The answer to what is cloud infrastructure is complicated. Cloud infrastructure is the collection of server hardware, networking gear, storage resources, and software that is needed to build applications that can be accessed by the cloud. In a cloud infrastructure, applications can be accessed remotely using networking services such as wide area networks (WANs), telecom services, and the Internet.
The cloud infrastructure is typically built by service providers or cloud service providers (CSPs) that want to host service in the cloud – which have a wide range of applications such as enterprise software, web hosting, or other IT services that can be accessed remotely, such as a database.
Components of the Cloud Infrastructure
The components of cloud infrastructure are usually broken down into three categories: Computing, networking, and storage. These resources need to work together in order to provide a cloud service. The categories break down as follows:
- Computing: This part of the infrastructure provides the computing power for the cloud service and is usually provided by racks of servers powered by server chips. The servers can be tied together with virtualization software in order to split up the computing power for different clients or services.
- Networking: Routers and switches are used to move data between the computing resources, the storage systems, and the outside world. These might be proprietary data-center switches or white box switches running software-defined networking (SDN) software on commodity server hardware.
- Storage: The cloud service usually requires large amounts of storage resources, which are often pooled and separated from the server hardware in separate racks that might use a combination of hard disks and flash storage. Of the storage systems have their own networking gear and storage software to manage high-performance connectivity with the service.
Managing a Cloud Infrastructure
A cloud infrastructure likely contains very expensive combinations of server, networking, and storage hardware, but the key to making it work altogether is software. This software is often referred to as virtualization software because it is capable of taking all of the hardware pieces and dynamically creating new networks that tie together the virtual resources so that they can be sold to different customers as services. Several different services or clients may be utilizing the same cloud infrastructure at the same time. Various pieces of virtualization software can be used to partition off these virtual networks so that they are secure and discrete.
Many large IT integrators such as Cisco, EMC, HP, IBM , and VMware – as well as many startups – are focused on selling some or all of the pieces of cloud infrastructure and optimizing how they work together. This might include racks of computing power, networking hardware, and storage gear designed to be plugged in as a cloud infrastructure.
Many cloud providers build custom cloud infrastructure themselves. This would include Web hosting providers, Software-as-a-Service (SaaS) providers, social-networking services, and Infrastructure-as-a-Service (IaaS) services. Google and Facebook are high-profile examples, well known for their practice of buying individual technology components, such as service blades or networking chips, and assembling the infrastructure in a custom installation for their own services. Many cloud providers also write their own software code to enable the infrastructure to work together, often using pieces of open source software to do so.