IP broadcasting anyone?

Question

Hi Folks,

I'm working on an application that will ping devices on our network and alert us when a device is no longer pingable.  I've have it where I can actually ping specific devices however it's very limited in the number of devices I can ping due to time constraints (I need to check every device every 3 minutes).  I just learned today about IP broadcasting which, on paper, sounds like a godsend to me.  Send me a list of all of the devices that available on the network?  Yes, please!  I can then easily compare it to what the database is looking for - that would be my perfect world.

So I've been scouring the 'net looking for example code for doing the broadcast and I can't seem to find a whole lot.  And on top of that I wonder if I can do it on my network.  Is that something that the network could be configured to prevent?  I could see where hackers would love it if they could get past a firewall and then just make a broadcast and get back all of the ip addresses on the subnet.  So besides the all important question of "does anyone have good working code snippets for doing this" I also need to know what I should be looking at to make sure it's even feasible on my network.  I don't have access to the network admin people - they're many miles away and just the question might raise some eyebrows so I would prefer a more technical way of determining this at the local level.

Thanx!