Public cloud is almost known to be hosted on the internet through thoese who are named "Cloud Service Provider", and this can be in different forms either infrastructure or platform or services.
-- SaaS (Salesforce.com’s CRM, Google Apps, Zoho CRM etc.)
-- PaaS (Salesforce.com’s Force.com platform, Google App Engine)
-- IaaS(Amazon EC2, )
Private cloud is almost known to be hosted on premises or your organization through IaaS frameworks listed below, and this can be in different forms either infrastructure or platform or services as well.
-- SaaS (I can think of this in terms of your intranet accessed apps that conform to the SaaS model, however this is not a common use case, as there are some differences between these apps and the subscription-babsed known SaaS apps)
-- PaaS (AppScale, 10gen).
-- IaaS(Ecalyptus, OpenNebula, OpenECP, Nimbus etc.)
Mohamed El-Refaey wrote: Private cloud is almost known to be hosted on premises or your organization through IaaS frameworks listed below, and this can be in different forms either infrastructure or platform or services as well.
Does the organization for which the private cloud is used manages this infrastructure?
mohamed sanaullah wrote:
Mohamed El-Refaey wrote:Yes, they can have a skilled IT admin to manage them.
So how is this different from the usual Grid of servers?
The difference comes from the cloud characteristics and benefits:
- reduced number of servers AKA using virtualized environment to have more services with low number of virtual machines.
- dynamically provisioning these servers.
- you can setup a simple UI request form for other employee to request a machine for a certain period of time for a certain purpose.
- the ease of management of your physical servers that host the cloud nodes and its associated virtual instances.
- and much more ...but this is fair enough to distinguish between the classical model of provisioning grid of servers and between setup a cloud or virtual environment.
I hope I would be able to explain it well for you ...
mohamed sanaullah wrote:Thanks a lot for the explanation. Things are clear now
one more thing you should be aware of, cloud won't replace IT admins, the point is that those admins should cope with such new skills related to the cloud environment in order to cope with its frequent improvements and changes every day, as the advance in the cloud is going with the rock speed!