Backup is one of the oldest needs in computing. Whether it's hard disk failure, computer theft, or just a wandering three year-old with a fruit juice carton, it's very easy to lose data on a computer.
There's a debate about the best kind of backup, but storing your data offsite and online is a good option.
Although at one time offsite backup was niche and often expensive, the cloud has brought about a revolution in inexpensive storage, making backing up online inexpensive and fuss-free.
But with so many choices out there, how can we narrow it down? Rather than directly recommending services, here are requirements to consider.
Firstly, however, a word about the types of cloud storage available for workstations. Essentially, there are two: dedicated backup services and cloud sync services.
The former usually comes with a client that's able to watch files or folders (including types of files) and back them up when they change. A popular example of this is Mozy. The downside is that restoring files is more involved; it isn't expected users will restore unless they have to.
Cloud sync services take a different approach, adding a magic folder or drive to your computer, the contents of which are automatically and invisibly synced online. A popular example of this is Dropbox. Some services offer client software that can also watch files and folders anywhere on your hard disk and back them up too, such as that offered by SugarSync.
Cloud sync is a more immediate form of backup, and if you create and edit files within the magic folder everything will be backed-up automatically.
When it comes to choosing any kind of service, the first question to ask is what computing platforms are supported. If you're backing up a Mac, for example, then being able to access the data from a PC client is vital should the Mac die; PCs are commonplace, but Macs are rarer. Some cloud storage services offer clients not only for Mac and PC but for mobile devices like iPhones and Android phones, too.
Consider security. Your data will be undoubtedly be stored encrypted but that doesn't amount to a hill of beans if the sign-on system is weak. Some cloud storage providers require you to use your email address as a login name, for example, meaning that anybody who wants to access your data surreptitiously only has to guess your password. If you choose a strong and unique password then this shoudn't be an issue, of course.
As for the actual file uploads, there are essentially two approaches. The first is to back up entire files each and every time. If the file is modified, then the whole thing is backed-up afresh--annoying if you've done little more than tweak a 10GB movie, for example.
The second method is to work out the difference between the old and new files, and only back up the new data--a process known as diffing. This saves bandwidth, and also stops your Internet connection from getting choked with constant backup data.
Bear in mind the load the backup software places on your system. Some services boast of clients that have minimal impact. Some can seriously slow down your computer while they're aggregating files and putting them online. The only way to find out for sure is to use the free trial periods offered by various services.
A major concern is whether the company will stay in business. Startups sometimes offer amazing prices for cloud storage but require a leap of faith on behalf of users that they'll still be around next year. It's possible that even established services could disappear overnight, but more likely the owners will tell you if the service is to terminate, and give you a chance to make other arrangements or retrieve data. Companies like Mozy make a point of explaining how they're backed by a large corporation, making failure arguably less likely.
For those on a budget, it's worth considering a DIY approach using Amazon's Simple Storage Service (S3). Although designed for sophisticated users, S3 is available to anybody who wants it, and at its most basic is surprisingly simple to use. All you need to do is sign up and then create a "bucket," which is S3 terminology for a storage folder. Then you'll have to find some backup software that's able to connect to S3, and provide it with your public and private keys in order to log on.
Choosing an S3 backup client is just like choosing any other backup program. You should make sure you get a cross-platform client, for example, so you can restore files anywhere and at any time. Although there's strictly no need to encrypt data stored in S3 (data in a bucket is private unless you deliberately make it public), most clients will also encrypt it. That can create problems. Although clients normally use standard forms of encryption, such as AES, the specific method of encryption will probably tie you into using that particular client when it comes to restoring files. Don't assume you can simply dip into your bucket manually to grab files.
How cheap is S3? With S3 you pay for transfer in and out, as well as the storage space your files take up, although the individual fees are very small.
The initial transfer of around 50GB of files will cost about $5, for example, at 10 cents transfer fee for each gigabyte uploaded. Every month the charges will be 9.3 cents of "rent" per gigabyte, making $4.65 in total, although if you upload a further gigabyte or two each month you'll be looking more at a total of around $5 per month. Assuming a growth of 2GB per month in terms of new files you decide to backup, a year later you'll be paying around $8 per month for 74GB of storage--still pretty good value.
If using an S3 backup client sounds like too much hassle, you could use one of the many FTP clients that support S3, and manually copy files to your S3 space when required. Again, you'll need to use your public and private key as your username and password, but aside from this there's no difference between using S3 and an FTP site. Files won't be encrypted but, as mentioned, S3 is technically secure (although hackers gaining access in some as-yet unknown way will always be an issue). You could also use something like TrueCrypt, a cross-platform and open encryption package, to encrypt any particularly sensitive data before uploading it.