[ENet-discuss] Large data packets over ENet

[Chris Dellario]

> I know what you mean, but I tried TCP, and it doesn't work for me. The
problem is the latency: Ideally, I want to connect 16 or more computers.
This would allow me to render 1024x768 @ 25fps or faster. The size of
the transfer would indeed justify TCP, but the desired speed makes this
a less optimal choice. I heard that there's a protocol for streaming
video; that might be something to check out. In my case, it's not a big
problem when I miss a packet; it would mean that some display lines
don't get updated for one frame. But speed is essential.

Forgive me if I'm misunderstanding the issue, but the problem seems to
stem from your use of large packets.  The average MTU is under 1500
bytes and around 576 for dialup, and anything over that is going to
cause fragmentation of the packets which will kill you.  Remember that
if a packet gets fragmented under UDP then the entire datagram will be
tossed if even one of the fragments doesn't make it.  If you're trying
to stream video than UDP should give you better overall performance than
TCP, as you need speed and don't care about packet loss, but the size of
the packets needs to fall below your MTU.


Chris Dellario
Lead Engineer
Whatif Productions LLC
http://www.whatif.info
(617) 977-0115