If you are borrowing 2 bits, then the subnet masks will look like:
255.192.0.0 Class A
255.255.192.0 Class B
255.255.255.192 Class C
To find the range of hosts for the IP address 172.26.64.0 with a subnet mask of 255.255.192.0, first, determine the subnet mask in CIDR notation, which is /18 (since 255.255.192.0 corresponds to 18 bits). The network address is 172.26.64.0, and the broadcast address is 172.26.127.255. Therefore, the usable host range is from 172.26.64.1 to 172.26.127.254.
Same as subnetting any other class, or a classless network. From the bits originally reserved for the host (16 bits, in the case of a class B address), you "borrow" some bits, that is, you use them to specify the subnet. The remaining bits specify an individual host within a subnet.
255.0.0.0
Since a subnet mask is used to separate the network id from the host id, any 1 bits indicate the network portion and the 0 bits indicate host portion. As an example, in the subnet mask: 255.255.0.0 This indicates the first two octets are used for the network, and the last two octets (ipV4) are used for host portion of an address.
You must extract the first 8 bits of the host address (since the subnet mask has the first 8 bits equal to 1), and set all others to zero. The answer in this case is 86.0.0.0.You must extract the first 8 bits of the host address (since the subnet mask has the first 8 bits equal to 1), and set all others to zero. The answer in this case is 86.0.0.0.You must extract the first 8 bits of the host address (since the subnet mask has the first 8 bits equal to 1), and set all others to zero. The answer in this case is 86.0.0.0.You must extract the first 8 bits of the host address (since the subnet mask has the first 8 bits equal to 1), and set all others to zero. The answer in this case is 86.0.0.0.
In IPv4, there are a total of 32 bits in an IP address. The number of network and host bits varies depending on the subnet mask used. Typically, the first part of the bits represents the network portion, while the remaining bits represent the host portion. For example, in a common subnet mask of 255.255.255.0 (or /24), there are 24 bits for the network and 8 bits for hosts.
There are 16 bits available; it is up to you how many of those bits you reserve for the subnet, and how many for the individual hosts within each subnet.
The subnet mask for a /26 subnet indicates that the first 26 bits are used for the network portion, leaving 6 bits for the host portion. In this case, the subnet 172.168.2.0/26 can accommodate 2^6 = 64 addresses, but only 62 are usable for hosts (subtracting the network and broadcast addresses). Thus, there are 26 bits designated for the network and 6 bits for hosts within this subnet.
Subnet Mask
To create 6 subnets from the IP address 172.16.0.0, you need to determine how many bits to borrow from the host portion of the address. Since 2^3 = 8, borrowing 3 bits allows for 8 subnets, which is sufficient for your requirement of 6. This results in a subnet mask of 255.255.248.0 (or /21), providing each subnet with 2046 usable host addresses. The subnets would range from 172.16.0.0/21 to 172.16.7.0/21.
This assumes you know how to subnet. On a network with 190.254.0.0 as a host address and using 11 bits for the subnet mask. The network address is 190.224.0.0 and the end of the range is 190.255.255.224. The address you show is within this range so cannot be the network address. If you don't know how to work this out manually use a subnet calculator such as the one on this URL: http://www.boson.com/FreeUtilities.html
A subnet with a prefix of /100 indicates that the first 100 bits of the IP address are fixed for the network portion. However, since IPv4 addresses are only 32 bits long, a subnet mask of /100 is not valid in this context. In IPv6, which allows for longer prefixes, a /100 subnet would have 100 bits dedicated to the network, leaving 28 bits for host addresses.