[zeromq-dev] Can a pub-sub endpoint have multiple publishers?

[James Renkel]

Randall,

Thank you for your reply.

As I understand your answer, we would have to provide out own daemon.

But that becomes a potential single point of failure, so it would need 
to be replicated.

So, don't we then wind up back at the same place and still have the 
problem that both multiple publishers and multiple subscribers must each 
connect to multiple daemons?

Or am I missing something here?

Jim Renkel
Senior Technical Staff
mFluent, Inc. LLC
mailto:james at mfluent.com

On 14/4/14, 15:05 , Randall Nortman wrote:
> I had the same requirement in my application.  You need a forwarding
> device (either using the official ZMQ device or your own tiny bit of
> code) to make this work.  Yes, you can have multiple PUBs connected to
> a single SUB, but there is no way out of the box to connect multiple
> PUBs to multiple SUBs.  So you have a daemon that binds both a PUB and
> a SUB.  Senders connect a PUB to the daemon's SUB socket, and
> receivers connect a SUB to the daemon's PUB, and the daemon just
> forwards everything from its SUB to its PUB.
>
> Instead of a SUB on the daemon, you can just as easily have a PULL
> socket, and then the senders have a PUSH.  It's really pretty much the
> same thing.  You can even do this with ROUTER/DEALER, but that offers
> no advantages.  You must use a PUB socket on the daemon's send side,
> because there is no other socket type that does fan-out (deliver one
> message to multiple recipients).
>