[zeromq-dev] Knowing number of peers in of publisher

[Steven McCoy]

On 4 August 2010 13:09, Bertrand Nouvel <bertrand.nouvel at gmail.com> wrote:

> Hi,
>
> I am quite new with 0MQ. PGM seems really nice.
> I would have one question, I did not find reply in the FAQ/docs.
> Does 0MQ provide a way to know the number of subscriber to a publisher ?
> It would be really convenient in some case to start a broadcast when the
> correct number
> of peers have connected to the publisher.
>
>
At the protocol level, if the peers are functioning bi-directionally like
the TIB it would be possible to find an estimate of the number of receivers.
 However much like RV version 5 versions SASS 3 you really need to implement
subscription logic above PGM, for market data this is usually required for
auditing and entitlements.

At the base level ZeroMQ strictly uses PGM as a uni-directional transport;
the PGM usage does have an upstream for re-transmission requests but is
technically possible to disable it completely and so you would not receive a
single packet from receivers meaning that you must implement the
subscription logic at the higher level.

-- 
Steve-o
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.zeromq.org/pipermail/zeromq-dev/attachments/20100804/db7fc544/attachment.htm>