Making a TCP or UDP or Unux Socket Server Listen on a port

[<shyamk@eth.net>]

I am having  Server Programs (for TCP,UDP,Unix Sockets) , that listen on a port
number say , 9888 at
10.10.1.4
and they are being contacted by a Client (for TCP,UDP,Unix Sockets)  Linux machine
from 10.10.1.1 .

Both macines are on the LAN , nothing more nothing less . We have not yet gone for
any higher stuff like DNS , etc . So , basically  10.10.1.4
and 10.10.1.1 are not on any Linux network , but simply they identify and respond on
the LAN.

My Clients and Server (socket  programs) do not communicate at all on this network .

Please guide me on what I should do .

My line of thinking is : Add some  entry to the
/etc/services   specifying the port , but this is what I tried and failed :-
# At the bottom of /etc/services  :-
tcp 9888/tcp
a.out 9889/tcp

Please help me get these programs to communicate .

Warm regards,
(shyamk@eth.net)
Shyam