Uncomplicated Ways Of Subnetting Cast B Ip Addresses

In my previous post, I shared how nosotros tin subnet a shape C address amongst an example. In this post, I volition portion how to subnet a shape B address amongst 2 examples. Since shape B uses 2 octets for the host bit, I volition present 2 examples ane from each octets. Let's larn going.




Range of shape B address: get-go of all, live reminded that whatsoever IP whose values inwards the get-go octet autumn betwixt 128 too 191, is a shape B address.



Example 1: Given 172.16.12.0/19, decide the following:

(i) The seat out of subnets that the given address too subnetmak volition produce.

(ii) The seat out of hosts per each of the subnets generated inwards (i) inwards a higher house

(iii) Using a table, listing all subnets, get-go too end valid IPs, too broadcast address



First affair to attain is write the subnetmask from the given slash notation: /19 volition live 255.255.224.0 (8 bits on is 255 too iii bits on is 224, remember?)



Answers:



(i) To decide the seat out of subnets, role 2^X, where X is equal to the seat out of bits borrowed. This volition laissez passer 2^3=8 (the default subnetmask for B is sixteen but inwards this example, nosotros are given /19, pregnant that nosotros borrowed 3.) So our seat out of subnets volition live 8. Question ane answered.

You may likewise like: Subnetting shape H5N1 address, on my side past times side post



(ii) To decide the seat out of host per subnet, role 2^Y-2, where Y equals the seat out of bits off. This volition laissez passer 32-19=13 (IPv4 is a 32-bit address format too inwards this example, nineteen bits are turned on) Now, that volition convey xiii off, nosotros volition substitute that into the equation, giving us 2^13-2=8,190. We volition convey 8,190 hosts per subnets (the -2 is for the network too broadcast addresses that nosotros can't assign to hosts on the networks).

(iii) To listing out the subnets, nosotros volition demand a block size. Block size=256-224, which gives us 32. (to larn your block size, precisely substitute the value of the subnet bits from 256. 256 is a constant value). Now, that nosotros convey a block size of 32, nosotros tin listing our subnets inwards block size of 32, starting from subnet zip (back inwards the days, IP subnet zip was non used except yous plow it on yourself on the router. Now, IP subnet zip is turned past times default too so, yous tin role the zip subnet)

Subnet	0.0	32.0	64.0	96.0	128.0	160.0	192.0	224.0
First IP	0.1	32.1	64.1	96.1	128.1	160.1	192.1	224.1
Last IP	31.254	63.254	95.254	127.254	159.254	191.254	223.254	255.254
Broadcast	31.255	63.255	95.255	127.255	159.255	191.255	223.255	255.255

Example 2. Given 172.16.0.0/26, decide the following:

(i) Number of unique subnets that the given address too subnetmask volition create

(ii) Number of hosts per subnet

(iii) List all subnets, valid IP addresses too their broadcast.



I chose /26 because amongst it, the subnet flake falls into the 4th octet, which volition live unlike from the get-go instance where it barbarous into the 3rd octet.

First, the subnetmask volition live 255.255.255.192



Answers:



(i) Number of subnet volition live 2^X where X equals the seat out of borrowed bits. This volition laissez passer us 2^10=1024 (again, the default for shape B is sixteen but inwards this example, nosotros convey /29. So when yous substitute sixteen from 29, yous convey 10). Answer to query (i) is 1024 subnets.



(ii) How many hosts per subnet? To larn this, nosotros role the formula 2^Y-2 where Y equals the seat out of off bits. This gives us 2^6-2=62 (again, IPV4 is a 32-bit address too nosotros are given /29. That leaves us amongst vi bits off).

(iii) Block size volition live 256-192 which volition laissez passer us 62. With that, nosotros listing our subnets inwards blocks of 62.

First viii subnets

Subnet	0.0	0.64	0.128	0.192	1.0	1.64	1.128	1.192
First IP	0.1	0.65	0.129	0.193	1.1	1.65	1.129	1.193
Last IP	0.62	0.126	0.190	0.254	1.62	1.126	1.190	1.254
Broadcast	0.63	0.127	0.191	0.255	1.63	1.127	1.191	1.255

Last viii subnets

Subnet	254.0	254.64	254.128	254.192	255.0	255.64	255.128	255.192
First IP	254.1	254.65	254.129	254.193	255.1	255.65	255.129	255.193
Last IP	254.62	254.126	254.190	254.254	255.62	255.126	255.190	255.254
Broadcast	254.63	254.127	254.191	254.255	255.63	255.127	255.191	255.255

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