Are there any truly disconnectable web solutions available for cloud computing?

Question

Cloud computing offers a lot of up-side (I currently favour Google’s App Engine), but have encountered resistance from customers who are worried that basing their business platform on the Internet (as opposed to internet servers) would risk staff productivity during temporary internet outages. Are there any solutions available that involve caching/replicating data to an Intranet server, or web based solutions that are truly “disconnectable” such that corporate users could operate during Internet outages? Do you know of any macro design patterns or components or solutions that fit this bill?

Answer 1

Eucalyptus seems to be the go-to software for open source private clouds at the moment. It's compatible with Amazon's cloud services.

Answer 2

This is highly dependant on your application needs and design.

If you have a truly distributed architecture, it would seem that you can run a node in your client's office as well as in the cloud provider's VM infrastructure. You will have to deal with all the disconnected operation conflict resolution issues that have always been present in multiple-master configurations.

If you are going to the "cloud", it would seem the better solution is to have multiple outbound network connections, and host your application in more than one provider's cloud infrastructure.

The macro design pattern is "no single point of failure".