From "Cloud Computing" on Wikipedia...
Some have come to criticize the term [Cloud Computing] as being either too unspecific or even misleading. CEO Larry Ellison of Oracle Corporation asserts that cloud computing is "everything that we already do", claiming that the company could simply "change the wording on some of our ads" to deploy their cloud-based services. Forrester Research VP Frank Gillett questions the very nature of and motivation behind the push for cloud computing, describing what he calls "cloud washing" in the industry whereby companies relabel their products as cloud computing resulting in a lot of marketing innovation on top of real innovation. GNU's Richard Stallman insists that the industry will only use the model to deliver services at ever increasing rates over proprietary systems, otherwise likening it to a "marketing hype campaign".
I agree with the critics. I've never really paid much mind when the term "cloud" or one of its nebulous variants is tossed out during marketing discussions, but I do understand the benefit of being able to just say "cloud" from a marketing perspective. And that said, I could tell you that OnSIP is in “the cloud.” I could tell you OnSIP is both a cloud platform and a cloud application. I could tell you that the My.OnSIP user interface is a cloud client. I could tell you OnSIP proudly takes part in the intercloud community and utilizes the latest in public-private hybrid combined cloud technology and engineering. To the best of my knowledge, that’s all true.
I could also provide you with a little concrete technical detail about the infrastructure OnSIP is currently built on.
The OnSIP production system is currently physically located in two carrier hotels (collocation centers) - 60 Hudson St in New York City and 1 Wilshire in Los Angeles. We lease space, power and cooling from datacenter operators at these locations. We do not own or operate our own datacenters. We do own and operate our own redundant physical networks and systems with hardware from Dell, Cisco and Juniper. We are not a telephone company. We have no direct connectivity to the PSTN. We are customers of, and have dedicated IP interconnections with, a variety of CLECs who get calls to/from the PSTN on our behalf.
We operate separate IP networks for realtime (i.e. voice and other RTP) traffic and non-realtime (i.e. web) traffic. For realtime traffic, we have paid peering agreements with almost all “tier 1” internet carriers. We lease physical cross-connects to these carriers and always operate these interconnects at congestion free levels (an over-provisioning approach to QoS). We have separate transit connections for non-realtime traffic. The software we utilize is predominately an integrated mixture of code we have written in-house and customized open source. We run it primarily on CentOS and utilize KVM for virtualization. While we are active and enthusiastic participants in the open source community, we do also make use of commercial software. That’s all true.