The default gateway must be an IP address on the same network as the workstation. Given the subnet mask of 255.255.255.0, any IP address in the range of 192.168.1.1 to 192.168.1.254 would be on the same subnet as the workstation. Typically, the default gateway is the first or last IP address in the subnet. However, without knowing the exact configuration of the network, any address in this range could be the default gateway. The administrator must choose an IP address that is configured on one of the network's routers and operates as a gateway to external networks.