Cloud or On-Premises?

blog-Cloud storage or On-Premises

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When you are planning to put more storage space in your data center, there are many aspects you have to consider before you made a choice.  In recent years, more and more people take cloud storage as an option, while others still pick traditional on-premises storage devices as their first option. Which one fits you the best?

Cloud storage is built to let you start using it on the very first day you apply for it. You will save plenty of time building storage architecture. Using cloud storage, you can access the same files across different devices. Hardware maintenance is no longer a problem, make sure you have internet access, and there will be nearly no downtime.

However, because the cloud storage is built at the data center that miles away from your device, you will need to take a longer time to access your data, which is a critical factor for some mission-critical applications. And you must regularly pay to keep your data in the cloud.

Some of the issues mentioned above can be solved by adopting On-premises storage. In an on-premise environment, data packages usually move within LAN, you will get much better response time for your application. And as the drive is cheaper now, you can get much more storage space at the same price.

Be aware that you will need deeper technical knowledge to manage these devices, and it takes days or weeks to set up the storage before you start using it.

Let’s look at some important aspects you need to consider before you decide where to put your data:

Use it for Backup and Sync

What is the main purpose of the storage you are going to have?

Let’s say that you will use it as a backup for your main storage, will you need just one copy of it, or need to keep more than one copy? Different backup strategy consumes different among of space. If you frequently need more space, and you decide to go with the cloud; you need to select the right cloud service carefully; otherwise, you will find out that the cloud service costs you much more that you expected. Backup speed is another shortage for cloud storage, you won’t want to see that the nightly backup is still on-going when you go to the office in the morning.

Consider on-premise storage If you think you will have these problems. In an on-promise environment, data packages usually move within LAN. The backup time will be fast, and for most storage providers, it is easy to expand the storage space if you are running out of storage space. Check out how QSAN protects your data with different backup solutions.

If you need to sync your files so you or other people can access the same file using different devices. Cloud service provides what you are looking for. No matter you are working within the same building or in another country, you have no problem access your data using cloud service.

Using the public cloud, all information is kept in the cloud, and as you create it in the office, you can still access it in other places, like a meeting room at your client’s office, in the airport – as long as you can get online. You can even share information with others using the share function, which should be available from every public cloud provider. These days, most storage providers provide the same user experience as a cloud service, you can build on-premise storage, and make it accessible to the outside world. 

QSAN XCubeNAS let you configure it as a public cloud easily and continuously provide the rich function to let you share files, backup, and mirror between different storage devices. You will have much more than what you can do with cloud service.

Response Time

The cloud today is mainly relegated to archival data, backup, disaster recovery (DR) and other workloads that do not have strict performance requirements. However, if the program response time significant for your application, you need to think twice when looking for cloud solution.

Generally, latency significantly affects how usable and enjoyable devices and communications are. Those problems can be significant for cloud service communications, which can be especially prone to latency for several reasons.

There are lots of possibilities that would result in latency, e.g. the standard number of router hops or ground-to-satellite communication hops on the way to the target server.  The data center of a cloud provider can’t be everywhere and close to every end-user, so the big distances created to result in unavoidable latency.

The latency of a cloud service might range from several tens to hundreds of millisecond, by contrast, on-premise storage usually provides satisfied latency for applications. For example, QSAN XCubeFAS provides 1,200K IOPS under 1 millisecond, which meets the performance requirement for the heavy business load.

If your storage is built for these types of business, always consider on-premise storage as your first choice. You will not want your customer to stop business because they cannot tolerate the slow response time of your site!

*For your reference, many cloud providers like AWS and Azure provide a tool to let you check the latency from your place to the cloud data center.


Budget control is one primary consideration. Carefully estimate the storage growth rates and calculate how much storage space you need for the next year. The chart below shows the estimated cloud storage cost provided by each could be storage vendor (regardless of the access type, the number of users, and additional benefits).

Storage/PriceStorage/PriceDropbox Google oneOnedrive
6TB$99.99 /yr
*The price unit is USD and based on the pricing of each vendor provided by 14 June 2019. 

Different usages need different storage space, if your storage need grows every year, cloud storage service will charge you more and more each year, since you need to pay every byte you use every year.

If you build on-premise storage, the storage cost will be one time, and you don’t have to pay for what you’ve already built every year. Even public cloud provider, Dropbox began to move users  of its file-storage service away from AWS’s S3 storage service and onto its own custom-designed infrastructure and software, and the cost benefits were immediate.

Budget control is one advantage to adopt on-premise storage, but there are always spendings you need to take care of. Remember to consider other expenses like drive replacement fees, electricity fees, and IT maintenance fees. Make your calculation to see which cost you less.

Data Security

When you have your data in the cloud, you may want to know one thing: Is someone using your data secretly? Make sure to check the privacy statement of your cloud storage providers. In principle, each cloud storage vendor has its cloud privacy statement, carefully read the announcement, and make sure that it is acceptable.

For on-premise storage, you have full control of your data, and everything can be private, and the data is for your usage only. The Storage device should provide privacy control functions such as access control, log, and data encryption.

One technology QSAN provides to protect your data is WORM. WORM technology is designed to prevent intentional or accidental modification of data in a certain period. Files and folders under WORMs protection can only be read in a user-defined period. It is unable to modify any files or folders until the period has expired. WORM will protect your confidential data from unauthorized modification and threat, ensuring the correctness and integrity of your data.

If you are in an environment, such as a bank, military, that requires high-level security control, you should consider storage vendor that supports SED (Self-Encrypting Drive). SED has built-in an encryption controller and an encryption key on the disk drive itself. It can secure current data by auto-locking if a drive is misplaced or stolen from a system. Every QSAN storage product supports SED. You can read more about QSAN SED here.

Hybrid-cloud: Between Cloud Storage and On-premises Storage

One good strategy is to take advantage of both Cloud service and on-premise storage.

You can use cloud storage for an application that requires lower security and can share information in real-time, and use on-premise storage for your business-critical operation and application that need to handle sensitive data.

You should deploy a backup architecture to back up your cloud storage to on-premise storage, and vice versa.

If your on-premise storage device provides bridge functions to the cloud, you will save an enormous amount of time on the transfer process. The image that If there is no direct bridge between your NAS device and Cloud, you will need to use another computer to drag data from NAS and drop it to your cloud drive, and every data package must be transferred via your computer, and you will spend great among of time moving data at this route.

XCubeNAS provides functions to let you directly talk to cloud providers like Alibaba, Amazon, Dropbox, Google Drive, and Onedrive. With a few clicks, you can build hybrid-cloud storage and efficiently move your data between public cloud and on-premise storage. QSAN will be more than happy to share the deployment strategy, please contact us for more information.


The above suggestions are several things you will need to consider before you spend on any storage solution.

There is no one-fit-for-all storage solution, and you need to understand the type of data that will be saved first and decide what kind of storage solution is the best fit.

Cloud storage provides a quick solution to let you get more storage space without worrying about storage hardware. On-premise storage, on the other hand, provides much better response time and gives you full control of the room (and your budget).

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