Cloud Computing

What is Cloud Computing?

Over the past few years, the word ‘cloud’ has become the most interesting word to the people who are associated with computing or who have a keen wish to learn computer science. The origin of cloud computing can be traced back to the 1950s. Most of the people find it very confusing because everyone has got a different definition of the phrase ‘cloud computing’.

Cloud computing relies on sharing computing resource instead of having local or private servers. In simple words, it means to store and access your data over a network connection, which is usually the internet, instead of your computer’s hard disk. We can say that when you store your data or programs on the internet, it can be referred to as cloud computing.  It is just contrasting to the fact that when you store your data on your computer’s hard disk, it is called local storage or local computing.

What is a Cloud?

The word cloud is just a metaphor for the internet. In other words, the cloud is a network of servers. Our data is stored in the cloud. Almost every one of us uses a cloud at least once a day. If we check our email, it means we are using a cloud. Whenever we use Gmail, Yahoo mail, facebook, dropbox, google docs, we are directly using their cloud. The cloud can be considered a very large memory space where we can store our data. For example, whenever we upload a photo on Facebook, it remains there until we delete it. That photo is not stored on our computer because if we delete that same photo from our computer, it will still exist on Facebook. Have you ever thought where are all the photos uploaded on facebook stored? It is the facebook cloud where our photos are stored. Most of us store our important files in Dropbox so that we do not have to carry them everywhere we go. In this case, also, we are storing our files in a cloud. The same goes for our emails. We can check our emails from any computer in any corner of the world. As the emails are stored in the cloud, our mailbox looks the same on every computer. It does not depend on where we are opening our email. The common thing in all the examples stated above is the internet. We need an internet connection to perform all this. This is the reason why the word cloud is used as a metaphor for the internet.

Types of Clouds

Primarily, there are four different types of cloud models. They are as follows:

• Public Cloud: In the public cloud, the services are provided to the general public by the service provider. The owners of the resources and the infrastructure offer the access to their services over the internet. The customers neither have the control of infrastructure nor is the infrastructure visible to them. These clouds are very large scale and they offer the greatest efficiency in the field of shared resources. The characteristics of a public cloud are:
  • The standardized workload for applications
  • Testing and developing of application code can be done
  • Capacity can be incremented
  • Best choice for the partnership project
• Private Cloud: This type of cloud is dedicated to a particular organization. They operate within a firewall. This type of cloud is more secure and controlled. The private cloud has two variations.
  • On-Premise Private Cloud: This type of cloud is hosted by the organization which is using the cloud. It is used for the application in which the organization needs the complete configuration and control of the infrastructure.
  • Externally Hosted Private Cloud: This type of cloud is used by an organization but it is hosted by a third party which specializes in the infrastructure of the cloud. This third party is usually the service provider.  The service provider should guarantee the full privacy of the organization. The characteristics of a private cloud are:
    • Efficient cloud with data sovereignty
    • Consistent services
    • More server capacity
• Community Cloud: The community cloud provides the cloud service to many organizations. The cloud is hosted by all the organization in a combined way or by some other third party, that is, they can be on premise or off premise.
• Hybrid Cloud: The hybrid cloud is a combination of two or more clouds. It increases the flexibility of computing.

Origin of Cloud Computing

The roots of cloud computing can be traced back to the 1950’s. At that time, many organizations started to use mainframe computers. But they were so costly and no one fully used the large storage capacity and processing power offered by them at that time that the company could not afford a mainframe system for each and every employee. So they used a practice called time sharing. This allowed different users to use one mainframe through different terminals. These terminals had no internal capabilities of processing of their own. This technology proved to be very beneficial and economic. Then, in 1969, an American computer scientist, J.C.R Licklider created the ARPANET (Advanced Research Program Agency Network).  It is now called the predecessor of the internet. He wanted everyone in the world to be interconnected.  He wanted that everyone should be able to use data from any site in any part of the world. This is what cloud computing helps us to do. Later, in between the 1970s and 1990s, there occurred many other major developments in the field of cloud computing.  The first version of the VM operating system was released by IBM in 1972. It permitted two different computing environments to be installed in the same physical environment. Many other companies started to provide virtualized private network connections in the 1990s. It is said that the word cloud computing was first used by the executives at the Compaq computers somewhere in 1996.

The evolution of cloud computing from then and now included the following phases:

• Grid Computing: In this type of computing, many different computer resources from different physical location reach a common goal. In simple language, multiple computer resources which are in the same network are applied to the same problem to reach a common goal. SETI, that is, Search for Extra-Terrestrial Intelligence, is a well-known example of grid computing.
• Utility Computing: In utility computing, computer resources are provided on demand and the users have to pay per usage.  In this, the service provider owns the computer infrastructure and resources, only the access is provided to the user on the rental basis. This type of computing is very flexible and economic. Cloud computing and grid computing are based on the principle of utility computing.
• SaaS:  It is the abbreviation used for “Software as a Service”.  It is also referred to as on “demand software”. In SaaS, the application or the software is made available to the users by the vendor over a network. This network is usually the internet.

The next phase was cloud computing itself.

Characteristics of Cloud Computing

The main characteristics of cloud computing are listed below.

• Rapid Elasticity: The cloud is flexible to suit the immediate needs. Features, resources and the users can be added or removed quickly. The system is elastic enough so that extra needs can be met, and then the system can return back to its original state. The cloud is infinite. The user has to purchase the required amount.
• Measured Service: The infrastructure and resources are managed by the service providers. This helps in the allocation of resources and the billing. All the services can be measured and have transparent usage for both the user and the provider.
• On-demand Service: The consumers can use the service when they need it at any place and at any time.
• Network Access: The resources provided by the service provider are available on the internet and can be accessed by any type of the user who knows the standard usage mechanism. The resources can be accessed from any platform ranging from desktops to mobile phones.
• Resource Pooling:  The resources or the computing power is efficiently distributed between the users as per their requirements. The resources are assigned and reassigned as per the changing needs of the user.

Advantages of Cloud Computing

• Cost Efficient: It has helped companies to save on the licensing fees and also eliminate the overhead charges. The cloud is available at a less price than other traditional approaches. There are options like pay as you go, and one-time payment.
• Unlimited Storage: The cloud offers unlimited storage capacity which is not offered by physical memory devices. Therefore, if you are using a cloud u need not worry about running out storage space.
• Backup and Recovery: The data stored on the cloud is much easier to backup and recover than the data stored on a physical memory device. The service providers usually handle the recovery process on their own.
• Automatic Software Integration: The software integration usually occurs automatically in a cloud. No additional efforts are required to customize and integrate the application.
• Ease of Access: After registering on the cloud, the information saved in the cloud can be accessed from anywhere and at any time.
• Quick Deployment: Once you opt for cloud computing, it will only take a short span of time for the entire system to be fully functional. The time will depend on the type of technology.

Disadvantages of Cloud Computing

• Security: When you upload your data or programs in a cloud, you are giving it to a third party which is the service provider. The third party may leak out the information. You have to be completely sure before saving your private and confidential data on a cloud. There is no surety of security on the internet. The data is always at a risk.
• Vulnerability: The data stored on the cloud is more prone to external threats and hacks. The data can be easily leaked from the cloud.
• Technical Problems: the technology is prone to technical issues. When the server is down due to a technical issue, the data stored on the cloud cannot be accessed by the user.

Conclusion
Everything has pros and cons, so does cloud computing. But despite the disadvantages, it still has great potential for the future. It will grow even more in the future and will overcome its disadvantages. Even now, if we use it properly, cloud computing is beneficial.