Re: UDP network problem
kwrohrer@enteract.com
Tue, 19 Aug 1997 22:48:18 -0500 (CDT)
And lo, Michael Stone saith unto me:
> This recent
> discussion suggesting that the advantage of UDP is that it's a
> non-fragmentable packet whose size is set by a userland program so that
> it fits the smallest MTU between client and host gives me something to
> think about. I guess you really do learn something every day.
Except that it's wrong. UDP is no more unfragmentable than anything
else that runs on top of IP. Packets that don't get fragmented don't
need reassembly, but most TCP implementations do congestion avoidance
and other stuff that some applications just don't need...regardless
of whether the TCP packets need fragmentation... I always saw UDP's
advantages as being connectionless, free of reliability enforcement,
and generally low-overhead; no UNIX system or modern network gateway
would bounce/drop packets rather than refragmenting them appropriately
should they exceed a link's MTU...
Keith