This is good to know when you need to identify, map out, and troubleshoot hub and device connectivity. Most freestanding external hubs provide 4 or 7 ports. Devices - Devices connect to hubs and provide expanded functionality to the computer. Devices connect to the host and transfer data at either the 1.5 or the 12 Mbps connection speed.
Devices can only connect to hubs.
Devices cannot connect directly to devices, but looks can be deceiving, since some devices are combined with hubs in the same physical case. As mentioned earlier in this training, USB networks are tiered-star hubs. Most people shouldn't have a problem with this limit, although devices can add up faster than expected. For example, a keyboard with a built-in trackball counts as two devices. This can be tricky to track sometimes, since hubs can be hidden in CPU cases, displays, keyboards, etc.