Poor man's firewall test

on the Destination host:

nc -l myhost.acme.com 3872

and make sure you are actually listening:

netstat -an | grep 3872
tcp        0      0 10.33.80.121:3872           0.0.0.0:*                   LISTEN

On the Source host:

echo ciao | nc myhost.acme.com 3872

and the "ciao" should appear on Destination and the nc should exit.

If you don't have nc installed, there are alternatives to nc:

wlst or python:

import socket
HOST = 'myhost.acme.com'
PORT = 3872
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

s.connect((HOST, PORT)) 

s.send('Hello, world')
data = s.recv(1024)
s.close()

(see http://docs.python.org/release/2.5.2/lib/socket-example.html)

or simply  run

telnet myhost.acme.com 3872

To receive data, run Java or python:

from java.net import ServerSocket

ss = ServerSocket(3872)

ss.accept()

(see http://docs.oracle.com/javase/6/docs/api/java/net/ServerSocket.html )