Cloud computing is a big word for over 5 years now and still catches attention of technology decision makers around the world. It's being refered as a way to get rid of all your technology maintenance hores and go straight into simple, affordable software leasing model, where everything works fine, just waiting for you to do the job.
Well, believe me or not, this is all but wrong. So called cloud computing exists from the very beginning of Internet as we know today, however it always had been refered by numerous other, confusing and unsexy terms as hosting, collocation, webmastering etc. For all these years the general principle didn't change much though, since your options are always boiled down to two choices:
-Own by yourself
Depending on the mixutre of the ownership vs. leasing one would like to apply to his IT environment, these two options come in six flavours:
-Pure ownership - you're the man in charge. You have to buy, ship and build your server infrastructure as well as make sure it's wired, connected and cooled properly all the time
-Colocation - your service providers will provide you with a space to put your servers and makes sure they're all connected. You have to take care of the rest
-IaaS - Infrastructure as a Service - your datacentre provider simply leases you all the hardware for a monthly fee and ensures it's up and running
-PaaS - Platfrom as a Service - on top of the infrastructure, your service provider takes care of all operating systems and runtime environments, letting you care only about your applications
-SaaS - Software as a Service - ultimately, your service provider can take care of your applications and provide you with an access to do your business.
The four latter points apply to the whole cloud solutions concept and consitute a first area of confusion. When you rent a virtual server from Amazon are you on the cloud already, or you have to get all-in Salesforce subscription to join the club? On the other hand, if you're the full blown cloud subscriber, does it mean you don't need to worry about electricty for the servers running your rented software?
On August 2011 many IT managers had learnt the hard way, that the cloud myth cannot secure their environments from the nature. That month a lightning strike had knocked down Amazon's EC2 datacentre in Ireland, shutting down for couple of days thousands of websites, ecommerce systems, social portals and web services, including Microsoft's cloud suite Link. Some of the applications, had a business critcial impact, yet many customers could only sit and wait for them to get back online at some point….
How about virtualisation
Virtualisation technology surely lies behind emerge of Cloud term. In nutshell, it enables you to run number of IT systems (virtual machines, appliances etc.) on a single set of hardware (physical server). It's prime advantage, is ability to more efficiently share resources between virtual systems. Thank's to virtualisation you can:
-Run multiple virtual machines on a single physical box
-Assign more or less computing resources (CPU, memory, storage) to virtual systems whenever you wish
-Transfer easily virtual systems from one physical system to another
Thank's to virtualization, some of us stopped worrying about the bare metal boxes we had to maintain to get our apps running and just focused on selecting a correct number or CPUs, amount of memeroy and HDD. Well, that's fine my friend, unless you forgot about reliability and performance which are not tackled by vritualization technology as such.
They virtual environment is only that reliable, as reliable is the bareń metal computer which runs it. If your virtual technology provider don't quite get that, you may find yourself in a big trouble one day (imagine what happens when you've got several virtual servers running on top of a single box). And since the hosting solutions market is a quite tough business today, many service providers will likely look for a way to save on the cost of operations by somehow compromising the reliability and performance.
The true lovers of virtual hosting environments
The virtual environments were a godsend to hosting companies, who now can generate even more revenue out of a single box. Unfortunately, it comes at expense of the performance. The only reason why virtual environments come cheap, is because the cost of hardware running them is split by multiple tenants.
Back in time, hosting company could generate between 20-50 percent of revenue out of the single server, so let's say $10000 worth server, will drive $5000 of revenue. Thanks to virtualization, one can run on top of it even 100 virtual servers averagely priced at $100, what yields at twice as much revenue ($10000) than in the first scenario.
Unfortunately, squeezing hundreds of virtual servers into one box has a potential impact on their performance, since they are all share the same, finite resources. It's OK for some applications, but the others may suffer, especially if they're heavily performance sensitive like websites or commerce systems.
Is it all bad then?
No at all! The cloud (LaaS - Layer as a Service) and virtualization generate tremedous value for companies, but have to be selected and applied consciously. It truly doesn't make any sense for a non-IT company to maintain their IT systems themselves, however they need to be careful to select a reliable and skilled partner to do the job properly. The partner selection process should comprehensively take into account his entire background, partnerships and capabilities to avoid painful surprises in the future.
There is no cloud, it's just someone else's computer
The cloud doesn't exist in a form the IT manager would like it to see. IT systems are complex beasts and the cloud concept only simplifies the naming around them, not their true nature. If you consider your cloud strategy, you might wish to talk to your IT service partner and discuss all possible options. It's likely, you may need couple of partners specialising at delivery of services on their layer of responsibility (in "as a Service" model), unless it has a service delivery strategy end to end.