The different skills you need for public and private clouds

QA's Matt Bishop compares and contrasts the different skills needed for organisations looking to move to public or private clouds

It's easy to see the benefits of cloud computing, and moving to the cloud is often an easy decision to make - at least, in theory. In practice, of course, it's not just a single decision; there are a huge number of other questions that also need to be answered. One of those questions is which deployment model to go for: public or private cloud?

Crucially, the difference between public and private clouds is all to do with tenancy: a public cloud has many users, while a private cloud is used by a single organisation. It has nothing to do with access (you can run private services in a public cloud, or vice versa) or with ownership (a third party can own and operate your private cloud for you).

There will be many factors that influence an organisation's choice between public and private clouds; in this article, I want to focus on the single issue of the different skills that are required for a successful transition.

Business skills: planning and negotiating

It is obviously important to plan ahead and understand the likely scope of the changes involved in migrating to the cloud. To do this, you will need skillsets such as project management, specification of requirements, budgeting, and (if third parties are going to be involved) contract negotiation. However, there are important differences between migrating to public and private clouds.

In public clouds, it's possible to start small and grow, re-architecting as you go along, because the physical infrastructure that you use is drawn from a huge common multi-tenanted pool and is all available without any up-front commitment. So extensive advance planning is less essential for the public cloud; it's possible to work out at least some of the details as you go along. Obviously, that doesn't mean you can get away with no planning at all - security, auditing and governance (to pick a few things off the top of my head) will require considerable planning - but you don't need to have a complete three-year migration plan set in stone on day one. Contract negotiation is also less of an issue; while you'll need to negotiate on the non-technical details, such as terms of service and support, the technical details of the services are normally offered on a take it or leave it basis, with no scope for negotiation.

In a private cloud, by contrast, the infrastructure and services are provisioned solely for your use. New services will arrive more slowly, if at all, and the scale of the service provided will be less flexible. The upshot of this is that you will need to spend more time planning, scoping out your requirements, deciding exactly which services and applications will migrate to the cloud and which will not, and so forth. If your private cloud is to be managed by a third party, you will need the skills to negotiate both the technical and the non-technical details of the contract.

Technical skills: building and using clouds

In any cloud platform, public or private, you will need deep knowledge of the services that are offered by the cloud platform to its end users. In a private cloud, there will typically be fewer, more basic services (often just core compute, network and storage), and these will evolve very slowly, if at all. Public cloud providers compete to offer a huge range of services, which can change and grow very frequently. This makes it harder to keep your skills current in the public cloud (although the benefits can be considerable if you do).

For any cloud, there is a division of responsibility between the user and the operator of the cloud. As a user of a managed private cloud or a public cloud, you will have limited visibility of what's happening on the operator's side of that division, and it's essential to understand how to work with that and still remain secure. Your provider should be able to offer detailed recommendations on (for example) how to go about establishing compliance with PCI DSS while using their services.

For a self-managed private cloud, your organisation sits on both sides of this division. You need user skills but also operator skills, probably in two different teams of people. The operator skills roughly correspond to those skills needed to run a data centre: procuring and managing hardware, configuring the physical environment, installing and configuring the selected virtualisation platform (for example, VMware vCloud or Microsoft Cloud Platform System), securing and patching, monitoring and auditing, and so on.

Training and skills are just one factor in a cloud migration strategy, but an important one. Particularly for a private cloud deployment, having appropriately skilled teams in place at the very beginning of the project can make the difference between success and failure.

Matt Bishop is principal technologist, cloud services at IT training provider QA

Computing and QA have partnered to launch their cloud computing training campaign, which aims to raise awareness of cloud computing and explore how companies can gain the maximum business benefits