iperf - A TCP, UDP, and SCTP network bandwidth measurement tool
MobaXterm - MobaXterm is a software that uses a set of optimized network tools included in a single exe file. MobaXterm integrates several network clients with an X server, and also integrates a full set of Unix based commands. Read more about MobaXterm.
PingPlotter - PingPlotter is a troubleshooting tool that helps IT professionals and neophytes identify, diagnose, and resolve network issues.
PuTTY - Popular free terminal application. Mostly used as an SSH client.
SmokePing - Smokeping is a tool for measuring latency.
Terminator - Terminator is one of the most useful and dynamic terminal emulators for Unix based operating systems.