A development of the concept of cloud hosting for enterprise customers is the Virtual Data Center (VDC). This employs a virtualised network of servers in the cloud which can be used to host all of a business’s IT operations including its websites.
The more obvious examples of cloud hosting involve the use of public cloud models – that is hosting websites on virtual servers which pull resource from the same pool as other publicly available virtual servers and use the same public networks to transmit the data; data which is physically stored on the underlying shared servers which form the cloud resource. These public clouds will include some security measures to ensure that data is kept private and would suffice for most website installations. However, where security and privacy is more of a concern, businesses can turn towards cloud hosting in private clouds as an alternative – that is clouds which use ring-fenced resources (servers, networks etc), whether located on site or with the cloud provider.
A typical cloud hosting offering can deliver the following features and benefits:
- Reliability; rather than being hosted on one single instance of a physical server the website is hosted on a virtual partition which draws its resources, such as disk space, from an extensive network of underlying physical servers. If one server goes offline, it dilutes the level of resource available to the cloud a little but will have no effect on the availability of the website whose virtual server will continue to pull resource from the remaining network of servers. Some cloud platforms could even survive an entire data centre going offline as the pooled cloud resource is drawn from multiple data centers in different locations to spread the risk.
- Physical Security; the underlying physical servers are still housed within data centers and so benefit from the security measures that those facilities implement to prevent people accessing or disrupting them on-site
- Scalability and Flexibility; resource is available in real time on demand and not limited to the physical constraints/capacity of one server. If a client’s site demands extra resource from its hosting platform due to a spike in visitor traffic or the implementation of new functionality, the resource is accessed seamlessly. Even when using a private cloud model the service can often be allowed to ‘burst’ to access resources from the public cloud for non-sensitive processing if there are surges in activity on the site.
- Utility style costing; the client only pays for what they actually use. The resource is available for spikes in demand but there is no wasted capacity remaining unused when demand is lower.
- Responsive load balancing; load balancing is software based and therefore can be instantly scalable to respond to changing demands