Date Added: May 2010
Despite the rapid development in the field of cloud computing, security is still one of the major hurdles to cloud computing adoption. Most cloud services e.g. Amazon EC2 is offered at low cost without much protection to users. At the other end of the spectrum, highly secured cloud services e.g. Google "Government Cloud" are offered at much higher cost by using isolated hardware, facility, and administrators with security clearance. This paper explores the "Middle Ground", where users can still share physical hardware resource, but user networks are isolated and accesses are controlled in the way similar to that in enterprise networks.