  The Cloud Computing concept offers dynamically scalable resources provisioned
as a service over the Internet.Economic benefits are the main driver for the
Cloud, since it promises the reduction of capital expenditure and operational
expenditure.In order for this to become reality, however, there are still some
challenges to be solved. Amongst these are security and trust issues, since the
user data has to be released to the Cloud and thus leaves the protection sphere
of the data owner. Most of the discussions on these topics are mainly driven by
arguments related to organisational means. This paper focuses on various
security issues arising from the usage of Cloud services and especially by the
rapid development of Cloud computing arena. It also discusses basic security
model followed by various High Level Security threats in the industry.
