If you send that large UDP packets, something went massively wrong anyway as UDP is only used for low latency - high performance networking. Not for "continous data streams", which is TCPs job.
Not that sure that the network end will split it up ... it could as well just die down as Goldstars problem a few threads below this shows and he was using the TCP Socket, not the UDP one.
You will have to handle all that kind of stuff including handshaking, message reordering, reliability etc which you most likely will need (to drop ordered packets that shall be dropped if a newer one is present and a few other things) yourself. The socket does not give you more than a possibility to talk to someone else through UDP.
But your app has to make sure that the "letters have a valid weight", are sent with "signature needed" etc to tell it in paper mail terms.
Not that sure that the network end will split it up ... it could as well just die down as Goldstars problem a few threads below this shows and he was using the TCP Socket, not the UDP one.
You will have to handle all that kind of stuff including handshaking, message reordering, reliability etc which you most likely will need (to drop ordered packets that shall be dropped if a newer one is present and a few other things) yourself. The socket does not give you more than a possibility to talk to someone else through UDP.
But your app has to make sure that the "letters have a valid weight", are sent with "signature needed" etc to tell it in paper mail terms.