Question

You have an interface on a router with the IP address of [IP Address]. Including the router interface, how many hosts can have IP addresses on the LAN attached to the router interface?

1. 64
2. 126
3. 250
4. 62
5. 256
6. 252
7. 254

Answer 1

Using the formula 2^(32 - subnet bits) - 2, one can calculate the number of usable host IP addresses on a LAN attached to a router interface once the subnet mask is known. Therefore, the correct option is 4. 62

Step-by-step explanation:

When determining the number of hosts that can be assigned IP addresses on a local area network (LAN) attached to a router interface, the subnet mask associated with the IP address is required. To calculate the number of available hosts on a network, you would use the formula 2(32 - subnet bits) - 2, where the '-2' accounts for the network and broadcast addresses which cannot be assigned to hosts. For example, a subnet with a /26 mask (which has 26 bits for the network portion) would have 2(32-26) - 2 = 64 - 2 = 62 usable IP addresses for hosts. This assumes the typical practice of reserving the first and last address in the subnet for network and broadcast addresses respectively.