> > > Syn, ACK and ACK ACK or something. > > > > Let us suppose A and B wants to talk with each other. Then > > Assume you and your brother are at home but in different rooms. You know for sure your brother is at home and is awake and can hear you. In this case, when you want to pass on a message, (eg. switch off the TV) then you can shout out the message and get on with your work.
In case you are not sure your brother is at home or is awake, then if you want to ensure your message reaches your brother you have to ensure he is capable of receiving the message before you can send it. So, you first call out his name (SYN), get an acknowledgement (ACK) fro him and then shout out the message The first case is connectionless (think UDP) and the second case is connection oriented (TCP) IIRC, most implementations of TCP do away with the ACK-ACK part and start sending the message on receipt of ACK because as you can see from above its redundant - you dont necessarily have to ACK ACK your brothers ACK by saying, 'oh, you are there' before you start your transmission :-). regds, mano _______________________________________________ ILUGC Mailing List: http://www.ae.iitm.ac.in/mailman/listinfo/ilugc
