A near infinite variety of types of devices are possible, but certain interfaces have limits on what can be connected:
- USB - 128 devices maximum (including hubs)
- Firewire - 63 devices maximum (including hubs)
- Thunderbolt - 6 devices maximum
- SCSI - 7 devices maximum
- MIL-STD-1553 - 30 devices maximum
- Fibre Channel - about 16777216 devices maximum
- RS-232 serial - 1 device maximum
- etc.
