Different Types of Cloud Computing Service Models
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. Read more about some of the core cloud computing benefits for your business. According to a recent survey, the percentage of companies using a public cloud is expected to rise to 51% in 2016. It is estimated that servers shipping to a public cloud will grow at 60% CAGR (Compound Growth Annual Rate), while on-site server spending will be reduced by 8.6% over the next two years. Although cloud computing has evolved over the time it has been majorly divided into three broad service categories: Infrastructure as a Service(IAAS), Platform as a Service (PAAS) and Software as a Service (SAAS) which are broadly discussed below:
Infrastructure as a Service (IAAS)Infrastructure as a Service (IAAS) is a form of cloud computing that provides virtualized computing resources over the internet. In a IAAS model, a third party provider hosts hardware, software, servers, storage and other infrastructure components on the behalf of its users. IAAS providers also host users’ applications and handle tasks including system maintenance backup and resiliency planning. IAAS platforms offer highly scalable resources that can be adjusted on-demand which makes it a well-suited for workloads that are temporary, experimental or change unexpectedly. Other characteristics of IAAS environments include the automation of administrative tasks, dynamic scaling, desktop virtualization and policy based services. Other characteristics of IAAS include the automation of administrative tasks, dynamic scaling, desktop virtualization and policy based services. Technically, the IaaS market has a relatively low barrier of entry, but it may require substantial financial investment in order to build and support the cloud infrastructure. Mature open-source cloud management frameworks like OpenStack are available to everyone, and provide strong a software foundation for companies that want to build their private cloud or become a public cloud provider.
IAAS- Network:There are two major network services offered by public cloud service providers: load balancing and DNS (domain name systems). Load balancing provides a single point of access to multiple servers that run behind it. A load balancer is a network device that distributes network traffic among servers using specific load balancing algorithms. DNS is a hierarchical naming system for computers, or any other naming devices that use IP addressing for network identification – a DNS system associates domain names with IP addresses
Platform as a Service (PAAS)Platform as a Service (PAAS) is a cloud computing model that delivers applications over the internet. In a PAAS model, a cloud provider delivers hardware and software tolls, usually those needed for application development, to its users as a service. A PAAS provider hosts the hardware and software on its own infrastructure. As a result, PAAS frees users from having to install in-house hardware and software to develop or run a new application. PAAS doesn’t replace a business' entire infrastructure but instead a business relies on PAAS providers for key services, such as Java development or application hosting. A PAAS provider, however, supports all the underlying computing and software; users only need to login and start using the platform-usually through a Web browser interface. PAAS providers then charge for that access on a per-use basis or on monthly basis. Some of the main characteristics of PAAS are :
- Scalability and auto-provisioning of the underlying infrastructure.
- Security and redundancy.
- Build and deployment tools for rapid application management and deployment.
- Integration with other infrastructure components such as web services, databases, and LDAP.
- Multi-tenancy, platform service that can be used by many concurrent users.
- Logging, reporting, and code instrumentation.
- Management interfaces and/or API.
Software as a Service (SAAS)Software as a Service(SAAS) is a software distribution model in which applications are hosted by a vendor or service provider and made available to customers over a network, typically the Internet. SAAS has become increasingly prevalent delivery model as underlying technologies that support Web services and service- oriented architecture (SOA) mature and new development approaches, such as Ajax, become popular. SAAS is closely related to the ASP (Application service provider) and on demand computing software delivery models. IDC identifies two slightly different delivery models for SAAS namely the hosted application model and the software development model. Some of the core benefits of using SAAS model are:
- Easier administration.
- automatic updates and patch management.
- compatibility: all users will have the same version of software.
- easier collaboration, for the same reason.
- global accessibility.