Cloud computing in general can be portrayed as a synonym for distributed computing over a network, with the ability to run a program or application on many connected computers at the same time. It specifically refers to a computing hardware machine or group of computing hardware machines commonly referred as a server connected through acommunication network such as the Internet, an intranet, a local area network (LAN) or wide area network (WAN) and individual users or user who have permission to access the server can use the server's processing power for their individual computing needs like to run an application, store data or any other computing need. Therefore, instead of using a personal computer every-time to run the application, the individual can now run the application from anywhere in the world, as the server provides the processing power to the application and the server is also connected to a network via internet or other connection platforms to be accessed from anywhere. All this has become possible due to increasing computer processing power available to humankind with decrease in cost as stated in Moore's law.In common usage, the term "the cloud" is essentially a metaphor for the Internet. Marketers have further popularized the phrase "in the cloud" to refer to software, platforms and infrastructure that are sold "as a service", i.e. remotely through the Internet. Typically, the seller has actual energy-consuming servers which host products and services from a remote location, so end-users don't have to; they can simply log on to the network without installing anything. The major models of cloud computing service are known as software as a service, platform as a service, and infrastructure as a service. These cloud services may be offered in a public, private or hybrid network. Google, Amazon, IBM, Oracle Cloud, Rackspace, Salesforce, Zoho and Microsoft Azure are some well-known cloud vendors. Network-based services, which appear to be provided by real server hardware and are in fact served up by virtual hardware simulated by software running on one or more real machines, are often called cloud computing. Such virtual servers do not physically exist and can therefore be moved around and scaled up or down on the fly without affecting the end user, somewhat like a cloud becoming larger or smaller without being a physical object.
From the above explanation of cloud computing , there are many benefits that we can take from cloud computing , namely :
1. Scalability , ie cloud computing we can increase our storage capacity without having to purchase additional equipment , such as hard drives , etc. . We simply add the capacity provided by the cloud computing service providers .
2. Accessibility , ie we can access data whenever and wherever we are , as long as we are connected to the Internet , making it easier for us to access the data when important .
3. Security , we can be assured that the data security of its cloud computing service provider , so for IT based company , the data can be stored securely in the cloud computing provider . It also reduces the cost required to secure corporate data .
4. Creation , ie the user can do / develop their creations or projects without having to submit their projects directly to the company , but the user can send it through the cloud computing service providers .
5. Anxiety , when a natural disaster strikes our proprietary data stored safely in the cloud even though we damaged hard drive or gadget
Here is how the data storage and replication of data on the use of cloud computing technology . With Cloud Computing is no longer a local computer should run the heavy computational work required to run the application , no need to install a software package for every computer , we only perform the installation of the operating system on application . Computer networks that make up the cloud ( Internet ) handles them instead . This server will be running all applications ranging from e - mail , word processing , to complex data analysis programs . When users access the cloud ( internet ) for a popular website , many things can happen . Users of Internet Protocol ( IP ) for example can be used to determine where the user is located ( geolocation ) . Domain Name System ( DNS ) services can then redirect the user to a server cluster that is close to the users so that the site can be accessed quickly and in their local language . The user is not logged into the server , but they login to their services using a session id or cookie that has been obtained is stored in their browser . What users see in the browser usually comes from a web server . Webservers run the software and interface presents the user with the means used to collect orders or instructions from the user ( click , type, upload , etc. ) These commands are then interpreted by webservers or processed by the application server . Information is then stored in or retrieved from a database server or file server and the user is then presented with a page that has been updated . The data is synchronized across multiple servers around the world for global access quickly and also to prevent data loss.
Characteristic of Cloud Computing :
1 . On Demand Self Service ( yourself when self-service is needed )
Users can order and manage services without human interaction with the service provider , for example by using a , a web portal and interface management . Procurement of services and equipment as well as related resources occur automatically on providers
2 . Broad Network Access ( access to large networks )
Services available are connected via broadband networks , especially for adequately accessible through the Internet , either using a thin client , thick clien , or other media such as smartphones .
3 . Resource Pooling (resource fused )
Cloud service providers provide services through resources that are grouped in one or multiple locations of data centers consisting of a number of servers with multi - tenant mechanism . This mechanism allows a multi- tenant computing resource is shared by several users , where those resources either in the form of physical or virtual, can be allocated dynamically to the needs of users / customers on demand . Thus , customers do not need to know how and where the demand for computing resources met by the service providers . Importantly , all requests can be fulfilled . The computing resources include storage , memory , processor , network band , the virtual machine .
4 . The Rapid Elasticity ( rapid elasticity )
Computing capacity that can be provided rapidly and elastically supplied , be it in the form of the addition or reduction of the required capacity .
5 . Measured Service ( measurement )
Available cloud resources should be managed and optimized its use , with a measurement system that can measure the usage of each computing resource use ( storage , memory , processor , bandwidth , and user activity , etc. ) . Thus , the amount of resources used can be measured in a transparent manner which will be the basis for the user to pay for the cost of using the service .
The relative security of cloud computing services is a contentious issue that may be delaying its adoption. Physical control of the Private Cloud equipment is more secure than having the equipment off site and under someone else's control. Physical control and the ability to visually inspect data links and access ports is required in order to ensure data links are not compromised. Issues barring the adoption of cloud computing are due in large part to the private and public sectors' unease surrounding the external management of security-based services. It is the very nature of cloud computing-based services, private or public, that promote external management of provided services. This delivers great incentive to cloud computing service providers to prioritize building and maintaining strong management of secure services.[146] Security issues have been categorised into sensitive data access, data segregation, privacy, bug exploitation, recovery, accountability, malicious insiders, management console security, account control, and multi-tenancy issues. Solutions to various cloud security issues vary, from cryptography, particularly public key infrastructure (PKI), to use of multiple cloud providers, standardisation of APIs, and improving virtual machine support and legal support
When talking about cloud computing system , the system is divided into two sections : the front end and back end . They are connected to each other through a network , usually the Internet . The front end is the side the computer user (user ) , or the client ( the client ) , see . The back is the " cloud " part of the system . The front end includes the client computer ( or computer network ) and the application is required to access the cloud computing system .
Not all cloud computing systems have the same user interface . Services such as Web - based e - mail program utilizes existing Web browsers such as Internet Explorer or Firefox . Other systems have unique applications that provide network access to clients . At the back end of the system are the various computers , servers and data storage systems that create the " cloud " of computing services . In theory , a cloud computer system can include almost any computer program you can imagine , from the data processing to video games . Typically , each application will have its own dedicated server . cloud computing servers centrally manage the system , monitoring traffic and client demands to ensure everything runs smoothly . These systems follow a set of rules called protocols and uses a special kind of software called middleware . Middleware network allows computers to communicate with each other . Mostly, the server is not running at full capacity . That means no processing power unused waste products . It will require a way . This technique is called server virtualization . By maximizing the output from each server , server virtualization reduces the need for the machine to work .
