Questions On Cloud Computing Architectures

As we learned in previous weeks, cloud computing services have three major different cloud architectures for different demanding customers. The three different architectures are Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS). For the words of the name, we can see the obvious differences among these three architectures, which they provide different cloud services based on their specific cloud architectures. What are the differences among these three cloud services? What are the responsibilities for the cloud services providers? What are the responsibilities for the customers? The following will discuss about these questions.

Amazon: Amazon Elastic Compute Cloud (Amazon EC2) is a web service that provides resizable compute capacity in the cloud. It is designed to make web-scale computing easier for developers. Amazon EC2 is simple web service interface allows you to obtain and configure capacity with minimal friction. It provides you with complete control of your computing resources and lets you run on Amazon’s proven computing environment. Amazon EC2 reduces the time required to obtain and boot new server instances to minutes, allowing you to quickly scale capacity, both up and down, as your computing requirements

Cloud computing offers services to users based on on-demand self-service, broad network access, measured service, resource pooling and rapid elasticity; These characteristics promise a faster time for implementation, lower cost, superior scalability and a better end user satisfaction. These services are delivered in models known as Software As A service (SaaS), Platform As A Service (PAAS), and Infrastructure As A Service (IAAS). The first layer which is the Software As A service (SaaS) is the layer in which software applications are delivered to end users. Below is the Platform As A Service (PAAS) layer which offers a platform on which applications can be developed. The lowest layer is the Infrastructure As A Service (IAAS) layer, in this layer the physical servers and network infrastructure is offered as a service. These services can be deployed throughout the internet (Public Cloud Computing), on the intranet infrastructure, (Private Cloud Computing), in a shared community of private networks (Community Cloud Computing), or a hybrid of both (Hybrid Cloud Computing). The service deployment models are [8]:

SaaS – Software as a Service – Users on the service are given access to the application’s software and databases, cloud providers manage the infrastructure and platforms that run the application. “On demand”.

A cloud computing system, can be divided into two sections: the front end and the back end. They connect to each other through a network, usually the Internet. The front end is the side the computer user, or client, sees. The back end is the "cloud" section of the system. The front end includes the client's computer (or computer network) and the application required to access the cloud computing system.

PaaS can be well-defined as a computing platform that permits the making of web applications rapidly and simply and without the difficulty of purchasing and preserving the software and infrastructure beneath it. PaaS is equivalent to SaaS excluding that, somewhat than buying software distributed over the web, it is a platform for the making of software, carried over the web. As with most cloud services, PaaS is made on top of virtualization knowledge. Industries can demand incomes as they want them, mounting as mandate cultivates, rather than capitalizing in hardware with dismissed capitals.

This coordinates elements supporting high adaptability and multi-occupancy. In addition, distributed computing minimizes the capital consumption. This methodology is gadget and client area free. As indicated by the not at all like sorts of administrations offered, distributed computing can be considered to comprise of three layers. IaaS or Infrastructure as a Service (IaaS) is the most minimal layer that gives fundamental base bolster administration. PaaS - the Platform as a Service (PaaS) layer is the center layer, which offers stage arranged administrations, other than giving the earth to facilitating client 's applications. SaaS - Software as a Service (SaaS) is the highest layer which includes a complete application offered as administration on interest. SaaS guarantees that the complete applications are facilitated on the web and clients use them. The installment is being made on a pay-per-use model. It takes out the need to introduce and run the application on the client 's nearby PC, in this manner mitigating the client 's weight for programming consideration. In SaaS, there is the Divided Cloud and Convergence intelligibility instrument whereby each information thing has either the "Read Lock" or "Compose Lock". Two sorts of servers are utilized by SaaS: the Main Consistence Server (MCS) and Domain Consistence Server (DCS). Reserve rationality is

Amazon provides cloud utility computing, also known as on-demand computing when they introduced their services Simple Storage Service (S3) and Elastic Compute Cloud (EC2). With these two services, Amazon provides a pay-as-you-go model of computing capacity to businesses that want to pay only for what they use. Amazon can generate more revenue from other businesses by offering excess capacity to those that need it.

Amazon Elastic Compute Cloud (Amazon EC2) offers a computing environment of processor, memory, and preconfigured software. It provides a scalable within a pay-as-you- go plan. It has decreased the time required to obtain, and it provides a bit of a new server instances to minutes. It permits the user to a faster scale capacity. Amazon EC2 can conversion the economics of the computing by permitting the user to pay for a capacity usage of the services. Amazon EC2 offers the creators a software tool to form a failure resilient application.

In 1999, Salesforce.com became the first web service to deliver applications and software over the internet. This service eventually led the way to the cloud. In 2006, Amazon unveiled its own cloud computing platform called Amazon Web Services or AWS. The Amazon Web Service now provides online services to other websites and client-side applications and powers hundreds of thousands of startups and larger companies in over 1190 countries worldwide (Fee, 2013). After Web 2.0 was developed in 2009, other companies started their own cloud services. The cloud is used by consumers daily on many different outlets such as: social media applications like Instagram and Pinterest, Google Apps, Apple iCloud, Microsoft OneDrive, and much more. Now, any time you store information without using up your smartphone or your computer’s internal data, you are storing information on the cloud. The National Institute of Standards and Technology (NIST) defines cloud computing as a computing storage system that provides on-demand network access for multiple users and can allocate storage to users to keep up with changes in their needs (Nelson, Phillips, Steuart, 2015). The cloud has three levels: Software as a service (SaaS), Platform as a service (PaaS), and Infrastructure as a service (IaaS). With Software as a service, applications are delivered by the internet. An example of this would be Google Docs, where data is stored in the cloud and files

There are a variety of definitions that are associated with cloud computing. However, the importance of how the technology is transforming business models greatly exceeds any specific definition. There are three components that are usually cited in any definition of cloud computing (Gabrielsson, Hubertsson, Mas, & Skog, 2010). The most commonly known component is the Software as a Service (SaaS). This allows organizations and consumers the ability to use software on demand and be billed for the usage on a per use basis.

Software as a Service (SaaS), sometimes referred to as "on- demand software" is a software delivery model in which software and associated data are hosted on the cloud. SaaS is typically accessed via a web browser and is paid on a subscription basis, monthly or yearly as per requirement.

There are many advantages and disadvantages when considering Software as a Service, Infrastructure as a Service and Platform as a Service such as updates and maintenance, private or public clouds and the type of service SaaS, PaaS, or IaaS. First, updates and maintenance: it is imperative that the company look at the maintenance services provided by the cloud host and how often updates and maintenance are accomplished. Second, private or public clouds: management must determine which is more important a cheaper service or a safer service. On the one hand, a private cloud offers the capability of distributing its allotted resources amongst its users in a private setting

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In order to fully understand what software as a service is and how it can benefit the user you must first have an understanding of how this type of computing is accomplished. I think it is important to understand what is meant by the “Cloud”. Cloud computing or software as a service, put simply is when software is ran over the Internet and accessed by an Internet browser (Schneier, 2009).