SPTD

SPTD (SCSI Pass Through Direct) is an access layer that provides direct control of devices, a method different from the SCSI Pass Through Interface that is included in the Windows OS by default.
Courtesy of the included direct device control, SPTD eliminates the scenarios in which its performance would be compromised by malicious third-party filter drivers or rootkit applications.
In fact, the main idea behind SPTDs development, for both the organizations and the applications that currently take advantage of what it has to offer, was to improve and secure the access to storage devices. It also offers data management through storage virtualization.
SCSI Pass Through Direct is not different from other access layers that are being used in other applications, as it too offers access to storage devices. However, SPTD includes a series of additional features that are meant to make it a unique interface.
One thing that users should keep in mind is the fact that there are applications that integrate SPTD. The access layer is bundled with these programs and they will not work without it.
However, SPTD wont be removed from the computer when the application that integrates it is uninstalled, something that usually happens when it comes to access layers.
Provided that there are other applications on the machine that take advantage of SPTD, they will not be disrupted by the uninstallation. Additionally, users no longer need to reboot the computer when installing an app that is bundled with the same SPTD version that is already loaded on the system.
As an additional safety measure, newer versions of SPTD automatically create a System Restore point before the access layer is installed (as long as the System Restore functionality has been previously enabled on the PC).
SCSI Pass Through Direct (SPTD) is being used by applications such as Alcohol 120% and Daemon Tools, but it is incompatible with kernel-mode debugging.