  Cloud Computing holds the potential to eliminate the requirements for setting
up of high-cost computing infrastructure for IT-based solutions and services
that the industry uses. It promises to provide a flexible IT architecture,
accessible through internet for lightweight portable devices. This would allow
multi-fold increase in the capacity or capabilities of the existing and new
software. In a cloud computing environment, the entire data reside over a set
of networked resources, enabling the data to be accessed through virtual
machines. Since these data-centers may lie in any corner of the world beyond
the reach and control of users, there are multifarious security and privacy
challenges that need to be understood and taken care of. Also, one can never
deny the possibility of a server breakdown that has been witnessed, rather
quite often in the recent times. There are various issues that need to be dealt
with respect to security and privacy in a cloud computing scenario. This
extensive survey paper aims to elaborate and analyze the numerous unresolved
issues threatening the cloud computing adoption and diffusion affecting the
various stake-holders linked to it.
