The concept of cloud computing appears omnipresent in our modern world as we rely on on-demand computing to manage our digital lives across multiple devices – mobiles, tablets, laptops – whilst at home, in the office or on the move. This trio of articles introduces the key component in cloud computing, the servers that underpin each service and provide the computing resource, as well as describing how they provide some of cloud computing’s most notable benefits.
Definitions
Cloud Servers: As mentioned above, can be defined as the servers that are used to provide computing resource for cloud computing. In essence they are servers which are networked together to provide a single pool of computing power which cloud based services can draw resource from.
Cloud Computing: Describes any computing service whereby computing power is provided as a on-demand service via a public network – usually the internet. Broadly cloud services can be categorised using the three following models:
- IaaS – Infrastructure as a Service:
- Pooled physical cloud server and networking resource (without any software platforms). Instead of the user being provided with a single distinct physical server, multiples thereof or shares therein, they are provided with the equivalent resources – disk space, RAM, processing power, bandwidth – drawn from the underlying collective cloud servers. These IaaS platforms can then be configured and used to install the software, frameworks, firmware etc (e.g., solution stacks) needed to provide IT services and build software applications.
- PaaS – Platform as a Service:
- Virtualised software platforms using pooled cloud servers and network resource. These services offer the collective physical resources of IaaS together with the above-mentioned software bundles so that the user has a preconfigured platform on which they can build their IT applications.
- SaaS – Software as a Service:
- Cloud based applications provided using pooled computing resource. This is the most familiar incarnation of cloud computing for most members of the public as it includes any application – such as web based email, cloud storage, online gaming – provided as a service. The applications are built and run in the cloud with end users accessing them via the internet, often without any software downloads necessary.
How Cloud Servers Work
Traditional computing infrastructure models tend to revolve around the idea of single server being used for a particular IT function (e.g., hosting, software applications etc), whether it be that that server is a dedicated server – i.e., for the sole use of that client – or shared across multiple clients. Shared servers may have used the one software/platform installation for all of their IT functions/clients or they may have delivered Virtual Private Servers (VPS) where each client has distinct operating environment which they can configure.
Cloud computing can deliver similar virtualised server environments but they use resource drawn from not one, but a multitude of individual physical cloud servers which are networked together to provide combined pool of server resource. In a sense, it uses a platform that could be considered as a form of clustered hosting whereby the resource demands of an individual client’s IT functions are spread across numerous distinct servers. However, with cloud hosting the resource pool has enough capacity, with sufficient servers, to provide resource which multiple clients can tap into as they need to.
Within the infrastructure of cloud services, cloud servers are networked with what are called hypervisors which are responsible for managing the resource allocation of each cloud server. In other words they control how much resource is pulled from each underlying cloud server when demands are made of the pool of servers, as well as managing the virtualised operating environments which utilise this resource.
