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Product Features
3.1
SATA 6 Gb/s
SATA 6 Gb/s is the next generation interface for SATA hard drives. It adds to the functionality of the
SATA II interface with the following features:
Native Command Queuing (NCQ) — server feature for performance in random I/O transaction
environments. It aggregates many small random data transfers and allows the disk to reorder the
commands in a sequential order for faster access.
Improved Power Management— provides improved power management features including Host
Initiated SATA Power Management (HIPM) and Device Initiated SATA Power Management
(DIPM).
Staggered Spin-up — allows the system to control whether the drive will spin up immediately or
wait until the interface is fully ready before spinning up.
Asynchronous Signal Recovery (ASR) — robustness feature that improves signal recovery.
Enclosure Services — defines external enclosure management and support features.
Backplane Interconnect — defines how to lay out signal line traces in a backplane.
Auto-activate DMA — provides increased command efficiency through automated activation of
the DMA controller.
Device Configuration Overlay (DCO) — allows hiding of supported features via a SATA feature
mask.
3.2
Optional Self Encrypting Drive (SED)
Utilizing an AES 256 bit encryption engine for Crypto erase capability, WD supports both industry
standard commands of the Sanitize Feature Set and also the Security Feature Set which utilizes the
Secure Erase Unit (SEU) enhanced mode bit.
3.3
Time-Limited Error Recovery (TLER)
WD has delivered coordinated error management in the form of Time Limited Error Recovery
(TLER). TLER-capable hard drives will perform the normal error recovery and, after 7 seconds, issue
an error message to the RAID controller and defer the error recovery task until a later time. With
coordinated error handling, the hard drive is not dropped from the RAID array, thereby avoiding the
entire RAID recovery, replacement, rebuild, and return experience.
The error handling is further coordinated between the TLER-capable hard drive and the RAID card.
The TLER capable drive will respond without waiting on the error to be resolved. RAID cards are very
capable of handling this with a combination of parity protection and journaling. The RAID card flags
the error in the error log and proceeds to deliver data using parity protection until the drive retries its
own error recovery and corrects the error. This is quite similar to error management proven in SCSI-
RAID for many years. Though TLER is designed for RAID environments, it is fully compatible with
and will not be detrimental when used in non-RAID environments.
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SED drives may require TCG-compliant host or controller support. SED drives may not be available in all countries
18
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RELEASED 8/13/13
EX800M
2679-771339-A05
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