With devices like external hard drives offering storage capacities, which are greater than a terabyte, it is hard to imagine that once people used floppies, with storage capacities of a mere 64 MB.
When it comes to connecting secondary data storage devices, the most popular computer bus options are USB (Universal Serial Bus) and FireWire. However, very few people are aware of the third option, which is eSATA (External Serial Advanced Technology Attachment).
What is eSATA?
External Serial Advanced Technology Attachment (eSATA), is a type of interface, used for connecting SATA based devices. It is actually the bus interface for internal hard drives and a successor of the ATA technology.
It provides a serial architecture for data transfer, with narrow but long connecting cables. The technology is a modification of SATA, to connect storage devices like external hard drives.
Why Opt For it?
One reason why one would go for these drives, instead of USB 2.0 or FireWire 400 is the phenomenal data transfer speeds they offer. eSATA hard drives are connected to your computer's high performance serial ATA bus through a direct channel. So, data transfer towards and away from such a drive, is comparable to data transfer rates of internal hard drives.
Unlike a USB device, data transferred through these drives doesn't have to pass through a USB channel, but uses a data transfer highway, which is the internal hard drive's bus. So, data transfer speeds through an eSATA drive can reach as much as 6GB/sec. That is why, an eSATA based drive can hold and transfer large amounts of data, at phenomenal speeds.
With the introduction of USB 3.0 and 3.1, this speed has exceeded, but problem with USB or FireWire is that their data has to first pass through external interfaces. If one needs to store large video files, whose transfer can be time-consuming on USB and FireWire based devices, eSATA is a better option.
External Hard Drive Enclosure
If you have an unused internal SATA hard drive, it can be converted into an external storage device, by using an enclosure. One drawback of using such enclosed eSATA drives is that they need power through an external cable, as they cannot draw power from the port.
The problem with using these devices is that most laptop computers and desktops do not have an eSATA port as yet. A separate hardware for connecting these devices needs to be purchased, which adds to the overall cost of the drives, which is already quite high, compared to USB 2.0.
People connecting these external devices are often hit with messages like 'external hard drive not recognized'' or 'drive not detected'', due to driver compatibility issues and other related problems. However, if one follows the installation instructions properly, there are generally no problems.
Opt for eSATA drives, if you need really high data transfer speeds. These devices come in handy, when you need speedy data transmission to transfer big video files. If data transfer speed is not an issue for you, USB and FireWire devices are good and cheaper too. Look at devices that offer the best trade off, between storage space, transfer speeds and cost.