CLOUD COMPUTING 2 Chapitre From having been highly centralized, information systems have become highly decentralized. With the Internet, all computer machines and digital devices can exchange information. In cloud computing or " the cloud " , computer resources are shared among many users and billed following consumption, as public utilities are. Cloud computing proposes a pay- as- go model. Large cloud services have functions distributed over many machines in several locations and the computer resources are reallocated according to demand. The same server can be used during European business hours for specific applications e.g., emails and be used for processing other data during American business hours. A cloud system may rely on peer- to- peer networks in which peer computers pool their resources and communicate in a decentralized manner; an algorithm balancing the workload between the peers. GRAMMAR POINT Rappel des différences entre for et during: - For indique vraiment la durée en anglais et répond à la question how long? I watched TV for two hours last night. - During répond à la question when? My father fell asleep during the show. Dropbox and Google Drive are two cloud applications: files are stored somewhere and can be retrieved from anywhere. For a company, moving to cloud signifies going from a model based on investment to a model based on rental. Furthermore, the company is no longer responsible for the upgrades and maintenance which are outsourced and included in the fees. 211