What Is Cloud Computing?
You have probably heard the term “cloud computing” used frequently in recent years, and you might have an idea that it refers to some sort of computing operations that are performed somewhere in cyber space; but like many people perhaps you are quite confused by the real meaning of the phrase. The strange thing is, without even knowing what it means you are extremely likely to be using cloud computing services on a daily basis without realizing it.
If you have an email account with any of the web-based services that are offered free of charge, such as Gmail, Hotmail, or Yahoo! Mail, then you are already acquainted with cloud computing. When you access your Gmail account online and read your email, the data is not stored on your personal computer, but rather in the “cloud” of Google’s email service.
What does “the cloud” mean?
Essentially, the term “the cloud” is just a metaphor for the Internet. It comes from the days when a diagram of a cloud was used to symbolize the phone network. As technology advanced, it was later used in computing network diagrams to demonstrate the infrastructure of how the internet works.
However, in recent years with the introduction of many new services, the term cloud has become somewhat separate, as many companies are describing their services as “cloud-based.” In reality the term internet-based would do just as well, and many more people would understand the concept.
One example of a company creating confusion about “the cloud” was a TV advert for Windows Live, which was shown in several countries around the globe. In the advertisement, a family is seen using the Live Photo Gallery, which is a useful photo management utility. On the advert, a lady who is assumed to be the mother of the family is seen uploading pictures to Windows Live while exclaiming “To the Cloud!”
This had nothing to do with the advert that was extolling the virtues of the photo-editing service, but it shows how companies are using what they consider to be a hip phrase to describe their services.
If you are uploading some pictures to Facebook, and a friend asks you what you are doing, you will probably reply “uploading some photos to Facebook,” or “uploading my pictures to the Internet.” It is extremely unlikely that you would say “I am uploading some photographs to the cloud” although essentially, it has the same meaning – it is just a very abstract way of explaining it, and therefore not a way that is commonly used.
A more correct way to use the term is when companies advertise a service which uses cloud-computing as opposed to a locally hosted solution. Otherwise, it is far more practical to simply use the words “Internet” or “the web”.
In order to easily understand the term, think of cloud computing as when you use software or a service that is based online rather than on your computer.
Cloud computing is available in three types of services. These may be offered alone, or in combination with one another. They are called Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS).
The range of SaaS is very wide. Examples of SaaS are those that deal in content and human resource management, accounting, and many other business related areas.
PaaS offers computing platforms to clients. These include hosting, application development and deployment. PaaS allows users to test and run programs without having the necessary hardware on their local machines.
IaaS is the third type of cloud computing, and like PaaS and SaaS, it delivers software and hardware based on a cloud platform. IaaS allows users to have all the facilities of a hardware platform virtually; they can perform tasks that would usually require the latest technology and equipment without actually owning the physical hardware.
Who can take advantage of Cloud Computing?
As we have seen, individuals who use the Internet for entertainment, research or daily tasks are already likely to be using cloud computing services such as free email providers, Google maps, Picasa photo sharing, and online backup services such as Mozy and Livedrive, where users can upload their files to be downloaded later in the event they have a hard drive malfunction.
However, cloud computing services become very useful when used by larger companies. If you have a company that employs 50 people, who all need to use the same software program to complete a task, you can make your life far easier by using a cloud computing service rather than buying a copy of the software for 50 computers. You would need to update the 50 computers continuously, and if the hardware broke, your employee would likely not be able to continue with his work until his individual computer was fixed. Every time you hired a new person you would have to buy him a copy of the software, or continuously check that you were only running the number of copies that your license allowed. Employees need to email or call each other if they require a file someone else has been working on, which leads to more wasted time.
It is far easier for a company owner to use a cloud computing service, because instead of each staff member having a computer with the software installed, he is just provided with a login to the cloud-based service or app. He can access it from any computer with internet access; he does not need to have the software installed locally on his machine. The files that the workers create when using the service can be stored and shared online, reducing a company’s need for large hard drives.
Therefore, the hardware and software demands on a company are much fewer, thus saving them money. If a worker’s PC malfunctions, he can simply move to a working computer or his personal laptop – no work hours are lost, and his files are safe.
To summarize, cloud computing allows entire businesses and numerous employees to do their work with online rented services, products and tools. The processing work required is done entirely “in the cloud” of the world wide web, and users of the rented services simply need to plug into the service, which is usually done via an internet browser in order to use the service or product.
How does cloud computing work?
A cloud computing service utilizes high capacity networks while allowing companies to buy low cost computers and storage devices. The workload is shifted from local devices to the cloud, and the network of computers and data storage systems that make up the cloud handles the heavy tasks.
A cloud computing system has two sections which are best described as a front end and a back end. These two sections are connected to each other through a network, which is usually the Internet. The front end is what the user of the service sees, and the back end is the part of the system that is in the cloud.
The front end consists of the client’s computer, or network of computers which is used to access the application required to access the cloud computing service. Cloud computing systems use different visual interfaces; for example cloud-based email services can be accessed by a web browser such as Chrome, Firefox or the Internet Explorer, while other systems will have a proprietary application to access the cloud network and service.
The back end of the systems consists of servers, data storage systems and computers that make up the computing cloud. Cloud computing can provide any program you can think of, such as video games, advanced data processing and file sharing. Generally each program will have a dedicated server, rather than making use of a shared server.
One central server will be employed for system administration, which will monitor traffic and make sure client demands are being met. This central server follows specific protocols, and will have software installed that is known a middleware. Middleware lets all the computers in a network “talk” to each other.
Because most of the time servers are running at less than full capacity, there is available processing power that is not being used. A technique called server virtualization is employed which makes each server think it is multiple servers; each running an independent individual operating system. This technique reduces the necessity for hardware, and is used frequently in cloud computing systems.
When a cloud computing company has many clients using their service, there will be a need for plenty of storage space. A large company may need literally hundreds of storage devices to keep all this digital data. A cloud computing service needs to provide a minimum of twice the number of devices actually used for storage, as all data must be stored twice to keep a backup to be accessed immediately should the system malfunction. Therefore, when a breakdown occurs, client’s data can still be accessed, and no vital information is lost. In order that everything always runs smoothly, data must be permanently copied and backed up in cloud computing. Making back up copies of data is known as redundancy, and it is a very important part of cloud computing.