I think all you need to do is to write a simple client, using sockets.

UDP was never meant to acknowledge data receipt - so the ack meachnism isn't built in the protocol. If you'e building the ack mechanism on top of UDP, you need to realize that
1. Do you want to send an ack for every packet received? This is quite a big overhead.
2. What if the ack packet is lost? Would you implement a timeout mechanism at the sending end to retransmit the packet if an ack is not received before the timeout?
3. If it is a two-way communication, would you want to implement piggybacking where the ack would be sent alongwith data?

You'd realize that as you address these problems, you're approaching TCP itself

Hope that helps.

Kapil Sharma