Re: UDP packets dropping


"Guddu" <vishal21@xxxxxxxxx> wrote in message
news:1163164373.286060.51090@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi,
I am facing a problem which anyone who has worked on any UDP
application might have faced.
UDP by itself is unreliable. If packets are lost, no acknowledgements
are sent.

I think your answer is right there in the second sentence. Since UDP is
best-effort you can never be sure whether you've lost a packet unless the
higher level protocol does some kind of checking. Monitoring the receiving
socket state may help but packets could be lost for other reasons so if your
upper protocol depends on reliable delivery you have to implement that with
sequence numbers, acknowledgements or whatever mechanism is best suited to
your app.

This will become very obvious if you move to wireless or some other
transport that's less reliable than Ethernet.

Hope that helps,
Andrew


.

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