Martin P Wilson


Ideas, Innovation, Inspiration, Insight, IT

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Cloud Service Models

Light Clouds KG07031In our previous articles What is Cloud Computing? we covered the principal definition and characteristics of true cloud services. However those characteristics are not enough in themselves to fully describe cloud computing. The National Institute of Standards and Technology (NIST) adds four deployment and three service models to complete the picture.

Cloud computing is essentially an on-demand service based approach to providing computing and information systems resources. It essentially turns IT provision into a utility, similar to telephone or energy, which is paid for on the basis of the services used. It presupposes a service metered in some way.

Essentially services fall into three broad categories and, again, like the characteristics they are not unique to cloud services. However the service based models described are most closely associated with the supply of cloud services; it has only been with the advent of the cloud that they have become a mainstream approach.

Infrastructure as a Service – IaaS

IaaS is essentially the provision of the hardware (servers, storage, network connectivity, …) that is usually a capital expenditure with traditional hosting models. The consumer can then run their choice of operating systems, databases and the applications that are deployed out to the end users. The cloud hosting service supplier maintains the hardware, including technology refreshes, and other components of the infrastructure while the consumer looks after the operating systems and applications and their change management. In the simplest case this might be a cloud server with flexibility as described in the previous article on characteristics.

Platform as a Service – PaaS

Moving up a level or two in the technology stack PaaS takes the IaaS model and then adds provision of and management of the systems software such as operating system, databases, networking and other tools that are provided to the consumer, perhaps for system development. In this case the consumers’ management responsibility is entirely concerned with the provisioning of user applications and any development of such systems if they are not off the shelf packages.

Software as a Service – SaaS

With SaaS the consumer is simply a user of business systems, such as finance, Customer Relationship Management CRM), Data Visualisation or Enterprise Resource Planning (ERP), and has minimal involvement with the provision (once selected) of the business facing applications. The consumer may have a role in configuration of the end-user function of the chosen software but the maintenance of the software such as applying updates to new versions usually lies with the SaaS supplier.

In all three models the consumer organisation will have responsibility for the local user domain with its, and end-user’s, connection to the cloud service provider. This will include the security and provision of network connectivity and the devices used to access the SaaS applications.

Professional Cloud Services

In addition to the three services the UK government adds a fourth component, Professional Cloud Services to its G-cloud catalogue which allows public sector bodies to buy cloud services off the shelf without complex procurement procedures. While not strictly part of the cloud model they form an important element for those making the move to a cloud approach from tradition IT service models. They provide a means of achieving a faster transition or start up for organisations switching their computing to the cloud. The G-cloud catalogue is published and could form a starting point for anybody researching what is available; it should be remembered that it is not complete in that there are major suppliers not represented on the catalogue.

Professional cloud services are essentially the people and skill based resources needed to make the move to the cloud. These can cover everybody from business analysts and consultants to technical staff familiar with the new approach to computing technology. Their use should be on achieving a rapid implementation of the cloud model with a transfer of knowledge and understanding to allow client staff to take it forward into business as usual operations.

Cloud Offerings May Not be What they Seem.

As with any new technology and the cloud generally many services offered in this way are in fact traditional services rebadged as the new approach. They have been “cloudwashed”; old products and services relabelled as the latest thing, again. The purchaser of cloud services needs to be careful of what they are buying; if you are not confident of your technological understanding seek independent advice from sources that are not tied to IT suppliers.

In our next article we will cover the deployment models for cloud computing. It is the aspect that has the most layers of complexity and can be used to create fear, uncertainty and doubt. As a result these are perhaps the least well understood aspects so we will focus on explaining them in practical rather than theoretical terms. In fact, for most organisations, especially SMEs, the picture need not be as complex and confusing as it is often painted.


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Quick Thoughts

Has Military Action Ever Dissuaded Tyrants?

Syria - flagIn his speech before the war in Iraq Tony Blair, the UK Prime Minister, argued that not intervening would send a message that tyrants would feel at liberty to act without consequence. By military action in Iraq, he argued, those who would perpetrate atrocities would think twice. There would not seem to be any evidence, before or since, that would back up that contention.

We now have David Cameron, the current Prime Minister, making essentially the same arguments – do politicians ever learn from history?


Government Spending is not Driver of Growth

Parliament Square London IC02001If more public spending is the only way to create growth then surely governments have become too large a part of the economy? Government is about spending and has little to do with creating wealth.

The best government can do is move wealth from individuals and business to those who serve government.


Capped Bonuses, There May be Trouble Ahead

Politicians do not seem to be good at imagining unintended consequences. The cap on bankers’ bonuses, however popular, may be counter-productive in reducing risk.

Dark Stormy Skys and Beauty Often CoexistIf a smaller proportion of a trader’s income is at risk if a trade goes wrong they may pursue high-risk opportunities to get that big win. If it works they guarantee the full bonus and could also use it to negotiate a higher salary (and bonus) for the following year. If it fails the downside is limited by the capped bonus to a smaller part of overall income. At the end of the day traders are competitive and gamblers at heart so will they be more likely to pursue the big win when their own risk is limited?

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