An efficient date-constraint hierarchical key management scheme for mobile agents

The core competencies of a mobile agent includes its ability to roam freely in different Internet environments, its ability to adapt itself to various types of online servers depending on the characteristics of said server, and its ability to detect its environment and automatic adaptation to said environment while executing the tasks that are assigned by the users. Because of these competencies, the concept of mobile agent is widely used in many different fields, such as Internet business, wireless communication, and information security technologies. Akl and Taylor (1983) suggested the concept of superkey to resolve the key management issues faced by the mobile agent. Later, Volker and Mehrdad (1998) proposed a tree base mobile agent model for access control. The proposed scheme is based upon the studies of public key and a hierarchical mobile agent model with addition of Elliptic Curve Cryptosystem (ECC). ECC enhances the operational ability of mobile agent model, because of shorter key length and higher efficiency on encryption and decryption. In addition, after a period of time, due to error or change in the user’s rights, said user will be forced to log out of the system. At the same time, to prevent a user from continuing to use the old key, the system must keep modifying the key so as to change the original access rights of the key, this action could cause unnecessary error and risks, in addition to the large amount of computations that the system needs to perform. Hence, this paper proposes date-constraint key management scheme, where a date is attached to the key, so as to give a validity period to the key. Thus, key management can be more efficient.