Keep PC Safe

With the increasing reliance on computer based systems to manage all aspects of our lives,

more emphasis is being placed on the development of backup systems as a necessary tool to

promote rapid and reliable data recovery. All computers and systems have the possibility of

failure. Planning for that failure can reduce the impact it may have on your business operations.

Traditional backups have usually consisted of tape-based systems that backup data and

transactions on a daily basis. For applications that require a higher degree of security, like

credit card transactions or systems that process a large amount of data each hour, a daily back

up may not be sufficient protection in the case of disaster. Fortunately, continuous backup

solutions exist. Here data is automatically copied to a backup system every time a change is

made to that data. This is in essence how the Unix file system works by saving multiple

versions of the same document. Continuous backup allows the user or a system administrator

to restore the data to any point in time.

There are many technologies that are designed for continuous backup. There is considerable

effort being done right now to create some sets of standards for continuous backups. The key

to continuous backup is the ability to record all data changes as occur, and to time-stamp them.

This means that one can reset the file to any point in time, rejecting any changes made after

that. Windows XP implements a form of continuous backup with their system restore function.

However the idea of full continuous backup is a much more powerful concept.

It is important to differentiate between continuous backup and what is known as taking

snapshots. Unlike snapshots, continuous backup does not store complete images of the drive

taken at given intervals. It just records the changes made to files. Snapshots generally require

far more storage space than a continuous backup solution.

Continuous backups are quite a bit different from traditional backups. Traditional backups can

only restore data to the point at which the backup was taken. With continuous backups, there

are no schedules. When data is written to disk, it is also written to a second location. This

eliminates the need for nightly scheduled backups.

Near continues backup is a variation of continuous backup where the data is backed up on

regular, those discreet, intervals. A typical length of time for a near continuous backup interval

is a couple of minutes. This reduces the demand that a continuous backup system requires,

while still providing a high level of data protection against unforeseen occurrences.

It is important to note that some backup systems are called continuous even though they only

perform the backup every hour or so. In essence, they are actually a snapshot system, and do

not offer the full flexibility of a continuous backup system.