On Mon, Aug 16, 2010 at 9:29 PM, Matt Weinstein <matt_weinstein at yahoo.com> wrote: > Doesn't IP MCAST change this to P(M x Z) x F ? > F = burden for reliable pub/sub, perhaps 1.1 or so. Yes, with multicast a message is sent exactly once no matter how many subscribers receive it. - Pieter Hintjens iMatix - www.imatix.com