RAID stands

RAID stands for Redundant Array of Independent Disks refers to a technology in computer data storage used to implement fault tolerance features on computer storage media (primarily hard disks) by using redundancy (buildup) of data, either by using software , as well as a separate unit of hardware RAID. The word "RAID" also has some acronym for Redundant Array of Inexpensive Disks, Redundant Array of Independent Drives, and Redundant Array of Inexpensive Drives. These technologies share or replicate data into a separate hard disk. RAID is designed to improve the reliability of data and / or improve the performance of I / O from the hard disk.

Since first introduced, the RAID is divided into several schemes, called the "RAID Level". Initially, there were five RAID levels that was first drafted, but over time, the levels have evolved, namely by combining several different levels and also implement some level of proprietary which is not a standard RAID.

RAID combines multiple physical hard disks into a logical unit of storage, using software or special hardware. Hardware solutions are generally designed to support the use of multiple hard disks simultaneously, and the operating system does not need to know how to work these RAID schemes. Meanwhile, software solutions are generally implemented within the operating system level, and of course make some hard drives into a logical entity that is used for storage.

Raid Levels

1.RAID O.
Meaning: The whole hard drive that is owned will serve as data storage. in other words we save the data into the disk will be in stripping the whole hard disk is a member of the RAID 0.
Example: 4 berkapasistas SCSI Hard Drive 72GB per disk configured with RAID 0, the total hard drive that can be used as data storage is the total (4 x 72 GB)
Pros: With RAID 0, capacity of hard disk for data storage is owned by the total of the entire hard drive you have, without any reduction
Disadvantages: If one drive fails in RAID 0, then the data will be lost without replacement.

2.RAID 1
Meaning: Hard drive in RAID 1 can be interpreted as mirroring, because half of the amount of hard drive is positioned as a RAID 1 is used as a mirror. In other words that only half of the overall hard drive capacity which can be used as data storage, half of them only serves as a mirror
Example: 4 SCSI hard drive capacity of 72GB configured with RAID 1, then only 2 hard drive (2 x 72 GB) which can be used as data storage, and 2 hard drive again (2 x 72GB) again used as a Mirror of the data.
Pros: If one hard drive that serves as a data storage fails / problem, then the mirror disk will automatically replace the hard drive fails its function until these are replaced by new ones, without any decrease in performance of the entire hard drive.
Disadvantages: Expensive RAID 1 can be said, because only half of the amount of hard drive that can be owned by data storage.

3.RAID 1 +0
Meaning: hard drives configured in RAID 1 +0 can be said in striping and on the mirror, in other words the data that we store in the hard disk will be stripping all the members of a RAID 1 +0 and also half of the existing hard drive will be on the mirror .
Example: 4 SCSI hard drive capacity of 72GB configured with RAID 1 +0 then the capacity can be used for data storage is 2 x 72 GB and the data stored will be stripping or distributed between two disk itself. berdungsi remaining 2 hard drive again as a mirror.
Pros: can be said to be similar to RAID 1 only read and write performance of hard drives increase compared to RAID 1
Disadvantages: EXPENSIVE as well as RAID 1

4.RAID 5
Meaning: In a RAID 5 hard drive there is a minimal restriction is used, ie 4 hard drives, why? because the existing distribution system is a RAID 5 and parity data.
Example: 4-capacity 72GB hard drive will be configured with RAID 5, then 3 x 72 GB will serve as data storage and 1 x 72 GB to parity.
Pros: If one of the hard disk fails, the function of the hard drive is still functioning.
Disadvantages: performance will decrease if the hard drive fails.

5.RAID 6
Meaning: In a RAID 6 also no restrictions on minimum level of 5 hard disk drive. 3 of them will be made in the data and 2 again as parity.
Example: 5-capacity 72GB hard drive will be configured as RAID 6, then 3 x 72 GB will serve as data storage and 2 x 72GB to parity.
Pros: in a RAID 6 maximum hard drive fails in the same time is 2 hard drive. so if two hard drives in RAID 6 fails, the function of the hard drive is still running.
Disadvantages: performance will decline if there is a hard drive fails.

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How Outlook helps to protect your computer from viruses
Posted on February 15, 2010 by Henry Dahlan
What is a virus?

Computer viruses attack the software of a computer, not the hardware. The basic definition of a virus is a program That copies Itself. Most common viruses are small programs That need to use a legitimate program or file in order to run. Most viruses today are written with malicious intent; as a result, They can cause damage to programs or data. Because the virus code must be run to have any effect, the computer files That Treats the data as pure, Such as. Txt files, are safe. For example, reading a plain-text e-mail message will not infect your computer with a virus.

In order to run, the virus code has to be written in an executable form, Such as an. Exe program file. HTML-format and RTF-formatted e-mail messages or Web Pages that contain Microsoft ActiveX ® controls or scripts, Such as Microsoft Visual Basic ® Scripting Edition (VBScript), Microsoft JScript ®, or other types of embedded program code, can harbor the virus That Pls run programs you open a message or view a Web page. Opening e-mail attachments can also infect your computer with viruses. Some malicious files can be constructed to take advantage of known vulnerabilities in the software in order to run destructive code. Microsoft Recommends That you protect your computer by applying all updates and patches for the software on your computer.