HD Doctor Blog

If you need to remove sensitive data totally from your harddisk, simply deleting these files is not enough! Using advanced methods, it is even possible to recover data that’s been overwritten, unless it has been overwritten using carefully selected platterns!

Operating systems usually do not totally delete the file, but just mark the file as being ‘deleted’ so it can not be accessed when you view the contents of a directory. This means that you can not see the file anymore with normal tools, but specialized recovery tools can still access your data.

To prevent this from happening, you need to totally erase your files, using one of the specialized data removal tools you can find in this section. These…

The services listed in this section enable you to backup, store and/or share your files on the Internet for free.

4shared.com
1 Gigabyte of free space to share files.

DriveHQ
Free 1Gb of remote storage space including FTP access and file-sharing. The non-free plans range from 2 Gb for $ 2.99/month up to 20 Gigabytes for $19.99/Month

File Hamster
Free real-time backup and archiving of your files while you work, monitor specific files on your hard drive and automatically create incremental backups, etc.

FLASHspace
Remote storage space which presents itself as simply another disk-drive inside your Windows computer (no software needs to be installed).The 50 Mb package is free. The non-free packages start from $ 2 per month for 500…

A virtual disk is a program or driver which allows you to access a file (usually a disk-image file) as if it is an external drive.

VM Back
A virtual floppy drive for Windows

Free encrypted virtual drives
A listing of free disk encryption software and encrypted virtual drives.

XOR
Exclusive “Or”, a computer language function that generates parity in RAID systems; “this or that but not both

Usable storage capacity
Disk array capacity that is usable for data storage (vs. for mirroring or parity data). For example, under mirroring (RAID 1 and 0/1), usable storage remains a constant fifty percent (half of storage is always used for redundancy). This is in contrast to other RAID levels such as RAID 5, in which usable storage capacity is determined by the formula of “n-1″. “n” is the total number of disk drives and “1″ is the number of disks worth of capacity used for parity (redundancy) overhead. So, as the number of disks in the array grows, the usable storage capacity percentage increases in relation to parity (redundancy) information.

Write-Back Cache
A caching strategy whereby write operations result in a completion signal being sent to the host operating system as soon as the cache (not the disk drive) receives the data to be written. The target disk drive will receive the data at a more appropriate time in order to increase controller performance. An optional cache battery backup can be used to protect against data loss as a result of a power failure or system crash.

Write-Through Cache
A caching strategy whereby data is written to the SCSI drive before a completion status is returned to the host operating system. This caching strategy is considered more secure, since a power failure will be less likely to cause loss of…

Terminator
A part used to end a SCSI bus.

Termination
A method of matching transmission impedance of a bus to eliminate signal reflections from the physical ends of the bus.

Throughput
The number of I/O requests satisfied per unit of time (usually per second).

TPC-C, Tpm-C
The Transaction Processing Performance Council (TPC) is a standards organization that measures transaction throughput of systems. One of their benchmarks is Tpm-C, which reflects price and performance metrics. TPC-C reflects new order transaction rate, a benchmark for transaction speed. Mylex products have won consistently high TPC-C results.

Transfer Rate
The rate at which data moves between the host computer and storage, input, or output devices, usually expressed as a number of characters…