The cloud computing is the exploitation of computing power or storage remote systems through a network, usually the Internet. As defined by the National Institute of Standards and Technology, cloud computing is an access via a telecommunications network, on-demand and free access, to shared computing resources configurable. So this is a relocation of the IT infrastructure.
What is the cloud computing? It is a new way of consuming the IT. Indeed, the cloud computing is not a technological revolution, but more an economic one.
Traditionally, web and IT users in general invested on computer equipment (software, storage, computing machine ect … ). Today, thanks to cloud computing, the consumer can use the server power made available by a services provider via the Internet.
The cloud computing presents five essentials features for its functioning:
- A free access to resources: the consumer does not need to ask
to the service’s provider an access to the resource, he can immediately access it when he desires it.
- Universal access: Cloud computing is open. That means, any user must be able to access to the cloud from any connected device (computer, tablet, smartphone).
- The pooling of resources: the services provider pools the resources to serve more consumers. The pooling improves the scalability and elasticity and enables to adapt automatically the service to the user’s demands.
- Automatic adaptation to demand: The cloud will be able to automatically manage the user’s needs and adapt quickly and effectively if consumers require more resources, or vice versa.
- The utilisation payment: the service’s provider is able to measure accurately the consumption of different resources, and can charge the customer according to his use.
The services offered by the cloud computing There are three main services offered by cloud computing:
- IaaS: Infrastructure as a service. In this service, only the hardware (servers, storage base, networks), which constitutes the infrastructure, is hosted by the services provider. The consumer uses this service to install applications and operating system on virtual machines made available by the services provider.
- PaaS: Platform as a service. This service provides programming languages, databases and various services to run their applications. The consumers hire the server’s exploitation on which ones the tools are initially placed and controlled by the services provider.
- SaaS: Software as a Service. This service provides applications to the user in the form of a loan service ready for use that does not require maintenance: the services provider regularly makes updates.
There are other cloud computing’s services, including that of: Staas : Storage as a Service is the file’s storage on the servers of the service’s provider. For example: dropbox
The advantages and disadvantages of cloud computing
The advantages
Cloud computing can have several benefits for users. The main advantage resides in the fact that the user will be able to reduce costs. Especially when the company is a start-up that she will not have the funds or the need to invest in hardware allowing it the storage resources. Cloud computing will therefore enable overcoming the traditional computer tools and will enable access to IT tools via Internet. The availability is immediate. In addition, the user will also be able to save money because the customer will not have to take care of equipment’s maintenance provided by the service’s provider. The elasticity of cloud computing allow the user to pay only what it consumes and will automatically adapt to its needs. Finally, cloud computing enables high availability of services. This will depend on service’s provider, but in general, the resources are available most of the time and from any connected object.
Disadvantages
There are several major drawbacks, which result from the use of cloud computing. The safety of services is not flawless; it is quite possible for people with this ability to violate the security establishment by services provider to access the data.For example the case “Celebgate” in which hackers breached the security system of the apple cloud. To the extent that the services provider cannot ensure to the consumer a 100% service availability, the last is dependent on the quality of the network’s provider. The user loses the control over its data, they are “broken” in several often-distributed servers worldwide. He has no other warranty on its data, as the services provider wants to give him contractually. Moreover, as stated earlier, servers can be located abroad and data inside are not protected in the same way that data in France (very protective regime of data). Finally, in the majority of cloud computing’s contracts, nothing is stated about reversibility, it means that when the customer breaks the contract, the services provider is not forced to give back the data to the customer.
In conclusion, the customer must be very careful about the choice of services provider and about the data that he puts on the servers. The best is to have internal servers that are managed by oneself, despite the cost that this entails.
