Infrastructure as a Service has invaded the data centre, and public clouds are battling it out with private clouds and hybrid clouds. Lesley Meall, FSN contributing editor looks at the differences between these approaches, and considers the pros and cons.
There is a storm brewing in the world of cloud computing. “The term ‘cloud’ has been hi-jacked by everyone on the planet now,” quips Thorsten von Eicken, chief technology officer and founder of RightScale, a specialist in cloud computing management, and he is concerned about the hype. “There is a power struggle going on,” he adds, particularly in the area of information technology (hardware and software) infrastructure: “All sorts of vendors are trying to co-opt the term, and if you are doing anything in the technology industry at the moment it needs to feature the word ‘cloud’.” He seems to have a point.
The SPI model that is Software as a Service, Platform as a Service and Infrastructure as a Service, started with the relatively simple notion of data, applications and hardware being accessed remotely, through a third-party provider. But in the time-honoured tradition of the IT industry, SPI is spawning an ever-increasing, and confusing, alphabet soup of cloud-related abbreviations and offerings. This is currently most apparent in the data centre, where the generic ‘public cloud’ that we all thought we understood, has been joined by more mysterious ‘private clouds’ and ‘hybrid clouds’.
“To date cloud computing has by and large been in the realm of public clouds,” says Eicken, but this is changing fast. “Over the last few months there has been a sustained buzz,” he reports, “and now people are saying ‘I want a cloud in my own data centre’.” So, if you thought that a key component of cloud computing was the fact that you, the enterprise, didn’t need to host and run the infrastructure, think again. Purists may decry private clouds as an oxymoron, but now that they have entered the marketing-speak of vendors such as Cisco, Dell and IBM, cloud computing has effectively been redefined.
The public cloud offers a shared computing infrastructure that anyone can access and connect to via the internet; Amazon EC2 still makes computing capacity available for rental, by the hour, through its über cloud. But Infrastructure as a Service is now evolving to include flexible networks (based on the public cloud model), that are built and managed, internally, for the use of the enterprise’s users, and these are being described as ‘private clouds’ and ‘internal clouds’. “There is huge interest among our clients in being able to learn from ‘the cloud’,” says Tom Bittman, a senior analyst with Gartner, and the research giant sees the future of internal IT as “very much a private cloud” (of which more, later).
Apply a healthy dose of scepticism
At Appirio, the specialist in products and services for on-demand solutions, Ryan Nichols, takes a more cynical view. “Most of the companies talking about private clouds are making a lot of money out of selling you data centres,” asserts the VP of product management, who sees the private cloud as little more than “a data centre by another name”. Nichols doesn’t believe that an internal resource can deliver the low capital expenditure, reduced admin, or (potentially) infinite capacity and scalability of the public cloud infrastructure. “A private cloud wont offer businesses the incremental improvements they gain when they stop operating their own data centre,” he states.
So what are the benefits of building and operating your own private cloud? Eicken suggests the following: reduced security concerns, close proximity to non-cloud data centre resources, control of hardware resources and their provisioning, better utilisation of legacy resources, and the ability to satisfy regulatory requirements without the cooperation and support of the cloud provider- and RightScale is gearing up to support both public and private clouds. But while the trend towards (server and storage) virtualisation in the data centre can make the move to a ‘private cloud’ seem evolutionary, it is a mistake to underestimate just how big an undertaking it is.
Organisations that want to deliver cloud-like services within the business, by creating a cloud-like environments in their own data centres, will need to take on many of the costs and responsibilities they could avoid by utilising external cloud resources. To build an internal cloud, an enterprise will need to supplement its data centre systems and processes with various new layers of technology, ranging from virtualisation management, through cloud APIs, to charge-back systems – and more. This could look a lot like a list of reasons for taking the public cloud approach instead, but perspective is everything.
Look at clouds from both sides
Because the business benefits offered by public and private clouds tend to be mutually exclusive, a ‘hybrid cloud’ approach has much to recommend it. “The benefits of the public cloud revolve around cost, and duplicating them internally is possible only on a really large scale,” says Eicken, “while the benefits of the private cloud revolve around control.” So although he admits to initially being sceptical of the private cloud concept, he now appreciates why businesses want to get the best of both worlds. “It makes sense for enterprises to gravitate towards a hybrid model,” he adds.
At Gartner, Bittman also sees the enterprise approach evolving into one where the intrinsic strengths of public and private clouds are exploited, in turn, as and when it becomes appropriate. “Some services are not destined for the cloud, and should evolve in a very different direction, and some services should be converted to a public cloud offering soon,” he says, adding: “Organisations need to determine the right strategy for each service.” With the support of the right technology, it’s an approach that could give organisations the flexibility to opt for the variation, or variations of ‘cloud computing’ that best meet their requirements.
“In some scenarios you may want development and testing to run on servers in the public cloud, then run the system internally,” says Eicken, perhaps for regulatory or information security reasons. Developing in private and deploying in public is another option. “Testing in the same type of environment as you will use in production is a good reason to set up an internal cloud,” he says, even if the deployment will eventually be in the public cloud for connectivity, redundancy, or scalability reasons. Some organisations want to be able to switch between the private and public clouds as and when it is convenient or necessary, using a single management system.
This hybrid cloud Nirvana is not yet universally available (if it ever will be), for a variety of reasons. These range from access control challenges and software licensing constraints, through cost and complexity, to bandwidth bottlenecks and regulatory restrictions. “I believe that enterprises will spend more money building private cloud computing services over the next three years than buying services from cloud computing providers,” says Bittman, so it may only be a matter of time. Meanwhile, Eicken the realist recommends a tentative approach to public and private cloud projects in the data centre.
“At RightScale we struggle with unrealistic expectations,” he says, explaining: “Not everything you can do in the cloud should be done in the cloud, and not everything you want to do is achievable today.” But he suggests that now is a very good time to start with small non-critical projecs. “You can experiment, learn about the business benefits, and gain an understanding of the what the problems are,” he says, while keeping a watching brief, so that future projects can be planned for six or twelve months down the line as they enter the realms of possibility. “We are only just taking the first steps down the road toward the promise of hybrid cloud architectures,” he says, but as he adds: “There are great business benefits to be had, even today.”
