Re: UDP network problem

Bruce Thompson (bruce@otherother.com)
Sun, 17 Aug 1997 08:55:51 -0700

>> During some experiments with programming UDP/IP sockets, I've noted that I
>> could transfer more than 3250 bytes of data. The sendto() routine says it
>> has sent the data, but recvfrom() just blocks. This is a consistent error.
>
>UDP is an unreliable delivery system, it makes no send/receive guarantees.
>Use TCP if you require these.
>
>Alan

There's also a maximum UDP packet size that you may be running into. Some
implementations of UDP will tell you (return an error) if you try to send a
packet that's too big. Others will silently through the offending packet
away.

It's generally best to send small packets with UDP, typically smaller than
1024 bytes. As Alan says, there's still no guarantee of delivery nor is
there any guarantee of delivery order.

Cheers,
Bruce.

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