eSATA AND SATA?

Question

What is the diffrence between eSATA and just SATA? is there any differnce?

wow aresharmony ur answer was so long and complex its to bad i could really understand what u were saying i hope i didnt waste ur time!

Answer 1

Standardized in mid-2004, eSATA defined separate cables, connectors, and revised electrical requirements for external applications:

Minimum transmit potential increased: Range is 500–600 mV instead of 400–600 mV.
Minimum receive potential decreased: Range is 240–600 mV instead of 325–600 mV.
Identical protocol and logical signaling (link/transport-layer and above), allowing native SATA devices to be deployed in external enclosures with minimal modification
Maximum cable length of 2 m (USB and FireWire allow longer distances.)
Aimed at the consumer market, eSATA enters an external storage market already served by the USB and FireWire interfaces. Most external hard disk drive cases with FireWire or USB interfaces use either PATA or SATA drives and "bridges" to translate between the drives' interfaces and the enclosures' external ports, and this bridging incurs some inefficiency. In the case of USB 2.0, protocol overhead limits the maximum effective bandwidth to a fraction of USB's physical signalling rate. With modern hard disk drives, USB's transfer rate is a bottleneck. FireWire, with its isochronous transfer mode, is more efficient, such that even in its slower variant, FireWire 400 (IEEE 1394a), the effective transfer rate is significantly faster than that of USB 2.0, but this can still be a bottleneck for fast drives or RAIDs. Some single disks can transfer well over 70 MB/s during real use, well in excess of USB 2.0's or the older FireWire 400's abilities. Finally, some low-level drive features, such as S.M.A.R.T., are not usable through USB or FireWire bridging. eSATA does not suffer from these issues.

eSATA will likely co-exist alongside USB 2.0 and FireWire storage for several reasons. The ubiquity of USB ports on all mass-market computers, and FireWire ports on many consumer electronic appliances, guarantee a large market for USB and FireWire storage. For small form-factor devices (such as external 2.5" disks), a PC-hosted USB or FireWire link supplies sufficient power to operate the device. Where a PC-hosted port is concerned, eSATA connectors cannot supply power, and would therefore be more cumbersome to use.

As of 2007, few computer motherboards have eSATA connectors. Non-equipped desktops can be upgraded with the installation of an eSATA host bus adapter (HBA), while notebooks can be upgraded with Cardbus or ExpressCard versions of an eSATA HBA. Also available are passive eSATA-to-SATA bracket/cable-adapters. With passive-adapters, the maximum cable length is reduced to 1 meter, due to the absence of compliant eSATA signal levels. Full SATA speed for external disks (115 MB/s) have been measured with external RAID enclosures.

eSATA is likely to be ignored by the enterprise and server market, which has already standardized on the separately-developed Serial Attached SCSI (SAS) interface, which has extra features for remote management, link redundancy, and link monitoring.

Note: Prior to the final eSATA specification, there were a number of products designed for external connections of SATA drives. Some of these use the internal SATA connector or even connectors designed for other interface specifications, such as FireWire. These products are not eSATA compliant. The final eSATA specification features a specific connector designed for rough manipulation. It's similar to the regular SATA connector, but with reinforcements in both the male and female sides, inspired by the USB connector. It's harder to unplug and can withstand a cable being yanked or wiggled. On a SATA connector, this kind of action will break the male side of the connection (the hard drive or host adapter), rendering the device unusable. With an eSATA connector, considerably more force is needed to damage the connector, and even in this situation, only the female side (the cable itself) will break, possibly leaving the male usable.[citation needed]

In computer hardware, Serial ATA (SATA, [ˈseɪ.tə] or IPA: [ˈsæ.tə]) is a computer bus technology primarily designed for transfer of data to and from hard disks and optical drives. It was designed as a successor to the legacy Advanced Technology Attachment standard (ATA), and is expected to eventually replace the older technology (retroactively renamed Parallel ATA or PATA). Serial ATA adapters and devices communicate over a high-speed serial link.

eSATA compared to other buses
eSATA SATA 300 PATA 133 FireWire 800 FireWire 400 USB 2.0 Ultra-320 SCSI
Speed (Mbit/s) 2400 2400 1064 786 400 480 (burst) 2560
Max. cable length (m) 2 1 0.46 4.5 (16 cables can be
daisy chained up to 72 m) 4.5 (16 cables can be
daisy chained up to 72 m) 5 (USB hubs can be
daisy chained up to 25 m) 12
Power provided No No No Yes (12-25 V, 15 W) Yes (12-25 V, 15 W) Yes (5 V, 2.5 W) No
Devices per Channel 1 (15 with port multiplier) 1 per line 2 63 63 127 16

Unlike PATA, both SATA and eSATA are designed to support hot-plugging. However, this feature requires proper support at the host, device (drive), and operating-system level. In general, all SATA/devices (drives) support hot-plugging (due to the requirements on the device-side), but requisite support is less common on SATA host adapters.

Answer 2

the only problem i see with that is the internal sata ports may not have the same options as an external sata so it might not have a hot swappable option

Answer 3

Here's more from a motherboard maker:
http://www.asrock.com/news/eSATAII.asp

Answer 4

can u please tell me which modulation scheme used in eSATA rev3? and what is analog bandwidth for that I have a assignment to make on this topic.thank you