Using locking racks is the best method to secure network equipment physically as it helps prevent unauthorized access to the equipment itself. While using asset tags helps track assets and monitor movement, it does not actively restrict physical access to the equipment. Surveillance cameras act as a deterrent and provide a means of investigation after an incident but do not prevent equipment access. Having a secure site perimeter is essential, but it does not replace the need for securing individual components like network equipment within the data center.