[zeromq-dev] Unreliable multicast was: udp not enabled on Mac OS X 10.6

[Martin Sustrik]

Chris Wong wrote:
> Actually i want support for unreliable multicast vs reliable multicast.  
> Zeromq is a nice framework to allow me to transparently switch the 
> underlying transport. There are applications that don't need the 
> ordering and lossless guarantee of PGM.
> 
> The unreliable multicast transport may or may not work for all the 
> messaging pattern but should at least work for the multicast pattern.

Now it makes sense. Paradoxically, unreliable multicast is easier to 
implement than unreliable unicast.

Just copy pgm_sender.cpp/.hpp and pgm_receiver.cpp/.hpp, name it 
udp_sender/udp_reciever. Rip off OpenPGM stuff, use UDP socket instead.

One additional thing that has to be done is to attach a sequence number 
to each UDP packet, so that you know when packet was lost.

Martin