Subnet Cheat Sheet – 24 Subnet Mask, 30, 26, 27, 29, and other IP Address CIDR Network References
| CIDR | Subnet mask | # of IP addresses |
|---|---|---|
| /17 | 255.255.128.0 | 32,768 |
| /16 | 255.255.0.0 | 65,536 |
| /15 | 255.254.0.0 | 131,072 |
| /14 | 255.252.0.0 | 262,144 |
How many subnets are in Class A?
The reason you would use this with a Class A mask is because it can give you up to 4,194,304 subnets with two hosts each.
How big is a 14 subnet?
IPv6 Subnet Calculator
| Prefix size | Network mask | Usable hosts per subnet |
|---|---|---|
| /14 | 255.252.0.0 | 262,142 |
| /15 | 255.254.0.0 | 131,070 |
| Class B | ||
| /16 | 255.255.0.0 | 65,534 |
What would the subnet mask be for a class B network that has 14 subnets?
255.255.240.0
Subnetting a Class B network address
| Mask | Binary | Subnets |
|---|---|---|
| 255.255.240.0 | 11110000.00000000 | 14 |
| 255.255.248.0 | 11111000.00000000 | 30 |
| 255.255.252.0 | 11111100.00000000 | 62 |
| 255.255.254.0 | 11111110.00000000 | 126 |
What is the subnet mask of Class A?
255.0.0.0
Class A networks use a default subnet mask of 255.0. 0.0 and have 0-127 as their first octet.
What is subnet mask of Class B?
Class B networks use a default subnet mask of 255.255. 0.0 and have 128-191 as their first octet. The address 172.16. 52.63 is a class B address.
How do you calculate subnet mask?
Subnets, hosts and broadcast addresses per subnet: To find the valid subnets for this specific subnet mask you have to subtract 248 from the value 256 (256-248=8), which is the first available subnet address.
How do I calculate subnet mask?
The number of subnets is found by counting the number of bits by which the initial mask was extended, also known as the subnet bits. Our initial address allocation was 192.168. 0.0 with a mask of 255.255. 0.0.
How does subnet mask work?
A subnet mask is a 32-bit number created by setting host bits to all 0s and setting network bits to all 1s. In this way, the subnet mask separates the IP address into the network and host addresses. The “255” address is always assigned to a broadcast address, and the “0” address is always assigned to a network address.
How do I calculate my subnet mask?
What is the default subnet mask for Class A subnet?
The mask. Class A subnet masks must start with 255.0.0.0 at a minimum, because the whole first octet of an IP address (the IP address describes the specific location on the network) is used to define the network portion (the network portion describes the “street” that IP addresses are located on).
How do you find the subnet address of a network?
Here are some tips for finding the answers: Valid subnet address: To figure out the valid subnet address, simply subtract the subnet mask from 256. For example, if you had a Class A mask of 255.240.0.0, the equation would be 256-240=16. The number 16 is the first subnet and also your block size.
How can I create smaller networks (subnetworks) out of a network ID?
If you wanted to create smaller networks (subnetworks) out of a Class A network ID, you’d borrow bits from the host portion of the mask. The more bits you borrow, the more subnets you can have, but this means fewer hosts per subnet.
How many hosts and subnets are there in table a?
Table A Mask Prefix Subnets Hosts 255.0.0.0 (/8) 1 network with 16,777,214 hosts 255.128.0.0 (/9) 2 subnets with 8,388,606 hosts each 255.192.0.0 (/10) 4 subnets with 4,194,302 hosts each 255.224.0.0 (/11) 8 subnets with 2,097,150 hosts each
