“INTRODUCTION”

Data backup is said to be the best prevention for data loss. Now the question arise what exactly Backup is? It is a process of having duplicate copy of the original one. It is an activity of copying files or databases so that the data will be preserved in case of any accidentally or intentionally deletion of the data. It involves the saving of your data in two or more locations, so that if something happens to your computer, you still have your data reserved in backup. This allows you to keep your data even if you lose your computer. While you might think that the chances of having a major loss of data on your computer or even having your entire computer crash are very small, disasters happen and it is always best to prepare for the worst, especially when it comes to something as irreplaceable as your files.

In information technology, a backup or the process of backing up refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called “backups.”Since data is very important for higher efficiency, backup is one of the most powerful ways to protect against data loss.

Backups are useful primarily for two purposes. The first is to restore a state following a disaster (called disaster recovery). The second is to restore small numbers of files after they have been accidentally deleted or corrupted. Data loss is also very common. 66% of internet users have suffered from serious data loss.

Backup Objectives-

There are various reasons for data loss like viruses, application problems, human errors, operating system failure, and many more. Backup plays a vital role for the businesses or the organizations, which spends lot of time on the computer for their personal or business dealings.

No matter what happens to your computer, you should backup because some data can be replaced but the most important files which cannot be retrieved may cause you a severe problem, as a result backing up the files, documents etc is very necessary.

DATA BACKUP STRATEGIES-

When you start thinking of backing up the data, first thing comes to your mind what data to backup. Well it depends on how frequent you use your computer, how much your data is important. So before Backing up your data, the capacity of your data place an important role, identifying the capacity of the backup medium to the quantity of data you propose to backup is very important. It’s a good idea to have something big enough to put a single copy of all your information on one physical thing.

Figure:Data backup strategies

Data backup can take many forms. After all, any medium on which you save your files apart from your primary computer is considered backup. You might even want to backup your data in more than one location, just in case. If you depend highly upon your computer and upon the files contained therein, you can never be too careful when it comes to protecting your files from disaster.

OFFLINE DATA BACKUP-

The offline data backup method may be the better option for you if you’re concerned about transmitting sensitive data (encrypted data) over public internet pathways. There are a number of different backup media types to choose from. The most popular type of offline backup system is probably a specialized backup server. Other popular types of backup systems incorporate burnable CD/DVD drives or digital tape drives.

In the earlier days, if a person holds the huge data it would be difficult for him to back up the whole data, as the only media available was the floppy disks which consisted just over a megabyte of data. But now the technology has fully changed, a person can save his data according to the capacity of his data, he can choose the appropriate Medias like:

• Tape
• Hard disk
• Optical Disk like CD, DVD etc.
• Floppy Disk
• External Hard Drive
• Remote backup service etc.

The most basic method of backing up your data is on a simple floppy disk. However, this method is essentially obsolete, as it is difficult to even buy a computer which includes a floppy disk drive these days. With CD-Rs and now DVD-Rs being cheaper than ever, it is possible to store far more data on a single disk than was ever possible with a floppy disk.

ONLINE DATA BACKUP-

You can also backup your files online. Data is backed up over a networked connection (most likely using the TCP/IP standard protocol of the internet) to a remote location (ideally). An offline data backup most often refers to data that is backed up on-site, rather than to a remote location. The offline method will require some type of on-site hardware and media such as digital tape drives or CD/DVD burners.

When considering an online backup method, there are a couple of ways to approach the process. You could set up your own off-site (remote) backup location using a secondary office. This would require networked PCs or a server(s) to be installed and configured at the backup site along with appropriate data encryption software that would be used to secure data before transmission to the backup site. There are many third-party applications available that can do this. Another popular option would be to use an online data backup service. This is a great low-maintenance approach because the service does most of the work for you.

There are many companies that provide online storage drives which will allow you to store your data without the need for disks or drives or anything of the sort. This can be very beneficial as you know that you will always be able to obtain your data, without having to worry about having the proper CD-ROM or DVD-ROM drive, or anything of this sort. If you do not have any such storage devices on your computer, you might want to consider online backup. All you need is an internet connection and you can begin saving all the files you want online. However, if you are working with a dial-up connection, this can be a slow process if you are saving large files, more than simple documents and the like.Backing up is an important task for any individual or organization, however as data becomes increasing important in business, the loss of data is often sharply felt in terms of cost and effort. Whatever method we choose, but backing up your files are very important because it is the one of the safest method to protect against the worst.

Figure: Online data backup

Now the big question arises. Which backup system is best? Online or offline?

The answer really depends on what type of data you’re backing up, how much data you’re backing up, and your support model. Small businesses don’t always have dedicated I.T. support and this responsibility may need to be shared.

So who knows your data the best? This is the individual that you should seek guidance from when determining what needs to be backed up. Is it a small amount of super sensitive, confidential data? If that’s the case, you may feel more comfortable using the offline backup method. Is it a huge amount of non-sensitive, publicly distributed material? If that’s the case, why not go with an online backup service and save yourself the hassle of maintaining backups at your local site. As you can see, the answer is very subjective. You know your data best so you’ll know the right backup method to choose. Common sense should rule this decision.

However, what if your specific data set doesn’t fall nicely into one category? What if you have a mix of highly sensitive data and publicly distributed data as well as categories in between? So is it feasible to use both online and offline systems? Absolutely! Not only is it feasible but it gives you more flexibility (i.e. more options) and may be more cost effective than limiting yourself to one or the other. In most cases, an online backup service will charge you by the gigabyte for a set amount of storage. If you were to purchase the lowest amount of space that could store all of your publicly distributed data, you could setup a small digital tape drive system locally to handle all of your highly sensitive data.

Four Backup Approaches

There are four backup approaches that are commonly used on personal computers today. These are the following:

1. File Backup Approach: The File Backup Approach is the oldest and most common backup method used on personal computers. I would estimate that of the dozens of backup utilities available, 90% of them are file backup utilities. With this approach, you select which of the many files stored on your main hard drive to backup and the utility will copy each of these files individually to your backup device. It is possible to select all of the files on your main hard drive to backup, but this approach is not very good as we will see later.

2. Clone Backup Approach: This approach became popular a few years ago to let you adequately backup your entire hard drive. With the Clone (or Copy) Backup Approach, you make an exact copy of your main hard drive to another hard drive inside your computer. Then if anything happens to your main hard drive, you simply replace it with the cloned hard drive and you are up and running again. While this approach seems simple and straight forward, it is not a very efficient way to do backups today.

3. FullBackup Image Approach: The imaging approach copies the physical sectors of your main hard drive to the backup device instead of copying each file separately. So, the backups were much faster than individual file by file backups. Images could also be quickly restored to a new hard drive on your computer and let your computer be used again in a few minutes. The backup images could also be compressed to save room on your backup device. While much better than the first two backup approaches, this is not the most efficient way to store your backup images.

4. Full & Incremental Backup Image Approach: The next step in improving the backup technology came when a new product was introduced that could make not only full back up images of your main hard drive, but could also make incremental backup images of just the changes to your hard drive since the last backup was made. This permitted frequent backups to be taken for maximum protection, but still conserves your backup storage space. Combined with an external hard drive to save your backup images on, this was the basis of the Perfect Backup Approach and is the best way to do backups today.