[zeromq-dev] Forwarders and slow network links

[Martin Sustrik]

Hi Phillip,

> We have a situation where we have a cluster of services in one physical
> location, and another cluster of services in another physical location.
> The two physical locations are connected by a relatively slow network
> link. The services in each physical location communicate with each other
> using PUB/SUB and a shared zmq_forwarder.
>
> We want to allow services in different physical locations to communicate
> with each other, but we do not want all network traffic to travel over
> the slow link.
>
> If server-side filtering was functioning, I think that would perfectly
> fulfil our need. But while that is not operational, could anyone give
> some ideas as to how we might solve this problem?

Yes. What's needed is server-side filtering with proper subscription 
forwarding via multiple network hops.

Lot of the work has already been done on sub-forward branch:

https://github.com/zeromq/libzmq/tree/sub-forward

Martin