Cloud computing

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1 Cloud computing FOCUS: server consolidation Virtualization allows to have: • Hardware independence of the software, • High flexibility, • The operative system and the applications can be handed as a "single entity" Consolidation means migrating from physical to virtual machines, servers are connected one another so it is possible to: • Perform live migration, which is moving one server to another physical architecture without switching it off, thus making the system more scalable; • Automatically balance the workloads, without the machines feeling the difference; • Protect the machines from hardware or system failures, as if a physical machine fails the other continue running, so the virtual machines do not need to be stopped even if they could be slowed down. It leads to a higher hardware utilization, it allows different operative systems to run on the same hardware and to continue to use legacy software (Linux applications on Linux, Windows on Windows, …) as the applications are independent from the hardware. Cloud computing is a model in which resources as CPU and storage are provided as general utilities that can be leased and released by users through the Internet in an on-demand fashion. Cloud computing (DEF) It is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources, as network, servers, storage, applications and services that can be rapidly provisioned and released with minimal management effort or service provider interaction. 1. Cloud application (software as a service): the user accesses resources which are provided through the internet without needing to install or know anything. 2. Cloud software environment (platform as a service): the users are application developers, they are supplied with a…