Solar power generation around the clock

(PhysOrg.com) -- A Californian company, SolarReserve, is developing a solar power system that can store seven hours' worth of solar energy by focusing mirrors onto millions of gallons of molten salt, allowing the plant to ...

Mars Orbiter's Computer Reboots Successfully

(PhysOrg.com) -- NASA's Mars Odyssey orbiter properly followed commands today to shut down and restart, a strategy by its engineers to clear any memory flaws accumulated in more than five years since Odyssey's last reboot. ...

Generators that relieve power grid worsen ozone pollution

Cornell engineers have found that firing up diesel backup generators in non-emergency situations triggers rising atmospheric ozone concentrations due to additional nitrogen oxide emissions. They reported their findings Jan ...

Space station computer outage may force spacewalk

A computer outage at the International Space Station may require a spacewalk by astronauts and threatens to delay next week's launch of a commercial supply ship for NASA.

Security flaws could taint 2012 US election: report

Security flaws in voting technology in a number of US states could taint the outcome of the 2012 election, a study concluded Wednesday, saying it was "highly likely" some systems will fail.

Cloud computing's ubiquity brings down prices

If you've ever had your laptop stolen, watched your toddler baptize your PC with Pepsi, or had your MacBook come to a cold, dead stop, you know that the digital memories we store on our home computers are anything but indelible.

Oldest US nuclear reactor: a 'disaster' in waiting?

A sleepy New Jersey town has popped onto people's radar screens because it has the oldest running nuclear power plant in the United States -- and, some say, the most dangerous.

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Backup

In information technology, a backup or the process of backing up is making copies of data which may be used to restore the original after a data loss event. The verb form is back up in two words, whereas the noun is backup.

Backups have two distinct purposes. The primary purpose is to recover data after its loss, be it by data deletion or corruption. Data loss is a very common experience of computer users. 67% of Internet users have suffered serious data loss. The secondary purpose of backups is to recover data from an earlier time, according to a user-defined data retention policy, typically configured within a backup application for how long copies of data are required.

Though backups popularly represent a simple form of disaster recovery, and should be part of a disaster recovery plan, by themselves, backups should not alone be considered disaster recovery. Not all backup systems or backup applications are able to reconstitute a computer system, or in turn other complex configurations such as a computer cluster, active directory servers, or a database server, by restoring only data from a backup.

Since a backup system contains at least one copy of all data worth saving, the data storage requirements are considerable. Organizing this storage space and managing the backup process is a complicated undertaking. A data repository model can be used to provide structure to the storage. In the modern era of computing there are many different types of data storage devices that are useful for making backups. There are also many different ways in which these devices can be arranged to provide geographic redundancy, data security, and portability.

Before data is sent to its storage location, it is selected, extracted, and manipulated. Many different techniques have been developed to optimize the backup procedure. These include optimizations for dealing with open files and live data sources as well as compression, encryption, and de-duplication, among others. Many organizations and individuals try to have confidence that the process is working as expected and work to define measurements and validation techniques. It is also important to recognize the limitations and human factors involved in any backup scheme.

This text uses material from Wikipedia, licensed under CC BY-SA