It's a network performance benchmark server. Listens for connections from a benchmark, and responds accordingly. It can either be run from or as a standalone daemon (with the -p flag). If run from, the -p option should not be used.
Usage: netserver [options] Options: -h : Display this text -d : Increase debugging output -L name,family : Use name to pick listen address and family for family -p portnum : Listen for connect requests on portnum. -4 : Do IPv4 -6 : Do IPv6 -v verbosity : Specify the verbosity level -V : Display version information and exit