Iaas / saas

Infrastructure as a Service (IAAS) / Software as a Service (SaaS)
In an IaaS model, a third-party provider hosts hardware, software, servers, storage and other infrastructure components on behalf of its users. IaaS providers also host users' applications and handle tasks including system maintenance, backup and resiliency planning. 
The following are salient examples of how IaaS can be utilized by enterprise:

  • Enterprise infrastructure; by internal business networks, such as private clouds and virtual local area networks, which utilize pooled server and networking resources and in which a business can store their data and run the applications they need to operate day-to-day. Expanding businesses can scale their infrastructure in accordance with their growth whilst private clouds (accessible only by the business itself) can protect the storage and transfer of the sensitive data that some businesses are required to handle.
  • Cloud hosting; the hosting of websites on virtual servers which are founded upon pooled resources from underlying physical servers. A website hosted in the cloud, for example, can benefit from the redundancy provided by a vast network of physical servers and on demand scalability to deal with unexpected demands placed on the website.
  • Virtual Data Centers (VDC);  a virtualized network of interconnected virtual servers which can be used to offer enhanced cloud hosting capabilities, enterprise IT infrastructure or to integrate all of these operations within either a private or public cloud implementation.

 A typical Infrastructure as a Service offering can deliver the following features and benefits:

  • Scalability; resource is available as and when the client needs it and, therefore, there are no delays in expanding capacity or the wastage of unused capacity
  • No investment in hardware; the underlying physical hardware that supports an IaaS service is set up and maintained by the cloud provider, saving the time and cost of doing so on the client side
  • Utility style costing; the service can be accessed on demand and the client only pays for the resource that they actually use
  • Location independence; the service can usually be accessed from any location as long as there is an internet connection and the security protocol of the cloud allows it
  • Physical security of data center locations; services available through a public cloud, or private clouds hosted externally with the cloud provider, benefit from the physical security afforded to the servers which are hosted within a data center
  • No single point of failure; if one server or network switch, for example, were to fail, the broader service would be unaffected due to the remaining multitude of hardware resources and redundancy configurations.  For many services if one entire data center were to go offline, never mind one server, the IaaS service could still run successfully.
No additional hardware costs; the processing power required to run the applications is supplied by the cloud provider.
  • No initial setup costs; applications are ready to use once the user subscribes.
  • Pay for what you use; if a piece of software is only needed for a limited period then it is only paid for over that period and subscriptions can usually be halted at any time.
  • Usage is scalable; if a user decides they need more storage or additional services, for example, then they can access these on demand without needing to install new software or hardware.
  • Updates are automated; whenever there is an update it is available online to existing customers, often free of charge. No new software will be required as it often is with other types of applications and the updates will usually be deployed automatically by the cloud provider.
  • Cross device compatibility; SaaS applications can be accessed via any internet enabled device, which makes it ideal for those who use a number of different devices, such as internet enabled phones and tablets, and those who don’t always use the same computer.
  • Accessible from any location; rather than being restricted to installations on individual computers, an application can be accessed from anywhere with an internet enabled device.
  • Applications can be customized and whitelabelled; with some software, customization is available meaning it can be altered to suit the needs and branding of a particular customer.