What is the difference between "cloud" and "grid" computing?:
-Grid computing is a grouping of computers using common software to share processing load. Cloud computing is is similar in that it shares a load across infrastructure but different in that it does not require a common software package, the infrastructure "lives" on the internet and is presented as a server or series of servers to the end user. For example a computer "grid" could include an application installed on an individuals PC that is computing and phoning home, versus a computer "cloud" is entirely internet based.
What are the advantages of the cloud?:
-Presumably the reduction in actual IT resource costs. Specifically, the cloud vendor takes care of backups, procurement, monitoring, hardware failures basically all the day to day IT stuff outside of the application itself. This should allow for smaller IT departments since these functions are handled. It does not replace the need for a knowledgeable person to set up special configuration within servers and install and manage applications. The cloud will also be available anywhere with the big pipes of the cloud vendor supporting it.
What are the disadvantages of the cloud?:
-Still need folks to set up and maintain the applications even if not the day to day tasks. Pricing is dynamic (at least for EC2) depending on what platform you require and bandwidth usage. Security... Can you safely store regulated data (HIPAA, 21cfrPart11, Sarbanes Oxley) in the cloud? Can you reliably audit access to the cloud even from technicians at the cloud vendor? If your data is all in the cloud you may need big pipes of your own to access it.
Thoughts?:
I would probably be willing to experiment with cloud computing for non-mission critical, non-security sensitive (from a regulatory perspective) applications. I wouldn't consider moving my core infrastructure to the cloud at the moment but i will certainly be watching.
Questions?:
-How do you span single sign on/integrated authentication across locally installed and cloud installed servers? Particularly when you are paying per bit on the wire.
Looks like i'm not the only one with these concerns:
ReplyDeletehttp://www.pcworld.com/article/158615/tips_for_safe_cloud_storage.html
Another interesting article on cloud computing: http://arstechnica.com/business/news/2009/02/into-the-cloud-a-conversation-with-russ-daniels-part-ii.ars
ReplyDeleteThe author seems a little confused between information state and cloud computing at the beginning of the article (the cloud doesn't magically take care of transferring state information, like where you last left a video in an airplane) but the actual interview with Russ Daniels is good.
This did bring a thought to mind though. How does the cloud react under load. For instance, the computing resources of an online business may get hit very hard around the holidays and remain relatively idle the rest of the year. But what happens when that is magnified across hundreds or thousands of online businesses? And what happens if the cloud vendor is itself an online business (Amazon comes to mind) who get priority? The obvious solution would seem to be isolating resources but that is counter to the idea of sharing in the cloud.
Also, what if you are using the cloud to supplement IT infrastructure and are expecting consistent performance day to day. Do you need to anticipate what your neighbor might be doing in order to ensure your own application performance?