Wednesday, February 11, 2009

Private and Public Clouds

Last year I wrote a post about emerging Cloud utilities and I discussed some scenarios briefly where the pure "everything in the cloud" model is unlikely for many companies in the next decade or two. Will everything move to the Cloud? Doubt it.

As many IT professionals already know, the integration challenge is already tough enough for applications hosted inside organisations. This new SaaS model just adds to the complexity. Granted, SaaS or Cloud solutions also create huge advantages but the industry needs to seriously consider this integration challenge.

Integration is not just about integrating web based applications using something like OpenID but also considering hybrid models where some solutions will be provided using SaaS and others will still be hosted internally.

It seems Cisco is also thinking about this hybrid world and the integration challenges associated with it. Private Clouds are Real - Internetworking for the Cloud.

Cloud computing architectures, whether public or private, or frankly ‘virtually private’ (private cloud extending into public infrastructure with enterprise control and trust established) will need a set of networking systems and architectures.
...Cloud Internetworking is about enabling the Inter-Cloud, the federation of cloud computing systems between enterprise and provider and one provider to the next. Workload becomes portable, and the Cloud Internetwork embraces this portability and ensures that the elements of trust and control don’t break or disappear with the advent of mobile workloads. Additionally, the Cloud Internetwork ensures that as workloads move they are still reachable via the most efficient path.

Back in December I was musing about the network risk associated with Cloud computing services. These risks haven't changed and they will have to be addressed by both the providers and the customers.

...the risk to the provided SaaS service is now in the network. If connectivity to the network is lost (from any node), those at that node have no service. I know this is stating the obvious but the point here is the types of services being provided - they're starting to become more mission critical. This means the accessibility requirements go up. It's not good enough for an organisation to have a five 9's up time from the SaaS provider if they can't access it.

For critical services the configuration of the network at each node now needs to be considered.

Finally, I ask the question at the start of this piece "will everything move to the Cloud?". I doubt it. There are many reasons why I think this but one of the most compelling is that it doesn't make sense for some applications to run entirely in the Cloud.

I still think that some of the analyst commentary and services being provided are similar to those we had around the .com boom. At that time, everything was being turned into a .com, even when it made absolutely no sense. I fear the same is happening with Cloud computing. Some services don't make sense in the Cloud, or at least the way they are currently being considered.

I think it makes total sense for documents, spreadsheets, presentations etc (i.e. the data) to be stored out in the Cloud securely. I'm not as convinced that running all the apps themselves in the Cloud is such a good idea. A hybrid model will be best in some cases - even though this will be a more complicated service to create.

I talk about this more here.

I'll leave you with this quote by Douglas Gourlay from Cisco:

...the Cloud Internetwork ensures that enterprises have choices, providers have markets, and infrastructure interoperates.