by FortressITX Dir. of Datacenter Operations, Salvatore Poliandro

What is the “Cloud”? What is “Cloud” computing? These are questions I get all the time. For the vast majority of people, the “Cloud” is a lofty term having to do something with computing or, let’s be honest, puffy cumulus wisps of moisture floating around in the sky. The truth is the “Cloud” is a marketing term made up to sell a service (note: the quotation marks around “Cloud” were to delineate that marketing term. From here on out, “Cloud” will be written sans quotation). That service, the Cloud, is computing and storage capacity as a service. In human terms, it is a system of delivering computing and storage needs via three types of computing services: Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS). Although this is true, for most people Cloud can be broken down into two categories, Public or Private.



The Public Cloud is the ability to use services that do not reside on your local computer. Examples are Spotify, Netflix, Dropbox and Gmail. All of those services allow a consumer to access the Cloud by storing their information in a datacenter and streaming that information to their own personal computer. The Public Cloud is called “public” because although it allows individuals to stream movies from Netflix or have an email account via Gmail, data is maintained in a public infrastructure.

Think of this infrastructure as a scalable apartment building. In an apartment building (Public Cloud) there are separate apartments all full of different tenants (multitenancy). Each tenant uses the space allotted to him or her for their own personal use without every encroaching on another tenant’s space. The same concept applies in the Public Cloud however unlike a real apartment building, if you need more storage capacity you pay for more storage capacity. The ability to pay for only what you use and need is called scalability. Within a Public Cloud infrastructure, users pay for what they need and never encroach on another tenant. In the Private Cloud, scalability still applies however the infrastructure is different.

In a Private Cloud, as the name suggests, you are no longer part of a multitenancy infrastructure. Rather you are the only tenant. In terms of scalability, because the infrastructure is different, you now pay for an allotted and determined storage capacity as opposed to paying for how much space you need at that moment. Simply put the benefit of a Private Cloud isn’t in scalability, it’s in security.

Within the Private Cloud because you are alone in your infrastructure, you don’t have to worry about what other tenants are doing that could potentially cause a breakdown in security. Rather your main concern is illegal access into your Cloud from the outside world. A good hosting company will deploy stringent firewalls across a their Private Cloud to make sure nothing illegal takes place.

The other large added benefit of a Private Cloud is VPN. VPN, or Virtual Private Network, allows a company to make a direct connection with their hosting company or between two offices to share vital information, make repairs, fix glitches etc. A VPN is the ultimate in Cloud Computing because it allows for a secure private direct connection to share sensitive data without having to worry about the data being compromised.

In terms of who uses both options, private consumers tend to use the Public Cloud while companies with vital information tend to use the Private Cloud. There is also a combination of both, appropriately titled the Hybrid Cloud.

The Hybrid Cloud is an infrastructure in which a company provides and manages some resources in-house and manages other externally. Whatever these resources are, legacy Nortel phone system, a hosted exchange system, an internal APP development system, is up the company. By using a Hybrid Cloud, companies can take advantage of the scalability features of the Public Cloud while at the same time avoiding opening themselves up to third-party security scares.

Now that you know what the Cloud is and the different types of Cloud infrastructure, the next question we have to answer is, how does the Cloud affect me as a consumer, as someone working for a business (Ex. a mobile app developer) and as a business?

The answer to that question to come in next week’s blog post.

• Clouducation 101: Consumers, Web Developers & Businesses
• Clouducation 101