In these days all businesses trying to use global applications on cloud computing infrastructure to reduce their costs and also decentralize their application. This movement also causes more security risks over the unbounded cloud environment. Therefore, accessing enterprise information for an unwanted user will be more than other environments.
Thus, the proposed Identity Management System (IDMS) tries to preserve security in communication between clients and server over cloud computing. The proposed method suggested token based Identity Management and also enhanced privacy by adding one. Dual Certificate Manager (DCM) block is a replacement for a combination of symmetric and asymmetric cryptography, which is commonly used for SSL/TLS protocol to immune data transmission, uses asymmetric cryptography in both participants.
Furthermore, for more privacy and invulnerability DCM uses Elliptic Curve Cryptography (ECC) as asymmetric cryptography algorithm.

These days cloud computing is a main concern for small and medium enterprises. The major concern for these enterprises is about security and privacy. This paper defines privacy and concept of identity management that may help to increase trust in the cloud environment privacy. Cloud computing brings us on-demand service by reduction of hardware costs, but it also suffers from reduction of security. Enterprises scruple to decide which provider is a proper cloud provider by understanding the different types of IDM. IDMs have a major role in applying privacy in various services in cloud computing. Thus, it is vital to have a vision about accessing resources in a secure manner. This paper focused on the SaaS (Software as a Service) and communication on cloud computing environment.