Similar to Netcat

Metasploit

Ping (networking utility)

Tcpdump

Midnight Commander

Common Management Information Protocol

Multi Router Traffic Grapher

Syslog

Syslog-ng

Zabbix

Kismet (software)

Traceroute

Wireshark

Packet analyzer

DCE Distributed File System

Comparison of FTP client software

IFolder

Netstat

Rsync

TCP Wrappers

Unison (software)

WinSCP

GNU Autotools

Banner (Unix)

CUPS

Daemontools