Segmentation is recommended for network design because it enforces physical separation,
where test code could bring down the whole corporate network, which would cause
far more damage and chaos than just crashing the testing LAN if there was no
physical separation. Example scenario would be: If the testing network is
completely isolated, it is not possible for a piece of test code to accidentally
affect the management LAN or back-end processing LAN. It might affect the whole
testing network, but it will be isolated to that one segment.
