Abstract
Cloud Computing is a new technology that allows access to applications as utilities over the Internet. Cloud computing environment provides a great flexibility and availability of computing resources at a lower cost. However, it brings new security concerns mainly when users understand exactly how a process is running. One of the main important challenges in cloud computing is data security, as users need to access data they share securely. So the main problem is how to employ an effective authentication procedure for ensuring data security and preventing unauthorized users to access the authorized user's data. This paper identifies the security issues of single level authentication and the problem of single password. This study proposed a new security mechanism for cloud computing based on multilevel authentication. The proposed scheme aimed to enhance the security and authentication process in cloud computing. The proposed scheme consists of three level of authentication, and the data will be splitting on this level depending on the sensitivity to confidential (C), secret (S), and top secret (TS). Data at level (C) have the lowest sensitivity. The user at this level has single textual password to access this level data. The user at level (S) has two passwords, textual and biometrics password to access this level and the lower level. User at level (TS) has three password textual, biometrics password and image sequencing password. The data at this level is the more sensitive data so it is encrypted using RSA algorithm before storing in cloud database. The results of the proposed multilevel authentication for cloud computing were promising.