iperf - A TCP, UDP, and SCTP network bandwidth measurement tool
NetStress - NetStress is a user-friendly benchmarking tool that is mostly used by networking professionals to measure the network performance of both wired and wireless connections.
TamoSoft Throughput Test - TamoSoft Throughput Test is a utility for testing the performance of a wireless or wired network.
Flent - The FLExible Network Tester
nuttcp - nuttcp is another network test tool, similar to iperf2 and iperf3, that has a number of unique features.
NetIO-GUI - NetIO-GUI is a Windows frontend for the multiplatform commandline utility 'netio'.