1:22:12.000 --> 1:22:12.370 Request. 1:22:12.390 --> 1:22:13.170 Resolution Request. 1:22:13.200 --> 1:22:14.010 Resolution Request. 1:22:14.040 --> 1:22:14.730 Resolution. 1:22:16.410 --> 1:22:17.160 Resolution Request. 1:22:17.190 --> 1:22:17.990 Resolution request. 1:22:18.000 --> 1:22:19.080 You already has the other one. 1:22:23.260 --> 1:22:23.510 Right. 1:22:23.740 --> 1:22:25.480 By the time this is done, you'll see. 1:22:27.220 --> 1:22:32.950 So it has everything because everybody communicated to him. 1:22:34.570 --> 1:22:36.340 Imagine how scalable this is. 1:22:38.330 --> 1:22:39.430 What scalable. 1:22:39.440 --> 1:22:41.360 I did not configure anything on the scope. 1:22:41.450 --> 1:22:42.410 This is all I did. 1:22:44.840 --> 1:22:45.670 That's all I did. 1:22:45.680 --> 1:22:48.620 I just told them to register to the NHS. 1:22:48.650 --> 1:22:54.170 All of them registered and the good thing for them the NHS is like your godfather. 1:22:54.470 --> 1:22:57.890 For them it's like community NHS. 1:22:57.930 --> 1:22:59.210 R1 is the Godfather. 1:23:00.260 --> 1:23:03.420 Now they want to talk to each other and they don't know the address of the guy. 1:23:03.440 --> 1:23:04.850 They will go to the Godfather. 1:23:06.410 --> 1:23:09.960 They go to the NHS and tell me where this guy is. 1:23:09.980 --> 1:23:10.880 The NHS forwards. 1:23:10.880 --> 1:23:13.970 The request tells the other guy, Hey, listen, please talk to him. 1:23:14.750 --> 1:23:16.130 Go and tell him where you live. 1:23:17.450 --> 1:23:20.210 He doesn't go back to him and tells him, Listen, this is the guy. 1:23:20.240 --> 1:23:20.780 No. 1:23:20.780 --> 1:23:22.050 I ask him, Where is this guy? 1:23:22.070 --> 1:23:22.850 I'll go to the other guy. 1:23:22.880 --> 1:23:24.180 Listen, please reply to that guy. 1:23:24.200 --> 1:23:25.010 I don't have time. 1:23:26.420 --> 1:23:28.380 Then the other guy asked me, Do you know where this guy is? 1:23:28.400 --> 1:23:29.000 I'll go to him. 1:23:29.000 --> 1:23:29.360 I'll tell him. 1:23:29.360 --> 1:23:30.590 Listen, reply to this guy. 1:23:32.330 --> 1:23:33.170 So it's a cycle. 1:23:34.070 --> 1:23:34.940 Think of it as a loop. 1:23:35.510 --> 1:23:35.990 Request. 1:23:35.990 --> 1:23:36.410 Request. 1:23:36.410 --> 1:23:37.040 Reply. 1:23:37.290 --> 1:23:37.830 Request. 1:23:37.830 --> 1:23:38.280 Request. 1:23:38.280 --> 1:23:38.730 Reply. 1:23:40.020 --> 1:23:41.280 Total of six packets. 1:23:42.000 --> 1:23:43.110 The hub will see four. 1:23:43.830 --> 1:23:44.940 The spokes will see two. 1:23:49.260 --> 1:23:51.620 There is this part clear. 1:23:51.630 --> 1:23:53.190 This is complete DMV. 1:23:55.600 --> 1:24:00.910 We still have not created the communication set yet, but most of your dmvpn concepts are done here. 1:24:01.780 --> 1:24:04.450 The single hub, be it dual hub if you understand this part. 1:24:05.890 --> 1:24:06.730 Let's take a break. 1:24:06.760 --> 1:24:07.870 Now is 1015. 1:24:08.680 --> 1:24:10.030 Let's take a 15 minutes break.