Cloudonomics: The Business Value of Cloud Computing, + Website

Availability of Networked Resources

The cloud does not inherently increase availability; in fact, if used unwisely, it can reduce availability.

If, as we’ve discussed, clouds provide services or resources over a network, presumably accessed by some sort of local endpoint, such as enterprise data center resources or a smartphone, tablet, or sensor, instead of one point of failure, there can be many.

For a desktop application to function, your PC must be working, and the app must be working. But for a cloud-based application accessed by your PC to work, your PC must be working, the browser must be working, your Internet access must be working, the cloud must be working, and the cloud-based app must be working. And, in turn, for your Internet access to work, your wireless card must work, your Wi-Fi router must work, it must be configured properly, your Internet service provider must be up, the cloud data center’s network access must be functioning, and so forth.

Unfortunately, all components are imperfect. As a rule, the more imperfect resources we try to string together, the less likely the whole thing is to work. So, merely moving a portion of work to the cloud may have lots of benefits in terms of elasticity and total cost reduction but, in and of itself, could hinder availability. Used correctly, however, the cloud can enhance availability.