A User's Guide to the Cloud

In the world of computing, “the cloud” is a term that refers to one or more various types of computing resources that are available for access through a network, such as the Internet. These remotely hosted computing resources include, but are not limited to, remote storage, software run on remote systems, shared computer processing power and anywhere/anytime access to applications ranging from databases to phone services. Cloud computing is often used in order to save money by outsourcing information technology management tasks to another company, or service provider. The core concepts behind the cloud are shared services, infrastructure, and resources, all of which are centrally managed by a single company. The concept of cloud computing is similar to grid computing and mainframes, and in some ways even a public utility.

What Is The Cloud?

The cloud is most commonly referred to as a remote service where users entrust their applications, computing capacity, and even their data. Users can store their data in the cloud, as well as access word processing and graphical applications there, among other things. The cloud is a collection of computers and storage systems networked to form a sort of super computer cluster which is centrally managed. This means that users simply access the cloud and use the software and storage space that is provided. They do not have to install, configure or maintain their own hardware, because all of this is done for them by the cloud service provider.

The cloud manifests itself in one of four ways: Software as a Service (SaaS), Platform as a Service (PaaS), Infrastructure as a Service (IaaS), and Network as a Service (NaaS). Examples of SaaS include things that are most visible to small businesses and end users, like webmail services, virtual desktops, cloud gaming, and PBX voice service. PaaS includes less visible features like databases and web servers, and other features which are primarily useful to software programmers and web developers. IaaS features, such as virtual machines, load balancers and virtual servers, cater to the needs of system administrators who must configure operating systems for a given project. NaaS involves the use of network bandwidth in the cloud. Bandwidth-on-demand is a popular service that relies on the Network as a Service model.

Infoworld: What Cloud Computing Really Means
Pawprint at Cornell University: Cloud Computing: What Is It?
Emory University: Cloud Computing: Defining and Describing an Emerging Phenomenon
UC Berkeley – Above the Clouds: A Berkeley View of Cloud Computing
US Computer Emergency Readiness Team: The Basics of Cloud Computing
Microsoft: What is Infrastructure as a Service?

History of Cloud Computing

The origins of cloud computing date back to the use of mainframe computers by universities and corporations back in the 1950s. During that time, users primarily worked with computers called dumb terminals, which relayed data from mainframes but lacked any computing ability of their own. This led to the sharing of mainframe computing power by multiple users, which became known as time-sharing. A computer scientist named John McCarthy said of this technology that computing resources might one day be used as a public utility. This technology eventually evolved to a point in the 1990s when the emerging Internet enabled companies to develop Virtual Private Networks, or VPNs. VPNs enabled networks to operate securely inside of other networks, which was a primary component of what would become cloud computing. The term “Cloud Computing” was first coined by Ramnath Chellappa, a professor at Emory University, but telecommunications companies had been using the cloud symbol since around 1994. The cloud symbol was originally meant to show where outside data entered the jurisdiction of the service provider, or the point where the service provider was responsible for protecting the data. Amazon was the first major corporation to use cloud computing in its modern form, in the years after the dotcom crash. Their system was called Amazon Web Services, and it was the first system to fulfill John McCarthy’s prediction of computers being used as a public utility. Soon after, other companies such as Google and IBM began pushing cloud computing into the mainstream.

Forbes Magazine: The History and Future of Cloud Computing
Computer Weekly: A History of Cloud Computing

The Purpose of Cloud Computing

The purpose of cloud computing is three-fold. One, it helps companies with large amount of unused computing resources to put their systems to full use. This enables them to pay for the equipment they own and must maintain. Two, it helps businesses outsource the costs of information technology (IT) management to companies that are better suited to the task. This is especially beneficial for companies that are not in the business of IT management. This includes doctor’s offices, the entertainment industry, banks, and the like. Finally, another purpose of cloud computing is to free end users from being tethered to powerful but heavy and immobile personal computers. Through cloud computing, workers can handle their tasks and manage their data with nothing more than a tablet computer or a cell phone, working through a remote system hosted “in the cloud.”

Vox: The Economics of Cloud Computing
WP Carey School of Business – Cloud Computing: The Evolution of Software-as-a-Service
 Washington University in St. Louis: Mobile Cloud Computing

Accessing and Using the Cloud

Users can be anywhere in the world when they access the cloud. All they need is a web-capable computing device and access to the Internet. To access the cloud one may need to use encryption, and users will almost always need their login credentials. If the user is accessing a VPN, they will also need a VPN access client. Some users prefer to keep their data on their computing devices, while others prefer to keep it with the applications that are hosted in the cloud. Cloud computing gives users the flexibility to do both, leaving their choices limited to the whims of their employers or the limitations of their computing devices, which may or may not have the ability to store their data. When their data is stored in the cloud, they can access it from anywhere in the world, no matter what device they use. In the cloud, one’s data and private applications may be accessible by other users, including the cloud provider, which is why it is sometimes preferable to protect their information with strong encryption. This is especially important for companies such as doctor’s offices, which are regulated by the Health Insurance Portability and Accountability Act (HIPAA).

Boston University Information Security – How to Safely Store your Data in the Cloud
Yale University – Data Management in the Cloud: Limitations and Opportunities (PDF)

Benefits of Cloud Computing

Cloud computing enables software to be accessible from anywhere in the world. For instance, a user in Japan can make use of software applications or data in a location in America, without ever having to download the actual software. Businesses can deploy applications or data into the cloud and strictly control who accesses them. By outsourcing the network and hardware management tasks to a cloud provider, the company is also saving the large up-front costs involved in building their own large-scale systems. Even businesses that choose to develop their own private in-house cloud can save money by deploying workers in the field with cheaper, lower-powered computers such as tablets, or even cell phones. Moreover, users of cloud services financially benefit from the cloud’s on-demand business model, which means that they only pay for the resources they actually use. Instead of paying for computer servers to be turned on and using electricity but not doing anything, they only pay for the time they spend working in the cloud. These cost reductions help to lower the barrier to entry in various industries, thus evening the playing field between small and large businesses. One of the most common benefits of the cloud for end users includes web mail, by which people access email stored by and managed on computers in the cloud. Among the more dramatic benefits of cloud computing is the promise of reduced energy usage, and thus also greenhouse gas emissions.

Carnegie Melon University – Software Engineering Institute: Basics About Cloud Computing (PDF)
Phys.org: Virtual Servers Begin to Intrigue Smaller Businesses
Open Data Center Alliance: Cloud Computing
UCSD – Cloud Computing for Developing World Economies: Crucial for Global Connectedness