By implementing a hard zone based on World Wide Names (WWNs), the administrator can strictly control which physical devices (in this case, the development team's servers) can communicate with each other and access the testing databases. Hard zoning is enforced by the SAN hardware itself, thus preventing any communication with devices (such as production databases) that are not included in the zone, whereas a soft zone could be susceptible to device spoofing because it's enforced through software.