ANT
ANT (Advanced Net Tools) includes a whole suite of network utilities, including ones for conducting ports scans, DNS lookups and pings, and scanning for network shares, checking on routing tables and more. (…)
PuTTY
PuTTY is a terminal emulator application which can act as a client for the SSH, Telnet, rlogin, and raw TCP computing protocols. (…)
Wireshark
Wireshark is a free network packet sniffer computer application. It is used for network troubleshooting, analysis, software and communications protocol development, and education. (…)