The OPTGRAPH procedure in SAS High-Performance Network Algorithms enables you to perform community detection and centrality computations on large graphs in a high-performance environment. It uses an appliance that houses a massively parallel database management system (Teradata or EMC Greenplum) to manage data in distributed form and to perform computations in parallel on an x64 Linux platform. A computing appliance is a dedicated hardware and software environment that acts as a server to provide computing resources in a client/server model. You connect indirectly to the appliance through the network connection between the client machine and the appliance. Software instructions on the client machine are translated into commands that are run on the appliance. For information about installing SAS High-Performance Network Algorithms, see the SAS High-Performance Analytics Infrastructure: Installation and Configuration Guide. PROC OPTGRAPH runs in either single-machine mode or distributed mode. Note: Distributed mode requires SAS High-Performance OPTGRAPH.