cloud hosting vs. managed hosting [closed]

Question

It seems the hype about cloud computing cannot be avoided, but the actual transition to that new platform is subject to many discussions...

From a Theoretical viewpoint, the following can be said:

Cloud:

• architectural change (you might not install anything you want)
• learning curve (because of the above)
• no failover (since failure is taken care of)
• granular cost (pay per Ghz or Gbyte)
• instantaneous scalability (not so instantaneous, but at least transparent?) ? lower latency

Managed:

• failover (depends on provider)
• manual scalability (requires maintenance)
• static cost (you pay the package , whether you use it fully or not)
• lower cost (for entry- packages only)
• data ownership ( you do )
• liberty ( you do ) ? lower latency ( depends on provider)

Assuming the above is correct or not; Nevertheless, a logical position is "it depends.." .. on the application itself. Now comes the hidden question: how would you profile your j2ee app to determine if it is a candidate to cloud or not; knowing that it is

• a quite big app in number of services/ functions (i.e.; servlets)
• relies on a complex database (ie. num. tables)
• doesn't need much media resources, mostly text based

Answer 1

"Now comes the hidden question: how would you profile your j2ee app to determine if it is a candidate to cloud or not; knowing that it is"

As an aside, make that the Explicit question. Make it the TITLE of this question. Put it in the beginning of the question. If possible, delete all of your assumptions, and focus on the question.

Here's what we do.

1. Call some vendors for your "cloud" or "managed service" arrangement. Not too many. One or two of each.

2. Ask them what they support. More importantly, what they don't support.

3. Then, given a short list of features that aren't supported, look at your code for those features. If they don't support things you need, you have some architecture work to do. Or cross them off your preferred vendor list.

4. For good vendors, write a pilot contract that gives you free (or cheap) access for a few months to install and test. If it doesn't work, you haven't paid much.

"But why go through the expense of trying to host it when it may not work?"

What expense? You can spend months "studying" your code. Or you can try to host it. Usually, the "try to host it" will turn up an answer within a few days. It's less effort to just do it.