I have typically known 'flat network' to be a non-vlan network, typically a single /24. We have a new hire (security analyst) at my company and he asked the desktop support supervisor if he had "trouble getting your job done on this flat network". I'm a bit unsure how he means this, unless he is referring to it being a layer 2 domain as opposed to a routed site. Currently the site in question is multiple vlans, each in it's own /24 with the site as a /16. It's all L2, except for intervlan routing in the core.
Am I wrong in my usage of 'flat network', or am I missing something here?