Datasheet

1060
Do Not Forget about Data Protection
by writing the data at the same time to two different disks, essentially
taking less time to read or write to the file. Note that the data is split
between both drives, and there is no duplication — which means that
this is not really a redundant solution.
✦ RAID Level 1: Also known as a mirrored volume in Windows. A mirrored
volume duplicates the data stored on one disk to another disk. If one
disk fails, the other disk has a copy of the data.
✦ RAID Level 5: Also known as a RAID 5 volume in Windows. A RAID 5
volume requires a minimum of three drives and writes to all drives in
the solution like a striped volume. A RAID 5 volume is different than a
striped volume in the sense that it does store redundant data — parity
data — on one of the disks. The redundant data is used to calculate
the missing data when a disk goes missing, ensuring that users can still
retrieve the data without noticing a problem.
Be comfortable with the RAID levels when preparing for the exam. Check
out Book II, Chapter 5, to see how to create volumes in Windows.
Data encryption
Encrypting data converts information to an unreadable format so that if
folks gain access to the data, they cannot understand it. In the cryptography
world, encryption is described as changing plain text to cipher text. As you
can likely intuit, decryption converts cipher text to plain text.
There are a number of ways to encrypt data on the hard drive:
✦ EFS: The Encrypting File System (EFS) is a feature of NTFS and can be
enabled through the file properties. After the file is encrypted, it can be
read only by authorized persons. To read more about EFS, check out
Book V, Chapter 4.
✦ Bit Locker: Instead of encrypting data at the file level with EFS, you can
have Windows encrypt the entire partition or volume, which protects
all data on the partition, including the Windows OS, the Registry, and
the data. With Bit Locker, data is encrypted by using keys stored in
a TPM chip or a USB drive, depending upon how Bit Locker has been
configured.
✦ Third-party software: You can also use third-party software to encrypt
data. For example, you can use the free program TrueCrypt (www.true
crypt.org) to encrypt all your data into a TrueCrypt file and then
copy the file to a USB flash drive.
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