What is the simple Linux utility that is like cat but works via TCP (to be used for port knocking)?

Question

For port knocking over at my old job, one of the SAs use to perform something like the following:

 echo 'blah' > tcpcat -a 192.168.3.1 -p 2222 && ssh beamin@192.168.3.1

I cannot remember the command that I am referring to as tcpcat. Does anyone know?

Answer 1

ncat may be the tool you're looking for.

Answer 2

It may be called netcat, Lowercase nc is what the command actually is.