An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 192.168.0.0 255.255.254.0. What wildcard mask would the administrator use in the OSPF network statement?
- 0.0.15.255
- 0.0.3.255
- 0.0.1.255
- 0.0.7.255
| Explanation & Hint:
A wildcard mask is the inverse of a subnet mask. For the subnet mask 255.255.254.0, the binary representation is: 11111111.11111111.11111110.00000000Inverting this binary representation gives us the wildcard mask: 00000000.00000000.00000001.11111111This corresponds to the decimal wildcard mask: 0.0.1.255Therefore, the administrator would use a wildcard mask of 0.0.1.255 in the OSPF network statement to advertise the network 192.168.0.0 with a subnet mask of 255.255.254.0. |