Re: Linux Sockets UDP and fragmentation



"toobee84@xxxxxxxxxxxxxx" <toobee84@xxxxxxxxxxxxxx> writes:

ah ok,

TCP handels the fragmentation and UDP don't.

That is not what I wrote! IP fragmentation and re-assembly are
independent of the protocol running on top (TCP and UDP in the two
cases you are comparing). TCP can deal with large transfers for a
whole variety of reasons -- it is complex protocol designed to
implement a reliable end-to-end stream connection. UDP is defined to
be a single IP datagram with a couple of extra header fields. A UDP
packet may be fragmented an re-assembled as it is transmitted across
the net, but this is not related to maximum size of payload.

The usual MTU is install
~1500 Byte but i was wondering why i doesn't work automatic with
bigger packages (till now i used TCP where i didn't have to handel
such things)

If you are used to TCP, make sure you know all of the consequences of
using a simple, unreliable, datagram protocol like UDP before
designing anything important!

--
Ben.
.



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