On large Computational Grids, performance is one of the main problems that has to be addressed but another important issue is the underlying interconnection network that has to be reliable in order to ensure the nodes’ intercommunication and the migration of the appropriate load from one node to others. Reliability and performance are both influenced by the topology type of the underlying network. Fully connected networks for example provide better performance, the number of links however increases the cost of the system. In this paper, we considered these three factors, namely performance, reliability and cost, simulating performance for different network topologies and different reliability thresholds. The simulation results demonstrate that 1) regular topologies behave better than irregular topologies, and 2) the topology of the network is more influential to performance than the actual number of physical links.