1. tx.py

      2. rx.py              

                          The example programs given here are just  programmatic realization of things explained in the previous section ( A short Description of VoIP). But these programs are far from reality. And are here only to help those people who are new to this  area of VoIP. Moreover my friends asked me these things, instead of mailing these things to every one, I've thought that this is  a better way of putting things.

                              As it was mentioned already they are far from reality, but surprisingly these little programs work. I've just tested it on a LAN in my college. There is an intolerable delay  as you can see. Because the sampling is done at 1second interval rather than 20ms.  For the reason we have not employed any RTP (Real Time Transport Protocol),no sequence numbers etc etc, it suffers from all the defects which a UDP will be having. That is, packets being lost, arriving out of order etc etc.

                              The two files tx.py & rx.py as the name says it, transmitter & receiver respectively.[ It is customary in electronic communication systems, to use separate frequencies and circuits for transmission & reception to design a full duplex communication link.]  This kind of design is employed to show how things work. If you want to have a full duplex communication, simply run both programs on two end points. & in both windows on your computer enter the IP address of the other person's machine with whom you are communicating. You can also obtain these files in a zip file from the download section of this site.