What Hardware is required?

Usually the IT department will install the equipment.

A Personal Computer is required with Internet access. A laptop with a wireless card could suffice.

A soundcard is required and a built in microphone and speaker may not have sufficient power to serve a large group, so an external speaker that is plugged in to a power source should have enough power boost to be heard by a large group. A sensitive microphone that can serve a group should be plugged in and situated in the center and toward the front of the room.
A wide angled camera should be plugged in and should have a view of the whole room. It will be helpful if it has a zoom and pan control since a fixed lens wide angle may show the room but not provide much clarity about who is speaking.