netcat is a program written by hobbit (hobbit@avian.org) used to create raw udp/tcp connections, etc. .. making it a useful network debugging and exploration utility.

regarding tlf's writeup: Weld Pond, a member of the L0pht, simply ported netcat to NT .. he did not (nor did any member of the L0pht for that matter) originally write the program.

features:

  • Outbound or inbound connections, TCP or UDP, to or from any ports
  • Full DNS forward/reverse checking, with appropriate warnings
  • Ability to use any local source port
  • Ability to use any locally-configured network source address
  • Built-in port-scanning capabilities, with randomizer
  • Built-in loose source-routing capability
  • Can read command line arguments from standard input
  • Slow-send mode, one line every N seconds
  • Hex dump of transmitted and received data
  • Optional ability to let another program service established connections
  • Optional telnet-options responder
list of features retrieved from hobbit's website: http://www.avian.org