A FireWire hub is analogous to a USB hub; its primary purpose is to provide additional FireWire ports to which you can connect FireWire devices.
For more information on FireWire, see "FireWire," p. 626.
Because many Macs include only two FireWire ports (most mobile Macs have only one), and peripheral devices such as keyboards and monitors don't include additional ports, you are more limited in the number of FireWire devices you can attach to your Mac than you are with USB "out of the box."
If you use multiple FireWire storage devices, such as a hard drive, CD-RW, or other device that you will want to be connected at all times, you are probably going to need to add more FireWire ports to your system.
FireWire hubs work in a way that is quite similar to a USB hub, and you have similar parameters to choose from:
Number of available ports; most FireWire hubs include either three or six ports
Self-powered, bus-powered, or both
The process of choosing, installing, and using a FireWire hub is also analogous to the same tasks for a USB hub (see Figure 24.4). First, decide how many ports you need. Second, decide whether you need a more mobile hub that can take its power from the bus. Third, look for any special features you might need (there aren't many available, so this won't take much time).
Remember that one port will be used to connect the hub to the Mac or to another hub. Most of the time, you can connect one less device to a hub than the number of ports it offers. Because FireWire devices are also hot-swappable, you need only a dedicated port for those devices you want to be connected to your Mac at all times. As long as you have at least one available port for the devices you use only periodically, it isn't a big deal to connect and disconnect those devices.
Installing and using a FireWire hub is also as simple as installing and using a USB hub. Simply connect the hub to your Mac using a FireWire cable, connect its power supply (if applicable), and connect FireWire devices to the hub.
Some FireWire devices include multiple FireWire ports, so you can use them as hubs or to daisy chain other devices.
The FireWire cable you use depends on the device. Many devices use a FireWire cable with a standard FireWire connector on each end, but some devices, such as digital video cameras, have a uniquely shaped FireWire port. The specialized cable you need for such devices is usually included with the device.
You can chain both USB and FireWire hubs. This means that you can connect hubs of the same type to one another to continue to add devices to your system, up to the maximum number of devices supported by that interface.