Aaron writes: > ... > I would agree that the simplest description of a public cloud is what > you mention - "one that allows anyone to sign up(either freely or > paid) to access the resources provided". Like amazon EC2, etc. > > The hybrid model mentioned is what I would describe as a private cloud > that when needed can pull in or access resources of a public cloud. > There do exists VCL provisioning modules in development that can > request resources from EC2 and IBM's cloud. Xianqing Yu is working > on a JIRA issue for interacting with an IBM cloud > https://issues.apache.org/jira/browse/VCL-457 as an example.
I agree - but would like to add a non-technological dimension to the definition. We normally call the VCL a "private cloud" because that is how we and most (all?) universities use it - and it could be a "hybrid cloud" if the provisioning modules were running. However, I think the real distinction is in how the VCL (or other cloud) is *managed.* The VCL can be run to allow anyone/everyone to log in access the resources provided. This isn't done because of resource limitations, license limitations, etc. - all real reasons but not technological limitations. Therefore I'll even quibble with the above definition of a "hybrid cloud" because the user interface is into a private cloud, and the user ideally isn't even aware of where the cloud resources live and so just sees it as a private cloud. Bottom line: private/hybrid/public distinctions have both technological and administrative meanings. --henry schaffer
