Fast Hybrid Approach For The Exact String Matching Problem Via Raita And Berry Ravindran Computer Science Essay

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In this era of rapid technological advances, the biggest problem with computers is how to keep data safe and backed up from loss and destruction. A backup strategy may be defined as copying a person's files and/or folders from one computer in a location to another computer in a different location. The outcome would be positive if the user would need to get any of their information back if there would be a loss on their main machine. In the computer world, losing data can be very hard to come by. Even though it is possible for a person to be able to regain their data after an incident, it is always easier for them to get their files from a backup source than from a failed hard drive disk (Stevens). Usually, the hard disk is the first piece of a personal computer to fail. If it is unsuccessful, a consumer or an entire company cannot function until that drive has been repaired or replaced and data is restored if backups were done ("Remote Desktop Services"). If data was not backed up, their information could be lost forever and they would have to start from scratch. Nobody likes to back up their files or folders. One major excuse articulated is that it consumes too much time to accomplish. However, one day it might save someone or a business from a total meltdown.

Contributor David Cartwright points out that "backups are probably the most essential component of any corporate network, but are also one of those things that are done wrong with dreadful regularity." In addition, backing up an entire system might be faster and easier than ever before with new technology emerging every day, ensuring security for that person's information in any situation. No matter the scenario, backups are essential if the person's hard drive crashes, a thief steals his/her notebook, or he/she realizes that they need the previous revision of a significant spreadsheet that they changed sometime earlier (Spector). With data recovery, it is not assured that a person will be able to get all their information back from a mechanical failure. Data recovery is an extremely complicated and tedious task that a trained professional may experience as the process of recovering data progresses. Many different choices for data backup are available that do not take much time. Some examples include external hard drives, USB drives, CDs, DVDs, and online storage websites. All these choices make it easy to put files into them. Additionally, they are affordable depending upon the user's requirements (Stevens). Recent operating system built-in tools are making backups easier than previous operating systems. The objective of this research paper will focus on backing up files, folders, and system resources within an operating system and how to fix the operating system and its files. No longer does it take a lengthy amount of time and a lot of floppy disks to backup data. With new technology comes new directions, new tools, and new solutions.

Microsoft Windows XP does not truly have a boot disk like older operating systems have, but a disk can be formatted with Windows XP and the Windows XP boot files can be copied over to the disk. This disk can then take the place of a corrupted boot sector on a Windows XP system. In Windows 2000 or XP, a message appears "at the bottom of the splash screen at the start of the boot process, telling you to press the F8 key to see the advanced boot options" (Miastkowski). After opening the boot menu, choose Safe Mode. "Windows 2000/XP has a Safe Mode with a Command Prompt option that loads cmd.exe as your shell application" (Microsoft Corporation). If the system still does not boot, Windows 2000 allows users to create an Emergency Repair Disk (ERD) which contains a small replacement version of the system account database and a major portion of the system registry. The ERD is not required when performing an Emergency Repair with Windows XP because it can not fit the required files onto a disk. The Windows 2000 and Windows XP backup software is greatly improved over Windows NT 4.0 software. Windows 2000 and Windows XP backup software picks up where its predecessor left off, allowing users to schedule regular automatic backups and to back up to nearly any medium they like. Even though the tool is new, Microsoft has kept the name of ntbackup.exe, and supports all the old command line switches for backward compatibility. The backup utility allows them to create a backup of all local files on their disk drives, as well as the system state.


Windows XP Backup or Restore Wizard. Personal photograph by Jennifer Barbera. 18 February 2010.Consumers start a typical backup by launching the Backup utility, which can be done in one of two ways: Run ntbackup.exe, or Choose "Start- All Programs- Accessories-System Tools- Backup" (Miastkowski). The first time they launch it, it launches in wizard mode, which can be used for backup and will allow them to backup files using simplified or default settings. If they don't want to launch it in wizard mode, clear the Always Start in Wizard Mode check box in the Backup or Restore Wizard (see fig. 1) dialog box and the click the Cancel button or the Advanced Mode hyperlink. To schedule a basic backup of a system without using the wizard mode, there are many steps that need to be followed and they can be found on the Microsoft Website. After scheduling and running a backup, users can log onto the computer by logging on as the backup user account that was specified when scheduling the job. With Windows XP, Microsoft introduced a new system for backing out of driver changes known as System Restore. This restore point can be used to restore the system to a previous state in the event of an immediate failure. It's like having an undo button for the OS. Restore points are a replacement for the F8 boot option of Last Known Good Configuration although Microsoft Still supports the older and widely known Restore feature. Manually "creating a restore point or restoring your computer to a previous restore point is done through the System Restore Wizard" (Harder). The steps for that option are also available on the Microsoft Website. Another recovery method is to use a rescue CD. One that is very popular with Windows XP is BartPE. PE stands for Preinstalled Environment, which is a minimally installed copy of Windows XP that runs off a bootable CD.C:\Users\Jonathan Chirino\AppData\Local\Temp\\XP\1.gif

Microsoft Window Vista, released to the general public in 2007, is the Operating System designed to replace Windows XP. Vista was released in five different versions: Vista Starter, Home Basic, Home Premium, Business, and Ultimate editions (Andrews 41). For this part of the research paper, the casual home user, running Home Premium or Basic, is considered the client who needs to backup and plan for a possible operating system or hard drive malfunction. Windows Vista has a backup utility that is officially called the 'backup and restore center'. This 'restore center' gives the user the option of backing up specific types of media and choosing the place where the backup media is saved. The restore center also lets users schedule backups automatically on a specified time schedule. Once the backup is made, the user can choose another complete backup or to have to restore center simply add changes in the backed up media to the backup file. Windows Vista limits the type of files they can back up to eight different categories: Pictures, Music, Videos, E-mail, Documents, TV shows, compressed files, and Additional files. To setup and start the backup utility, follow the steps listed below:

1. Click on the Start button and choose the Control Panel.

2. Choose the 'System and Maintenance' icon and open the 'Backup and Restore Center'.

3. Choose between backing-up files that can be selected and backing up the entire PC as an image that can be used to recover from a hardware failure. The option to back up the entire PC is not available in the Starter or Home Editions.

4. Choose the location of where the backup file will be copied to.

5. Next, check the type of file or files to backup.

6. Lastly, Vista has a drop down menu where a user can schedule automatic backups.

Restoring a file or folder that was backed up is done in the 'backup and restore center' (see fig. 2). Vista gives the user a choice between restoring files from a backup done on that particular computer or from a different computer. The user is prompted to select which files/folders are to be restored and if they are to be restored to their original location. Once successfully restored, the user is notified of the successful restoration. The steps to restore are listed underneath:

1. Click on the start button and choose the control panel.

2. Choose the 'system and maintenance' icon and open the 'backup and restore center'.

3. Choose 'restore files'.

4. Choose between backing up using the newest backup file or an older one.

5. Select specific files or folders or do a search of the backup file wanted to be restored.

6. Click 'next' and choose the location.

7. Click 'begin restore'.

Figure 2

Windows Vista Backup and Restore Wizard. Personal photograph by Timothy Albers. 19 February 2010. Microsoft Windows Vista was used to replace the old Window's NT Backup wizard as the new backup operation, but the backup and restore center did not have some very important functionalities. Vista's new backup system was unable to make a recovery disc that could be used to boot one's system. Home Premium users' efforts to backup images were met with frustration, realizing that they had to buy third party software, because folder backup and system image were done with other programs (Soper). Microsoft Windows 7 continues to build on the innovative features of Vista and alleviates the Home Premium users' frustration by adding the functionalities it lacked. For example, to begin the Backup or Restore process in Windows 7, "open control panel and select Backup (see fig. 3) from the System and Security category" ("Windows 7 Help & How-to").C:\Users\Jonathan Chirino\AppData\Local\Microsoft\Windows\Temporary Internet Files\Low\Content.IE5\1DSW94Z3\Vista_backup_albers[1].jpg

Figure 3

Windows 7 Backup and Restore Wizard. Personal photograph by Jonathan Chirino. 21 February 2010.To set up the Windows' Backup simply pick the Set up Backup option. After clicking on the Set up Backup option, one should see the locations for storing the backed up data, and all the "internal, external hard disks, and DVD drives are listed" (Soper). Home Premium users do not have a network option, but others can save the backup on a Network in Business and Ultimate by simply clicking Save to Network; by choosing the default setting of "Let Windows Choose", the machine will create two backups. The two backups created by Windows are a system image used for disaster recovery; one backup of the data files in the libraries, desktop and Windows folders. Windows Backup "default" setting will always choose the data files for the current user and for any new ones too, but if one wanted to pick what to backup specifically then simply click the "Let Me Choose" and enter: 'Next'. Select the Save Settings key after evaluating the chosen settings, and wait for the completion dialogue to appear once the progress screen that displays the backup status disappears ("Windows 7 Help & How-to").

Another functionality that was proposed by Windows Vista but never realized was the system's ability to create a "System Repair" disc. Windows 7 has finally made this ability a reality by using the System Repair disc to engage a system of recovery features, which include the restoration of the system image itself. In order to create a System Repair disc one must first know if one uses a combination of 32 bit or 64 bit system to start a 32 or 64 bit system with the appropriate recovery disc. Simply insert a blank CD or DVD into the disc drive and click "Create Disc" to create a System Repair disc. It is also possible to restore a system image after creating a backup by clicking "Restore My Files" from Backup and Restore, and then use "Search" to browse for files or folders. Windows Backup will restore backed up selections to their original positions unless one wants a different location, in which case simply choose the "in the following location" option. The actual process of restoring a backed up image is similar in Windows 7 as in Vista (Soper).

To start a restoration of a backed up image: first be certain that the drive with the image is connected to the system and then restart the system. If one is using a repair disc then just select the Windows setup from the boot menu. Click "Next" on the opening screen if using the Windows 7 DVD, then click "Repair your Computer"; select next to open the System Recovery Option, and then select the installation to repair. The system will automatically scan the drives housing other system images to show those that are the most recent. To replace a failed hard disk, format the drive by matching the layout of the drives on the system image by selecting the "Format and Repartition" disk option, and watch the system reboot ("Windows 7 Help & How-to").

Windows 7 is reminiscent of Vista only. It offers the Home Premium users more functionalities and much better management by allowing users to copy data files, create system images that include the system's settings, programs and files. The new Windows 7 backup system gives the user the ability to choose a custom location for the data backup and the opportunity to decide whether it should include the system image during backup. The functions that were added to Windows 7 makes the new backup system more user friendly by making restorations easy of both data files and system images.

Figure 4

Apple's Time Machine. "Time Capsule." Apple Time Capsule. Apple Inc. n.d. Web. 22 Feb. 2010. <>. The standard for backing up materials across all operating systems is once a month. Some users do it more or less depending on the importance of their data. Apple computers are also subjected to this rule, yet offer an easy and maintenance free solution for their Mac's running Operating System Leopard (version 10.5) or higher. Two unique features that make the backup process for a Mac simple are Time Machine and Time Capsule (see fig. 4). Time Machine offers the ability of Apple computers that are connected to an external hard drive to backup all user files: movies, photos, music, user preferences, etc. After the initial backup of the system is complete, Time Machine will then update the backup system hourly. However, unlike other backup software, Time Machine will make incremental backups of the system, meaning it will only update the file that was modified or program that was added. If a file was mistakenly deleted or a program becomes unstable, a user can then refer to all of the backups Time Machine has made. Then using features such as "Cover Flow" or "Spotlight" search, it would then be possible to search for the missing file, or restore it to an earlier period ("Mac 101: Time Machine").

Another alternative to backup an Apple computer would be to purchase Time Capsule. Time Capsule is a unique backup and recovery solution because it does not have to be directly connected to a system. Instead, it can be used through a network to make incremental backups of one Macintosh or several. Because the initial backup is the largest and most time consuming, it is recommended to make the initial backup while Time Capsule is directly connected to the computer. After it is configured, it could then be directly connected to the router so that it can be accessible through a network. Time Capsule is designed to work with Time Machine to manage the computers backup and restoration files. This solution will work best at home or in a small office where multiple computers can access it, or need to be restored. These two unique technologies for Apple computers make backups and restorations relatively easy in case critical information was lost (McNulty).

The first step is to back up. The next stage is to protect the files and/or folders. To help protect important data, some ideas that users should follow after they backup their information are described below:

Keep the records away from the house and/or office and store it at another location. A user should keep the data stored at another location other than the location where the main computer is located. That data should be kept in a secret, well maintained location, like a box that is fireproofed or a safety deposit box.

A backup copy should be duplicated and kept in two detached locations. In a catastrophe, if one location gets destroyed where all information is lost, the additional copy stored at the other location can be used.

Keep files orderly and well documented. About every six months, clean up and delete any old files that are not used and compress the medium so that less space is used.

Use a password for the medium. If backing up personal or perceptive data, having it password protected is not a bad idea. However, make sure that the password is written down and left in a secure location so that a family member can access it if impairment arises. ("Backing up: What, how, where")

Much of the population ignores or overlooks their home or office personal computer backup needs. According to a survey conducted by Kabooza, about 82% of those who responded (which were about 4,257 people) do not perform regular backups, many of which have had severe critical loss of information. With generations coming and growing, involving computers into their normal everyday skills and lives and with new technology making it easier than ever before to backup any information, hopefully the required actions are learned and taken to prevent any loss of information and keep data secured. With critical time's currently taking place, having an up-to-date backup that is protected can have an extraordinary turnout in case of a tragedy.