Mega trends: The convergence of public and private clouds
By Martin May, regional director, Enterasys Networks.
Cloud computing has quickly evolved into an umbrella term, describing a variety of different computing concepts that involve a large number of computers (increasingly mobile devices) that are connected to one another. At the core of all cloud computing applications lies the concept of a converged infrastructure with shared resources and shared services, says Martin May, regional director at Enterasys Networks.
Up to now, the emphasis has been on the 'private cloud', an infrastructure operated for (or by) a single organisation, whether managed internally or by a third party, and hosted internally or externally. The key benefit of a private cloud is recognised as its ability to pool and dynamically allocate IT resources across any number of business units, allowing services to be deployed quickly - and even scaled to meet growing needs.
Implementing a private cloud project demands a significant level of engagement to 'virtualise' the entire business environment. It thus requires organisations to re-evaluate decisions about existing resources and re-examine the health of their underlying network infrastructures.
In contrast to private cloud infrastructures - where hosted services are usually limited to a known number of people (staff and visitors) behind a firewall - the public cloud makes resources available over the Internet to an often undefined audience.
A public cloud's advantages include lower upfront costs as all the costly data centre resources are held by a third-party service provider and delivered to the user 'as a service'. Moreover, cloud service providers generally compete with each other on price, so it is possible to negotiate lower costs for computing services.
Technically, there are very few differences between private and public cloud architectures, with the exception that security considerations are often substantially more challenging when services as well as applications, storage and other resources are made available by a service provider for a public audience with communications effected over a public network.
Nevertheless, it is becoming clear that there are significant benefits to be obtained from both architectures working in concert. Today, one of the most relevant aspects of the development of private and public cloud technologies is their convergence. The converged cloud - or hybrid cloud - represents an emerging technology that's rapidly gaining traction in the marketplace as organisations use the public cloud for data storage and archiving, but continue to maintain in-house, private cloud applications and infrastructures for operational activities.
Typically, a hybrid cloud infrastructure is the result of a partnership between the user and public cloud provider(s) in terms of which certain resources are provided - and managed - in-house, and others are provided and managed externally.
Strictly speaking, a hybrid cloud is a composition of at least one private cloud and one or more public clouds. The private cloud element can be an on-premises cloud or a virtual private cloud, located remotely.
Importantly, the hybrid cloud approach allows an organisation to take advantage of the scalability and cost-effectiveness offered by a public cloud without exposing mission-critical applications and data to third-party vulnerabilities.
Because the hybrid cloud should deliver the advantages of public and private clouds in a seamless manner, it promotes the structuring of an agile business in which decisions are made more rapidly and where reactions to marketplace trends and developments are faster.
The challenge facing organisations contemplating hybrid cloud computing is to provide this seamless operation across all platforms, including cloud application programming interfaces (APIs) and hypervisors or virtual machine managers (VMMs).
Is this possible, bearing in mind the complexity with which hybrid clouds are generally associated? The fact is, the legacy IT infrastructures within many organisations have evolved over time to the point where they lack form and present hurdles that only specialists can overcome.
Therefore, before embarking on any cloud-computing endeavour, organisations need to have their infrastructures audited in a bid to gain a clear view of the interdependencies of the different IT services within them.
What's required is a fully rationalised and carefully defined map of all these interdependencies before they are deployed in a hybrid cloud. In this way, users can gain the upper hand in terms of management and enjoy a smooth and trouble-free implementation.
When a hybrid cloud is strategically implemented, organisations can source applications by specific architecture, security requirements and usage to create the best mix of internal and external cloud environments to meet the needs of their application portfolios.
Although some barriers to certain hybrid approaches remain, the majority are well within reach and gaining popularity among enterprises of all sizes.