If I wanted to remotely monitor a computer room, data centre or any other kind of normally unmanned building, how would I do this? With such systems, could I be actively alerted of such occurences as fire, smoke, intruders etc?
From the Axis 207 upwards the capability is built into the camera to trigger an event based upon Video Motion Detection (VMD), and then to send an email with images attached.
You would probably choose to connect the cameras to a recording solution such as Icode's iCatcher Console software, to be sure that you were actually capturing and storing all incidents and events. This software can also email you with images. You would then be able to remote access the system and see live views.
You could also link the software to a web service which would send you a text message upon event detection.
Or even bolt-on Icode's Pocket Monitor application (just £15) and view live images on your phone.
What you want is not best done with any camera system alone. You will get to many false alarms and it will end up being useless, TRUST ME IVE BEEN THERE.
I use several cheap trendnet cameras coupled with go1984 NVR solution and Senturion Environmental Monitor to take care of all the things you wanted to cover plus a whole slew of other things. Senturion is also capable of supporting the cheap trendnet cameras, go figure, but if something messes up Senturion will call you if you want after oh i don't know the temperature hits 150F or someone opens the server room door. Sorry I know its a UK site but I am not to familiar with C.
Senturion is one of many whats called server room environmental monitoring systems. Its good for the price but there are many more out there and depending on what you require you may find another vendor to better suit your needs, I have catalogs that I bring to customers that are filled with things I have used in the past and been successful with but sometimes you run into a situation where it is time to do some more product research, its a part of this industry.