Cloud computing is still in its infancy, with many providers offering different and incompatible services in different ways. There are many different ways of implementing cloud solutions – public, private, bare-metal, hybrid and all sorts of overlaps in the way the same things are described by different users and providers. Over time things will mature – all the applications running in cloud will be written for cloud and users will be able to move computing workload seamlessly between providers. But not just yet.
In general, applications that work well in cloud today are ones where communications traffic is light and not exceptionally time critical, where security is important but not critical, where a new application can be written especially for the cloud implementation and where fast scalability provides a worthwhile user benefit.
The easiest applications to migrate to cloud are those with low complexity and low user traffic. Examples are general office desktop computing, and many providers, from the giant Microsoft downwards, now offer desktop software which will run remotely on their own virtualised servers in their own data centres rather than on the user’s servers on the user’s premises. Most organisations will have many similar applications, such as ERP systems, CRM systems, HR systems and all the general IT requirements of a modern organisation. All of these can be migrated relatively painlessly to the cloud and all the suppliers of such software are busily working on cloud offerings to their existing customer bases. Mostly, these are applications where the user base is well defined, where there is a high level of predictability and where the application is a cost to the organisation, rather than one that generates revenue.
More complex applications, such as storage and analytics, can also work well in remotely hosted cloud applications. The data traffic may be heavy for storage but is not usually time critical. Similarly for analytics, where intermittently needed scalable compute power is the requirement.
Applications with variable and unpredictable workloads also work well in cloud implementations. Examples are email systems, web servers and e-commerce systems. Again, all the suppliers of such systems are working to offer their own cloud implementations of their products. In these types of applications, the users are often scattered world-wide, the workload is chaotic and highly elastic and they are often associated with revenue generation.
Although cloud is continuously evolving, there are some areas that most organisations would steer away from putting in the cloud today. The biggest concern for all cloud users was originally security, and it remains security, in spite of strenuous efforts by the cloud and software vendors. If the organisation’s mission critical computing and corporate intellectual property is on site, behind a corporate firewall, with known and trusted staff in control of it, management feels the risk of theft or unauthorised disclosure is less than if it is in another location, under the control of unknown staff who may or may not put the company’s key interests first. If something goes wrong, the company’s own staff will work through the night to put it right (with the benign encouragement of their bosses), whereas management may not trust an outside provider to deliver the same commitment. Perhaps those fears are not justified today, but every survey shows they remain real.
Another area requiring much care is anything involving real time data traffic, such as voice telephony. Whilst it is certainly possible to run voice over the open public internet (Skype does it all the time), running it to a guaranteed and consistent level of quality is quite different. In such cases, users are better avoiding cloud and sticking with known specialised data centres with the appropriate range of carriers and experience, or going to a specialised provider of hosted communications, who will certainly be located in such a facility.
Cloud is unquestionably the way computing is going and will continue to go. But some computing, IT and communications applications are more suited to cloud implementation than others. Choosing what to implement first, and what will work well in practice, requires skill and forethought, but will be rewarded with a steady, reliable migration, easier maintenance and lower operating costs. For many organisations, there may never be a full migration to cloud, as mission critical and security critical applications remain in house and other run remotely in the facilities of cloud providers.