These days business owners and managers are quite familiar with “the cloud.” But many don't realize that the cloud actually comes in two distinct flavors.
What most people have in mind when they speak of the cloud is offerings like Amazon Web Services (AWS) or Microsoft Azure, which are set up to host the data and applications of any customer who desires to use that platform. Because they are available to be shared among all comers, and are accessible through the public internet, such services are called the “public cloud.”
A distinguishing feature of the public cloud is that the data of companies that use it is no longer physically under their control – it's housed in the facilities of the cloud vendor. With large public cloud providers like AWS and Azure, the location where a customer’s data is actually stored may not be even be in their own country, but could be halfway around the world.
The fact that public cloud facilities can be accessed by multiple users over the internet is what permits the reduced costs and increased convenience that makes these services attractive to multitudes of users. On the other hand, it's those very features that cause many companies to choose to deploy their own in-house private cloud instead.
For some, it's important to keep their most sensitive data under their own direct control on their own premises. Often they are concerned about security, fearing that data stored in the public cloud and accessible through the internet is more vulnerable to being stolen or corrupted.
Companies in regulated industries often face legal requirements that cause them to insist on keeping their data at home. For example, businesses that deal with medical records have a regulatory duty under HIPAA "to ensure the confidentiality, integrity, and security of electronic protected health information."
Sometimes companies simply need for their data to be close at hand because they are running high performance workloads that require faster response times than the public cloud can provide.
If for any reason your business has concerns about committing sensitive data to the public cloud, you can still gain many of the advantages of the cloud computing model by deploying your own private cloud.