Sysmon is a network monitoring tool designed to provide high
performance and accurate network monitoring.

This tool is available in the public domain for anyone to use
it that is interested. It provides better performance and
checking capabilities than other tools such as Rover, Nocmon
(not this: Nocmonitor),Whatsup, Big Brother, and other such tools.

Currently supported protocols include SMTP, IMAP, HTTP,TCP,
UDP, NNTP, and PING tests.

WWW: http://puck.nether.net/sysmon/