A node functions as the server for the data on the disk or disks that the node
owns. Since local disk references are serviced by local disks at each processor,
the shared-nothing model overcomes the disadvantage of requiring all I/O to go
through a single interconnection network; only queries, accesses to nonlocal disks,
and result relations pass through the network. Moreover, the interconnection
networks for shared-nothing systems are usually designed to be scalable, so that
their transmission capacity increases as more nodes are added