ESATA - what is it? Types and types of eSATA

Today the eSATA port has long ceased to be something really new and exotic. However, in this case, not all users are familiar with it and do not quite clearly imagine what advantages and disadvantages are given by this standard in everyday work with a computer.

A bit about eSATA

Of course, beginners will be first of all interested in learning eSATA - what it is and what it is eaten with. If to try to answer easier, then this serial port standard lies in speed and ease of use somewhere between the USB2.0 standards and the traditional SATA. The term itself has an abbreviation for External Serial ATA, that is, a port that uses advanced technologies for serial data exchange and has the ability to hot-swap both hard drives and other devices connected to the computer on the fly.

Despite the fact that eSATA-connection appeared in 2004, today often users prefer more traditional technologies - USB and SATA.

Advantages

Of course, the eSATA standard would not have been distributed, if it had not had its objective advantages. And these include:

• The possibility of extending the cable for data transmission up to 2 meters without the danger of signal distortion;
• ESATA signal compatibility with SATA;
• Accelerated data transfer compared to USB2.0;
• Cheapness in production allows to equip chipsets with several eSATA ports and to use this connector in many devices. For example, there is an eSATA external hard drive and even a USB flash drive;
• Hard disks can be combined into RAID arrays;
• It is possible to replace hard disks on the move, which is unthinkable provided the traditional SATA interface is used.

As you can see, the advantages of this interface are abound, at least in comparison with such common and usual standards as USB2.0 and SATA.

disadvantages

Answering the question, eSATA - what it is, you can not ignore the disadvantages of this type of connection. Despite the fact that this type of interface was launched in 2004, not all devices are equipped with ports of this standard, and so far its use is complicated by some inconveniences:

• Physical incompatibility of eSATA and SATA ports;
• The speed of data exchange is still somewhat lower than that of SATA. Numerous synthetic tests have confirmed this;
• The length of the cable is limited to two meters, which is less than in the case of USB;
• ESATA hard drive will require additional power via USB and 1394 or via a standard outlet (in newer models of external devices such a need often disappears);
• ESATA and SATA apply different signal levels;
• ESATA organization sometimes requires a special controller on the motherboard;
• So far, not many devices have been released that would support this standard.

As for the data transfer rate itself, eSATA outperforms the USB 2.0 standard in this respect, but it is inferior to the modern USB 3.0. Probably, what exactly is connected with this is the fact that eSATA connectors are not popular today: after all, it's easier to work with USB, and the speed in version 3.0 is higher.

Types of eSATA

Strangely enough, this interface has its own variants. However, there are not so many of them. Or rather, only two:

1. Actually eSATA, about the features of which was mentioned above.
2. ESATAp is a distinctive feature of this type of port in that it became possible to make the device powered directly through the eSATA cable, SATA also required to supply power through an external source without fail. Postfix p stands for power.

It would seem that with the advent of such a standard as eSATAp, all problems were solved, and this port is ready to become self-sufficient. But then USB 3.0 arrived, and eSATAp could not compete with it.

And plus 12 volts

However, you can connect any USB device to the eSATA port. Interfaces allow you to do this. At the same time, there will be a simultaneous make-up of the device and data transfer to both ends.

The main problem in this case is that some models of hard drives require not only standard 5 volts for make-up, but as many as 12. But in laptops such a powerful power source is not provided. That is why an improved version of eSATAp was developed, which provides for additional power contacts in the connector. The interface was unofficially called eSATAdp, that is dual power.

If there is no eSATA

Not often, but sometimes you need to bring an eSATA device with only a SATA port on the motherboard. For example, if you need to connect an external eSATA to a device.

You can do this, but this requires a passive extension cable that connects directly to the SATA on the motherboard. If we are talking about a laptop or a netbook, then this connection is possible through the PC Card adapters, and also through the Express Card. But in this case the maximum length of the cable will be limited to just one meter, which is not always convenient.

External devices with eSATA support

At one time, before the advent of USB 3.0, the eSATA interface was expected to have a bright future. External disk eSATA can be found on sale now. After all, USB 3.0 has not yet managed to oust its predecessor USB 2.0 everywhere.

And since the eSATA standard is designed primarily for fast data exchange, it is logical that the lion's share of the market for external devices that support this interface, are all kinds of drives. These are external hard drives and flash drives. But you can also find on sale also printers and scanners, which use this type of connection.

Unfortunately, some confusion associated with the presence of a small but a variety of SATA interfaces, eSATA, eSATAp, and eSATAdp, has led consumers to be confused with port and cable compatibility. And even the eSATA adapter does not always help to solve this problem, especially if the difficulties are not only related to compatibility, but also the need to carry out additional recharge (the same 12 volts). In addition, the eSATAdp standard has not yet been standardized.

While only remains to carefully monitor the compatibility of cables, so as not to confuse the cable eSATA, SATA and others. And hope that either all this is finally standardized, or a variety of SATA ports will be replaced by some more versatile port.

Why not FireWire or USB?

Of course, the answer to the question about eSATA - what it is, can not be considered complete without an attempt to analyze the opportunities on the part of competitors. In this case, FireWire and USB.

And the reasons why eSATA has not been replaced by them so far, three:

1. To organize data exchange through these two ports, you need to convert the PATA or SATA protocols to USB or the same FireWire. However, the bandwidth has significant limitations. This was not very noticeable in the old days, however, with the appearance of solid-state storage devices with volumes from 500 GB, which today did not surprise anyone, such a threshold became very noticeable.
2. The second reason is that even in the case of FireWire, there is a limitation on the data transfer speed of 400 Mbps, since the FireWire controllers function according to the IEEE 1394A standard . Here such a limitation is evident not so much with the use of large hard disks, how many high-speed, as well as large-scale RAID arrays, which, naturally, require very considerable speeds.
3. Finally, drives based on FireWire and USB do not have access to some low-level features. For example, to the function SMART At the same time, eSATA is spared this disadvantage.

Although competitive interfaces are very popular among ordinary users because of their convenience, however, in some cases, there is no way to do without an eSATA interface. So, if a user needs a high speed of information transfer of a large volume, this standard will be an ideal solution for this kind of tasks. Unfortunately, its implementation involves some technical difficulties, but with additional power, for example, using an external unit, this will not be a problem.

ESATA Outlook

While it is difficult to say anything with a 100% guarantee regarding the future of this interface. But without trying to predict when answering the question about eSATA - what it is, you can not do either.

While there are devices on the market that support working with ports such as USB 2.0, USB 3.0, and the aforementioned FireWire, the future of eSATA is uncertain. On the one hand, manufacturers are not in a hurry to actively use this port in all their devices, and on the other hand they still manufacture drives with such an interface, but they do not forget about USB 3.0 either.

ESATA looks good if you want, for example, to connect large storage devices or handle multimedia content as HD. Also this interface will help everyone who wants to have their own RAID array at home.

But many users will prefer to use in their daily work and a slower, but such a simple and intuitive interface, like USB 2.0. After all, most of them do not need to work with fast and capacious drives, in addition, often users are deterred by the need for additional powering the device with an eSATA interface. They are ready to put up with some restrictions on speed for the sake of convenience. But in some cases it is impossible to do without it.

So, we should not expect the eSATA interface to influence the market in the future, but it will not give up quickly either, because the demand for it still exists.

Many experts argue that this standard will survive until the spread of a more modern new standard, or eventually eventually take over USB 3.0. However, as long as this does not happen, you can safely purchase drives that operate on the basis of eSATA.