Port multipliers are devices that allow a single Serial ATA port to communicate with multiple drives. The port multiplier is transparent to the drives, but the host is aware that it is communicating with multiple drives. Port multipliers typically reside on an enclosure’s backplane and support all standard SATA drives.
Typically, Serial ATA (SATA) connectivity consists of a single drive connected to a single controller port via a single cable. The maximum number of drives in an array is predicated on the controller’s port count. The SATA Port Multiplier (SATA PM) permits a change to that point-to-point relationship via port multiplication technology. Port multipliers allow easy, cost-effective storage expansion and enable the aggregation of the performance of multiple drives as well.