The motherboard of a GarrettCom Magnum 6K Series managed switch with conformal coating and special heat sinks is designed to support convection cooling. Both features are important when installing switches in dusty, corrosive, or damp environments. Source: GarrettCom Inc.
Jim makes an important point about the lack of interchangeability between commercial routers and switches and industrial ones. The same thing goes for PCs--perhaps even more so. This article talks about hardening mainly in terms of physical hardening -- resistance to temperature extremes and use of conformal coating as protection. The other aspect is that commerical PCs and network gear have subtle differences from model to model, or even in the same generation. This makes the kind of swapping out that's done in the commercial world much more difficult to get away with in industrial settings, where the gear has to work and be up 100%, without having to constantly send in an IT person to tweak settings and diagnose problems.
The switch may be industrial, but as I commented in the Ethernet in the car article, the connectors are NOT. RJ45 does not belong in industrial settings; it's time for a new robust connector. M12 Code D might be it. Maybe M8 for higher connector densities?
There are a number of vendors out there that make what they might call industrial strength Ethernet devices. There is still room for improvement beyond simple temperature and vibration specs. I would like to see something with an IP-67 rating, for instance, so you don't need to enclose everything.
(TJ, I just added a comment to the auto article as well adressing the plastic tab connector concern).