A little over a year ago a network engineer came in to setup a captive webportal for out BYOD WiFi. Now this is nothing to do with BYOD directly, that's just what he was doing. He asked me if I'd like him to check the health of out network. I agreed to this and he plugged in his laptop into our network and fired up an application that I now know was WireShark.
About 15 minutes later, he pronounced out network to be 80% dead. This troubled me somewhat and the engineer spent the next hour or so explaining all that was wrong about our network. In brief, we had a 'flat' network - so all devices were on the same IP address range 192.168.x.x. This I leant was bad as when one devices wanted some information from another device, it sent the request to every devices on our network - some 600 odd devices. This is broadcast traffic and 80% of out network traffic was this.
The solution looked simple on a piece of paper that he wrote on. Segment the network into several different s…