127 USB devices are supported by one host controller.
127
Four computers and two phone devices can be connected with that.
4
One. SATA interfaces are USUALLY only one device at a time. It is possible, if the controller supports it, to use a port multiplier which allows you to use four devices off one port .
2
128
2
2 devices
I read by 2012, 17 billion devices will be connected to the internet
In a plain SCSI (Small Computer System Interface) chain, up to 8 devices can be connected, including the SCSI host adapter. This means there are 7 additional devices that can be connected to the chain. SCSI IDs range from 0 to 7, with each device needing a unique ID for proper communication.
16 devices can be connected
The number of devices you can link to a router will depend on the specific router,typically 4 devices can be connected.