A network backbone that consists of the backplane of a single switch, rather than multiple switches connected together. From the ports of the single switch, cables connect to the hubs of individual LAN segments.
Collapsed backbones are typically used for mid-sized LAN networks. The architecture is easier to manage, easier to keep secure and less costly as there are fewer networking devices.
However, a collapsed backbone architecture typically uses more cabling over longer distances and a failure in the central switch will cause the whole network to go offline.