Cloud computing is the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer.
Cloud computing is comparable to grid computing and it is working based on multitenancy (Multitenancy is a reference to the mode of operation of software where multiple independent instances of one or multiple applications operate in a shared environment.)
Everybody has a different definition of cloud computing based on their view. Actually Cloud computing has different meaning based on their usage.let’s see some of user’s needs and how cloud computing can help their needs .
End user needs → Needs a application to do their job more efficiently .
Developer → Needs a platform which provide efficient way to develop applications.
Businessman → Needs a good infrastructure that handles all user needs ie application.
Above three users views are fulfilled by cloud computing as one.so cloud computing itself gives application(SAAS) , Platform(IAAS), Infrastructure(IAAS).
Cloud computing is good in following Characteristics :
- Scalability → Cloud computing offers organizations, both big and small, the opportunity to scale their computing resources whenever they deem it necessary. This is done by either increasing or decreasing the required resources, meaning you're not paying for resources which you are not utilizing.
- Secure → Cloud computing security is the set of control-based technologies and policies designed to adhere to regulatory compliance rules and protect information, data applications and infrastructure associated with cloud computing use.
- Reliable → These include redundancy of power, Internet connection, cooling systems, fire suppression systems, servers, storage, and security systems.
- Device and location independence → Enable users to access systems using a web browser regardless of their location or what device they use (e.g., PC, mobile phone). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.
- Maintenance → Cloud computing applications is easier, because they do not need to be installed on each user's computer and can be accessed from different places.
Multitenancy → Enables sharing of resources and costs across a large pool of users thus allowing for:
- centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)
- peak-load capacity increases (users need not engineer for highest possible load-levels)
- utilization and efficiency improvements for systems that are often only 10–20% utilized.
- Performance → monitored, and consistent and loosely coupled architectures are constructed using web services as the system interface.
- Productivity → Productivity may be increased when multiple users can work on the same data simultaneously, rather than waiting for it to be saved and emailed. Time may be saved as information does not need to be re-entered when fields are matched, nor do users need to install application software upgrades to their computer.