How many usable IP addresses are available in a network with a subnet mask of 255.255.255.240?

How many usable IP addresses are available in a network with a subnet mask of 255.255.255.240?

• A. 12
• B. 14
• C. 16
• D. 18

Answer: (B)

To determine the number of usable IP addresses available in a network with a subnet mask of 255.255.255.240, it's important to first understand the subnetting involved. A subnet mask of 255.255.255.240 is equivalent to a prefix length of /28. This means that 28 bits are used for the network part of the address, leaving 4 bits for the host addresses. The number of possible addresses that can be assigned to hosts is calculated using the formula 2^n, where n is the number of bits available for hosts. In this case, n is 4 (since 32 total bits - 28 bits for the network = 4 bits for hosts). Calculating this gives: 2^4 = 16 total IP addresses. However, in any subnet, two addresses are reserved: one for the network address (the first address in the range) and one for the broadcast address (the last address in the range). Therefore, to find the number of usable IP addresses, we subtract these two addresses from the total: 16 total addresses - 2 reserved addresses = 14 usable addresses. This is why the correct answer is 14. Understanding subnetting and how to calculate the number of

To determine the number of usable IP addresses available in a network with a subnet mask of 255.255.255.240, it's important to first understand the subnetting involved.

A subnet mask of 255.255.255.240 is equivalent to a prefix length of /28. This means that 28 bits are used for the network part of the address, leaving 4 bits for the host addresses. The number of possible addresses that can be assigned to hosts is calculated using the formula 2^n, where n is the number of bits available for hosts. In this case, n is 4 (since 32 total bits - 28 bits for the network = 4 bits for hosts).

Calculating this gives:

2^4 = 16 total IP addresses.

However, in any subnet, two addresses are reserved: one for the network address (the first address in the range) and one for the broadcast address (the last address in the range). Therefore, to find the number of usable IP addresses, we subtract these two addresses from the total:

16 total addresses - 2 reserved addresses = 14 usable addresses.

This is why the correct answer is 14. Understanding subnetting and how to calculate the number of