What is cloud storage? A comprehensive evaluation of data-as-a-service

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Cloud storage (opens in new tab) remains one of the more confusing tech terms around; nearly a quarter million queries on “what is cloud storage” were carried out globally over the past 12 months according to Google, a 21% rise over the same period the year before.

At its simplest, Cloud storage is disk space, usually in a data center, which you can access to save or retrieve files. That space is usually owned and operated by what is commonly called a hyperscaler (e.g. Google, Facebook, Apple, Microsoft, Amazon, Tencent or Alibaba). 

That is an important point: that space is owned by them, not you, you are only renting it (as you would do in a condominium or a flat); in other words, you are leasing a hard drive or SSD or tape (or a portion of it) in the cloud. For the purpose of this article, we will narrow our focus on user-friendly cloud storage where one can store digital data.

Data-as-a-service: A paradigm shift 

If you are of a certain age, you may remember buying audio CDs off the shelves of supermarkets; you would own the CD and you’d be able to do whatever you want with it. Then came Spotify and everything changed, including the fact that you’d be paying a monthly fee and essentially get access to the biggest music library that ever existed. No need to buy CDs or carry your collection around.

Cloud storage is essentially the same except that you usually pay based on usage (Backblaze being one notable exception). You can get as much data as you want, anytime and not have to worry about things that come with owning a storage device: theft, aftersales, power consumption, incidents/accidents and subsequent data recovery, being able to access data anywhere etc.

Cloud computing vs Cloud Storage, what’s the difference?

You can look at your own phone or computer as a comparison. At its simplest, a computer does three basic things to data: transmit it, store it or compute it; cloud storage is therefore a subset of cloud computing, only remotely. Cloud computing is used generically to describe any sort of on-demand computer-related service that can be done by a service provider, usually as a subscription. Check out our more comprehensive write up on Cloud Computing.

Amazon was the first one to launch cloud computing at scale with a cloud storage service, almost 17 years ago. S3 (Simple Storage Service) is an object-based storage service, which differs from a normal business or consumer cloud storage; it spawned a dozen or so other storage-based services on AWS. AWS (opens in new tab) has grown into a massive sprawling ecosystem with 25 categories as of October 2022 and more than 200 services.

Amazon’s definition of Cloud Storage talks to a business audience but applies to consumers as well. “It is a cloud computing model that stores data on the Internet through a cloud computing provider who manages and operates data storage as a service. It’s delivered on demand with just-in-time capacity and costs, and eliminates buying and managing your own data storage infrastructure. This gives you agility, global scale and durability, with “anytime, anywhere” data access.”

Where is cloud storage data located? 

As mentioned earlier your data is most likely to be located in a data center, either owned by a hyperscaler or by a data center operator. This is where data is stored in the cloud. A service provider like iDrive will rent space and amenities (lights, electricity, cooling) and deploy its own cloud storage services, in a way similar to dedicated server hosting, colocation providers or bare metal hosting.

The best cloud storage providers will save multiple copies of your data across multiple data centers to mitigate the risk of your data being lost should there be a catastrophic event (e.g. Tsunami, Typhoon, earthquake, war or even fires). That does happen even to the biggest players and could have a long lasting negative impact on businesses.

Others go even further by storing your data on thousands of devices, creating a large number of mirrors that make losing your entire data virtually impossible. Cubbit and Storj are two of the most well-known proponents of this radically different approach to decentralized cloud storage, one which embraces peer-to-peer technology, the same philosophy behind torrenting and bittorrent

How many cloud storage providers are there? 

Not only do hyperscalers have their own cloud storage services (Google Drive, Amazon Drive, Apple iCloud, OneDrive, Terabox), they also host over cloud storage services on behalf of other firms. For example, Dropbox is one of Amazon Web Services’s biggest customers. Setting up your own cloud storage provider is so easy we’ve got a tutorial for that.

As such, there are dozens of services that offer some form of cloud storage: you might see them described as online backup, cloud backup, online drives, file hosting and more, but essentially they’re still cloud storage with custom apps or web consoles to add some extra features. As of October 2022, we’ve reviewed around 50 of them which is probably a quarter of the total number of providers in the market.

You won’t have to look far to find your nearest cloud storage service, though, because there’s a very good chance you have access to one already. Facebook and Twitter provide free cloud storage when they allow users to store photos and videos on their servers, for instance, while even the most basic free Google account gets you 15GB of cloud storage space via the Google Drive app.

What are the benefits of cloud storage?

Saving your data to the cloud protects you from all kinds of data disasters. Whether it's a dead hard drive, a lost laptop or a ransomware attack, having your files out of harm's way means you'll avoid a whole lot of pain.

Sharing files via the cloud is safer and easier than many alternatives. Send something by email or copy it to a USB key, and your data doesn't have much protection beyond wishful thinking ('no-one else has access to that email account, right?') Cloud storage providers usually enable file encryption from the moment they leave your device, then give you a range of secure ways to share them with others.

Many services allow you to access files directly from your storage, without downloading them first. You might be able to stream a huge video from the cloud, for instance. You can often collaborate on files with others, perhaps with two people editing a document at the time.

Storing files in the cloud gives them real protection from damage, too. Accidentally deleted something? You'll usually find it in the Recycle Bin. Made a big mistake in the last few edits? You can often restore any previous version of the document from the last 30 days, and sometimes more - a real life-saver.

Can cloud storage providers be trusted?

It’s important to know a cloud storage service can be trusted with your files, so most providers go to a lot of trouble to make sure they’re safe. They’ll upload and download files via a secure encrypted connection, for instance. Maximum security data centers ensure no unauthorized person gets access to their servers, and even if someone did break in, leading-edge encryption (opens in new tab) prevents an attacker viewing your data.

While cost is an obvious factor to consider when choosing a cloud storage provider, it is secondary to trust. After all, what’s the point of saving a few dollars a month if you can’t be 100% sure that your data is safe, untampered and 100% private? The best secure cloud storage provider is likely to be one of the bigger players in the cloud storage market.

Want to know more about cloud storage?

Fran Villalba Segarra, CEO of cloud storage company Internxt, wrote extensively on how cloud storage works and on whether cloud storage is safe, secure and private and we found out that the term cloud storage actually dates back from 1896 and was used to describe just that; how to store clouds. Andrew Martin, UK MD for Egnyte, a business cloud storage provider, investigated the pros and cons of on-premise vs cloud storage setups. Oh and before we forget, make sure you check our comparison, Cloud storage vs Cloud backup vs Cloud sync, written by Jay El-Anis from UK cloud storage provider, Zoolz

Desire Athow
Managing Editor, TechRadar Pro

Désiré has been musing and writing about technology during a career spanning four decades. He dabbled in website builders and web hosting when DHTML and frames were in vogue and started narrating about the impact of technology on society just before the start of the Y2K hysteria at the turn of the last millennium.