If configuring an OSPF router to advertise the network 192.168.0.0 255.255.254.0, what wildcard mask is used?

To determine the correct wildcard mask for the OSPF router advertising the network 192.168.0.0 with a subnet mask of 255.255.254.0, it's important to understand how wildcard masks work in relation to standard subnet masks.

A subnet mask identifies the network and host portions of an IP address. In this case, the subnet mask 255.255.254.0 signifies that the first 23 bits are the network part (255.255.254, which is 11111111.11111111.11111110.00000000 in binary) and the remaining bits are used for host addresses.

The wildcard mask is essentially the inverse of the subnet mask. To calculate the wildcard mask, you subtract each octet of the subnet mask from 255. For 255.255.254.0, the calculation goes as follows:

• First octet: 255 - 255 = 0

• Second octet: 255 - 255 = 0

• Third octet: 255 - 254 = 1

• Fourth octet: 255 - 0 = 255

Putting that together, the wildcard mask becomes 0.0.1.255.