“The 2010 Handbook of Application Delivery: The Emergence of the Application Delivery 2.0 Era” by Dr. Jim Metzler is a treasure trove, one of the more valuable works on the subject today.

At well over a hundred pages there’s far too much to adequately summarize here, but he does a particularly good job quickly summarizing cloud computing’s issues:

As was the case with virtualization, relative to the Application Delivery 2.0 era, Metzler finds, cloud computing “is a double-edged sword as it both presents challenges and solutions.” He notes one “almost comical aspect of cloud computing” is that there is “a high degree of disagreement in the IT industry around the precise definition of what is meant by cloud computing.”

In spite of that confusion, the goal of cloud computing is quite clear -- “to enable IT organizations to achieve an order of magnitude improvement in the cost effective, elastic provisioning of IT services that are good enough.”

The phrase “good enough,” Metzler says, “refers in part to the fact that the SLAs that are associated with public cloud computing services such as Salerforce.com or Amazon‘s Simple Storage System are generally very weak.”

For example, he notes, “most of the SLAs don‘t contain a goal for the performance of the service. In addition, it is common to access these services over the Internet and nobody provides an SLA for the availability of performance of the Internet. As such, organizations that use these services do so with the implicit understanding that if the level of service they experience is not sufficient, their only recourse is to change providers.”

Relative to the provisioning of IT services, Metzler writes, historically “it has taken IT organizations several weeks or months from the time when someone first makes a request for a new server to the time when that server is in production. In the last few years many IT organizations have somewhat streamlined the process of deploying new resources. However, in the traditional IT environment in which IT resources have not been virtualized, the time to deploy new resources is still measured in weeks if not longer. This is in sharp contrast to a public cloud computing environment where the time it takes to acquire new IT resources from a cloud computing service provider is measured in seconds or minutes.”