Tamper-proof security hardware resists or reports interference. Housings may be reinforced, cabling concealed and fasteners made hard to reach, while switches and accelerometers detect a case being opened, moved or sprayed, and the system raises an alert when they do.
No housing is immune to a determined attacker with the right tool. The realistic goal is to make interference slow and noisy, so it costs time and leaves a record.
Resistance and detection differ
Resistance slows access to the device, while detection reports that someone tried. A camera with an impact-resistant dome but no tamper switch tells nobody that it was struck.
Protecting the path, not only the box
Conduit, locked enclosures and a recorder in a secure room matter as much as the camera. The weakest part of most installations is the exposed cable and the unattended network closet at the end of a hall.