## 3 Proposed Framework for Cloud Multi-Factor Multi-Layer Authentication  
As presented in Figure 1, the proposed cloud multi-factor multi-layer authentication framework is based on three main layers with an additional embedded layer for encrypting and decrypting user parameters and authorizations.  
Using IAM is considered a central solution for managing user access to cloud resources. Cloud-based IAM solutions can provide a centralized and scalable way to manage user access, and can support features such as multi-factor authentication and single sign-on. This framework provides a single sign-on (SSO) solution for cloud users, allowing them to authenticate and register for cloud resources using a single identity. The central authority for maintaining user data, producing authentication parameters, and producing identity tokens within the system is a directory provider (DP). The first layer is based on the selection of authentication methods for users based on different priority parameters. The authentication methods are selected based on a priority table that recommends the next appropriate method for user access. By using the priority table, different authentication parameters can be added or modified to the requirements of the organization. The second layer is based on detecting user behavior on the cloud system or platform using different multi-factor authentication parameters. The third layer proposes an algorithm for manipulating the behavior of users based on defined cloud multi-factor authentication methods. The three layers are connected to an additional layer for encrypting user credentials and authentication parameters to prevent any probable disclosure of user information and cloud computing sensitive data.  
Figure 1: Proposed cloud multi-factor authentication framework.  
Multi-factor authentication makes it more difficult for intruders to gain access to the system, even if they have stolen one of the user's authentication factors [85]. This is because the intruder would also need to have access to the user's other authentication factors, such as their geolocation or browser name. By using multiple authentication factors, the framework can help to reduce the number of false alarms. This is because it is less likely that an intruder will be able to provide all of the required authentication factors. The user experience can be also improved provide their authentication factors once, when they first log in to the system. After that, they can access the system without having to provide their authentication factors again. This can save users time and hassle. The rationales for designing the cloud multi-factor multi-layer authentication framework are as follows.  
* To enhance the security of cloud platforms and reduce false alarms.
* To make it more difficult for intruders to gain access to the system, even if they have stolen one of the user's authentication factors.
* To reduce the number of false alarms by using multiple authentication factors.
* To improve the user experience by only requiring users to provide their authentication factors once, when they first log in to the system.  
The framework uses a variety of authentication factors:
* The length, validity, and value of the authentication factor;
* The suspected table;
* The user's geolocation;
* The user's browser name.  
By checking all of these factors, the framework can help to verify that only authorized users can access the cloud system.