1 00:00:11,050 --> 00:00:19,300 This is one of multiple IP addressing and submitting scenarios rather than just working out the subnets 2 00:00:19,360 --> 00:00:20,880 for a scenario. 3 00:00:21,220 --> 00:00:28,330 We can work them out and then configure the devices so that we can practically design and configure 4 00:00:28,750 --> 00:00:30,480 a Cisco IP network. 5 00:00:31,400 --> 00:00:37,400 OK so now that we've worked out the subnets we need to configure the devices in our network. 6 00:00:37,430 --> 00:00:45,760 Let's assume that these switches are Layer 2 switches the local area networks need to support up to 7 00:00:45,760 --> 00:00:52,580 60 hosts including an IP address allocated to the switches and the routers. 8 00:00:52,900 --> 00:00:59,590 So let's start with a one on the first Ethan and interface. 9 00:01:00,010 --> 00:01:02,910 I'm going to shut the interface. 10 00:01:03,400 --> 00:01:11,170 We need to configure an IP address so 1 2 1 6 8 1 and this is why subsetting is so important. 11 00:01:11,520 --> 00:01:14,530 What address are we going to allocate to the Rodda. 12 00:01:14,530 --> 00:01:20,920 So the network we are using is 1 2 1 6 8 1.0 slice 26. 13 00:01:21,000 --> 00:01:24,910 So let's see we want to use the last IP address for the router. 14 00:01:26,080 --> 00:01:32,500 What is the first IP address and last IP address in the subnet. 15 00:01:32,720 --> 00:01:37,440 So therefore addresses that we need to think about we need to think about the subnet address thats 1 16 00:01:37,450 --> 00:01:41,690 on 2 1 6 8 1 0 is like 26. 17 00:01:41,720 --> 00:01:45,380 Then we need to work out the first IP address. 18 00:01:45,550 --> 00:01:52,610 Well first host that can be allocated then we need to work out the last IP address and we need to work 19 00:01:52,610 --> 00:01:55,530 out what the broadcast address is. 20 00:01:55,540 --> 00:02:04,780 So we already have the subnet address to work out the first IP address what you do is you set all binary 21 00:02:05,230 --> 00:02:10,760 bits to 0 in the host portion except for the last bit. 22 00:02:10,800 --> 00:02:16,640 So if you look at this that equates to 1 in decimal. 23 00:02:16,700 --> 00:02:22,220 So the first host will be 1 9 2 1 6 8 1 1 slice 26 24 00:02:25,040 --> 00:02:26,660 is our subnet. 25 00:02:26,720 --> 00:02:36,700 Is our first host to work out to the last address in the subnet you fold the host portion only the host 26 00:02:36,700 --> 00:02:39,440 portion with binary ones. 27 00:02:39,640 --> 00:02:46,740 Except for the last but which is set to binary 0. 28 00:02:47,190 --> 00:02:54,010 So notice the host portion is fulled with binary ones except for the last but. 29 00:02:54,200 --> 00:02:55,400 So what does this equal. 30 00:02:55,430 --> 00:03:08,140 Its 32 plus 16 which is 48 plus 8 which is 56 plus 4 which is 60 plus 2 which is 62. 31 00:03:08,950 --> 00:03:14,900 So that equals 62 slash 26. 32 00:03:15,060 --> 00:03:17,600 And what is the broadcast address equal to. 33 00:03:18,150 --> 00:03:23,910 Now talk about easier ways to work this out but lets work it out as follows. 34 00:03:23,910 --> 00:03:30,600 So to work out the broadcast what you do is you fool the host portion with binary ones and that will 35 00:03:30,600 --> 00:03:39,090 give you 63 slash 26 so you can either count up all these bets or you do it in reverse. 36 00:03:39,090 --> 00:03:43,580 You say it's 255 minus 128 minus 64. 37 00:03:43,580 --> 00:03:47,010 This is why it's good to have this in the exam. 38 00:03:47,010 --> 00:03:53,420 So when you go to the exam write this stone so that you can work out the values. 39 00:03:53,460 --> 00:03:58,330 So this address is a cost address so we can't allocate that to the Rodda. 40 00:03:58,470 --> 00:04:02,780 But what we can do is allocate the last IP address to the Rodda. 41 00:04:02,930 --> 00:04:13,290 So the routing needs to be configured as 1 to 1 6 8 1 62 and the mosque is 2 4 5 2 4 5 2 for 5 1. 42 00:04:13,430 --> 00:04:29,150 Remember the mosque is 2:55 255 255 192 IP address again is 1 9 2 1 6 8 1 62 which is what we've configured 43 00:04:29,150 --> 00:04:29,870 on the router. 44 00:04:29,960 --> 00:04:31,620 So I can press enter. 45 00:04:32,240 --> 00:04:41,430 So we've now configured the router and as an example we should be able to paying ourselves which we 46 00:04:41,430 --> 00:04:46,940 can and if we're paying 63 that is actually a broadcast 47 00:04:49,550 --> 00:04:53,130 so show IP interface Fost. 48 00:04:53,140 --> 00:05:03,730 Ethan It was 0 0 notice the Rotty is configured as follows IP addresses 1 9 2 1 6 8 162 slushed 26. 49 00:05:03,730 --> 00:05:11,840 This is all hostes on my quick approved cost but this is a local subnet to provide cost. 50 00:05:11,860 --> 00:05:18,430 So again show run interface if serious slash if there is zero there is our configuration. 51 00:05:18,460 --> 00:05:20,320 Now we need to configure the hosts 52 00:05:25,460 --> 00:05:34,620 and let's assume that we are going to configure the first host using the first IP address in the subnet. 53 00:05:34,620 --> 00:05:36,930 So it's 1 9 2 1 6 8 1 54 00:05:40,610 --> 00:05:46,280 so it needs to be configured as 1 9 2 1 6 8 1 1 slashed 26. 55 00:05:46,380 --> 00:05:59,640 So 1.1 some of that mosque is 2 4 5 2 5 2 for 5 or 92 default gateway is 62 and all set the DNS to the 56 00:05:59,640 --> 00:06:10,220 default gateway click safe lets start up that host and open up a console to the host. 57 00:06:10,250 --> 00:06:11,290 So here it is. 58 00:06:11,290 --> 00:06:18,170 I have config is zero IP address of the host is configured as follows. 59 00:06:19,980 --> 00:06:21,790 Mosque is set to the following. 60 00:06:21,790 --> 00:06:27,390 So Ping 1 on 2 1 6 8 1 2 1 and ping itself can we ping the router. 61 00:06:27,510 --> 00:06:29,100 Yes we can. 62 00:06:29,100 --> 00:06:35,380 Not to prove that we could do de-bug IP ICMP and ping from the host to the router. 63 00:06:35,670 --> 00:06:40,860 You can see the pings are succeeding and we are getting it debug on the router. 64 00:06:40,890 --> 00:06:41,990 Turn off the Debug. 65 00:06:42,180 --> 00:06:52,160 Ping 1 on 2 1 6 8 1 2 1 Rodek and ping the first PC show on the interface brief again. 66 00:06:52,370 --> 00:06:54,140 This is the IP address of the router. 67 00:06:54,260 --> 00:06:57,440 Lets configure the second PC 61 68 00:07:00,350 --> 00:07:03,880 so configure that statically 69 00:07:10,100 --> 00:07:22,410 61 subnet mask 255 255 255 192 Rodda sixty two will set to the DNS to the Rodda 70 00:07:26,340 --> 00:07:30,850 and stalked the PC up and open up a console. 71 00:07:30,910 --> 00:07:42,940 So here's a boon to two PC to I-F config ethe zero IP address is 61 subnet mask is this Can we paying 72 00:07:43,710 --> 00:07:45,100 the Rodda. 73 00:07:45,730 --> 00:07:46,510 Yes we can. 74 00:07:46,510 --> 00:07:47,790 Can we ping the other host. 75 00:07:47,790 --> 00:07:49,580 Yes we can. 76 00:07:49,610 --> 00:07:53,900 So we've configured the IP addresses on the subnet. 77 00:07:53,930 --> 00:07:54,870 Now one last test. 78 00:07:54,890 --> 00:07:57,810 Let's ping the broadcast address. 79 00:07:57,830 --> 00:08:05,500 Notice the option we are told that we have to explicitly specify broadcast and when I broadcast the 80 00:08:05,500 --> 00:08:10,220 router actually replies to that broadcast the other host doesn't. 81 00:08:10,480 --> 00:08:20,320 But we are pinging the broadcast address when we use 63 so the broadcast isn't 1 9 2 1 6 8 1 255 the 82 00:08:20,330 --> 00:08:24,990 broadcast address for the subnet is 1 9 2 1 6 8 1 63. 83 00:08:25,010 --> 00:08:29,450 So we have successfully configured this subnet. 84 00:08:29,450 --> 00:08:35,330 Now we need to configure the subnet and this gets a little bit more interesting because it's 1 9 2 1 85 00:08:35,330 --> 00:08:39,110 6 8 1 64 slice 26. 86 00:08:39,110 --> 00:08:40,990 Hope you found this video useful. 87 00:08:41,090 --> 00:08:46,550 If it was of benefit to you please like it and please subscribe to my YouTube channel. 88 00:08:46,880 --> 00:08:48,500 I wish you all the very best.