How many total host addresses are unused across all four subnets with the network address 192.168.99.0 and a subnet mask of 255.255.255.192?

To determine the total unused host addresses across all four subnets with the network address 192.168.99.0 and a subnet mask of 255.255.255.192, we need to start by analyzing the subnet mask.

The subnet mask 255.255.255.192 corresponds to a /26 prefix, which means the network is divided into segments that each have 64 addresses (since 2^(32-26) = 64). Out of these 64 addresses in each subnet, two addresses are reserved: one for the network address and one for the broadcast address. This means that each subnet has 64 - 2 = 62 usable host addresses.

Given that there are four subnets in this case, we can calculate the total number of usable host addresses across the subnets:

62 usable addresses per subnet * 4 subnets = 248 usable host addresses.

To find the total host addresses available across all four subnets, we take the total address count (64 per subnet) and multiply it by the number of subnets:

64 addresses per subnet * 4 subnets = 256 total addresses.

Now, to find out how many total host addresses are unused, we subtract the number of usable addresses