## 2 Identity Model  
Identity management is used for assuring that individuals receive the appropriate access to resources. It handles the overall methods and regulations that handle the lifecycle of identity traits for a specific domain [7; 18]. Attributes required by authorizing services that describe individuals and use of that data can be diverse. An ethical committee such as IRB can require researcher's personal attributes and a research plan before it can process a request and permit use of sensitive data for a particular research purpose. To choose the right type of system from the point of view of a cloud CDM, we summarize identity models and their systems in research institutes and hospitals. Many of the use cases identified by the research communities call for personal information to be aggregated with community defined attributes in order to grant access to digital resources and services. Compared with existing use cases, this aggregation means that an external attribute authority that is typically managed by the research community itself is needed in addition to the IdP and SP. Based on the level of authorization within the different services depends on the credentials presented by the user in the cloud CDM. FIM has a limitation to support assurance and enforcement in terms of the level of security within systems and across boundaries from one to another. In a centralized or federated identity model, users create accounts to access systems and authenticate transactions with many different identity providers. Organizations collect and store personal and sensitive information about their users to enable services. This results in our digital identities being spread all over the web, making ID theft, credential compromise, and breaches a real possibility with potentially significant long-term impacts for both individuals and businesses. However, it is not easy to protect the problem caused by security breaches resulting in unauthorized access to personal data in the organization. The distributed ID type is operated in such a way that users create their own identification information and share it through DLT. The convenience of identity management can be improved as the procedure for registering verification information becomes unnecessary. In terms of the safety of the security system, the user's identity is not stored in the central server, so there is little risk of security leakage or theft, and it has the advantage of ensuring the integrity of the identification information. Self-sovereign identity refers to a blockchain-based distributed self-sovereign identity management technology that allows users to directly manage their identity and to select the subject and the scope of disclosure. Distributed ID is used as a technique for this. Self-sovereign identity systems are decentralized and operate in the same way as real-life identities because they do not depend on a central authority. The user has all the rights such as issuance, submission, deletion, and recovery of the identity certificate, and the blockchain proves that the identity certificate is owned by the user and is used for record management such as issuance, submission, and renewal of the identity certificate. The baseline of identity management architecture is shown in Figure 1. It is made up of the user or object, a service provider (SP), and an identity provider (IdP). Identity management systems are used by the SPs to authorize users and to give them access to the services. * A subject must submit a request for an identity from the identity manager in order to access the desired service. Based on the data the subject has provided, the identity manager then creates a distinct identity and responds to the subject. * The subject demands a certain service from the service provider, who then asks the subject for identification details. The request is received by the subject, who then responds with the pertinent information. * The service provider asks the identity provider to confirm that the user's identification is legitimate.