During the last years it has become recognized that trust is an essential component in the design of protocols in distributed systems If for example a Key Distribution Center KDC is employed to distribute public keys the receiver of such a key has to trust the KDC that the key is authentic Sometimes a trusted entity may recommend another entity as being trustworthy which in turn can recommend f...

    Discrete facility location,   Distribution center,   Logistics,   Inventory policy,   Queueing theory,   Markov processes, The distribution center location problem is a crucial question for logistics decision makers. The optimization of these decisions needs careful attention to the fixed facility costs, inventory costs, transportation costs and customer responsiveness. In this paper we stu...

We address the problem of content replication in large distributed content delivery networks, composed of a data center assisted by many small servers with limited capabilities and located at the edge of the network. The objective is to optimize the placement of contents on the servers to offload as much as possible the data center. We model the system constituted by the small servers as a loss...

Effective widespread deployment of cryptographic technologies such as secure email and IPsec has been hampered by the difficulties involved in establishing a large scale public key infrastructure, or PKI. Identity-based cryptography (IBC) can be used to ameliorate some of this problem. However, current approaches to using IBC for email or IPsec require a global, trusted key distribution center....

Hierarchical access control to ensure multiple levels of access privilege for group members is required in many environments, such as hierarchically managed organizations and multimedia applications. In this paper, to efficiently and effectively achieve this goal, we propose a distributed key management scheme whereby each SG (Service Group) maintains an SG server. This server is utilized to ma...