There are different methods to connect multi-drive enclosures to a SATA controller card, each has it's advantages and disadvantages. The 3 most common connection interfaces.

Individual eSATA Connections:

With this method, you would have a separate eSATA output on the back of the enclosure for each drive that you have in the enclosure. For example, if you had a quad-bay SATA enclosure, you would have 4 eSATA connectors on the back of the enclosure. Like the Addonics ST6ESA Storage Tower - note that this device actually can accomodate 6 devices when utilising the Addonics RAID arrays.



Benefits: -Each drive gets a full 3.0Gb/s SATA connection (controller dependant & needs SATA 2 drives). Also not all of the drives need to go to the same controller or even the same computer.

Drawbacks: -Many connection points and cables and requires you to have enough eSATA ports available on the controller card (as many eSata ports as you have drives)

MultiLane:

With a multilane enclosure, often called "Infiniband", there is one heavy-duty connector that can support up to 4 SATA drives. The Addonics ST4SAML Storage Tower can be configured with optional hot-swap SATA caddies for added functionality.



Benefits: -1 Heavy-duty connector with screws that won't come dettached. Each drive gets a full 3.0Gb/s SATA Connection

Drawbacks: -Only supports up to 4 drives. Requires a Multilane enabled SATA interface card.

Port Multiplier:

A port multiplier is a piece of hardware that is inside the Addonics ST5X1PM Storage Tower and has one eSATA connection to the SATA controller, and then 5 SATA connections for each of  individual internal SATA drives. When you purchase an Addonics port multiplier Storage Tower, you can choose between two different types. The ST5X1PM which allows you to create RAID arrays using a port multiplier compatable SATA controller, or the Addonics ST5XHPM which is a hardware based RAID solution which will run on any eSATA controller, but needs to be initially configured with a port multiplier capable controller before use.



Benefits: Only one eSATA connection is necessary on the controller card. Up to 5 drives supported. You can connect more than one port multiplier enclosure to a SATA conroller for a large array of disks (Dependant on the number of eSATA ports on the controller. With four eSATA connections, you can connect up to 20 drives.)

Drawbacks: All drives must share a 3.0Gb/s eSATA connection. The SATA controller MUST be port multiplier compatible (Addonics highly recommended).