Secure referee selection for fair and responsive peer-to-peer gaming

Peer-to-Peer (P2P) architectures for Massively Multiplayer Online Games (MMOG) provide better scalability than Client/Server (C/S); however, they increase the possibility of cheating. Recently proposed P2P protocols use trusted referees that simulate/validate the game to provide security equivalent to C/S. When selecting referees from untrusted peers, selecting non-colluding referees becomes critical. Further, referees should be selected such that the range and length of delays to players is minimised (maximising game fairness and responsiveness). In this paper we formally define the referee selection problem and propose two secure referee selection algorithms, SRS-1 and SRS-2, to solve it. Both algorithms ensure the probability of corrupt referees controlling a zone/region is below a predefined limit, while attempting to maximise responsiveness and fairness. The trade-off between responsiveness and fairness is adjustable for both algorithms. Simulations of three different scenarios show the effectiveness of our algorithms

Received Revised

Communicated by Dynamically reconfigurable architectures offer extremely fast solutions to various problems. The Circuit Switched Tree (CST) is an important interconnect used to implement such architectures. A CST has a binary tree structure with processing elements (PEs) as leaves and switches as internal nodes. PEs communicate among themselves using the links of the tree. Key components for successful communication are scheduling individual communications and configuring the CST switches. This paper presents a scheduling and configuration algorithm for communications on a CST where conflicts necessitate multiple rounds of routing to perform all communications. The algorithm is distributed and requires only local information, yet it captures the global picture to ensure proper communication. The paper also explains how to apply the algorithm to an important class, “well-nested communications”, for which the algorithm is optimal and efficient

Fault tolerant algorithms for a linear array with a reconfigurable pipelined bus system

Recently, many models using recon gurable optically pipelined buses have been proposed in the literature. All algorithms developed for these models assume that a healthy system is available. We present some fundamental algorithms that are able to tolerate up to N/2 faults on an N-processor LARPBS (one particular optical model). We then extend these results to apply to other algorithms in the areas of image processing and matrix operations