[zeromq-dev] zmq fundamental clarification

[Joachim Worringen]

On 01/25/2013 03:10 PM, Steven McCoy wrote:
> On 25 January 2013 04:10, Joachim Worringen <joachim.worringen at iathh.de
> <mailto:joachim.worringen at iathh.de>> wrote:
>
>     2. Does zmq support source-specific multicast?
>
>
> 0mq does not but OpenPGM does.  The limitation is the transport
> specification and how to incorporate the semantics of SSM.
>
> Suggestions welcome, or you could maybe patch in a new 0mq socket option
> to add SSM support: you can add new sources to PGM at any time:
>
>     pgm_setsockopt (sock, IPPROTO_PGM, PGM_JOIN_SOURCE_GROUP,
>     &group_source_req, sizeof (group_source_req)
>
>
> OS limitations may prevent joining a SSM group after a ASM group:
>
>     http://msdn.microsoft.com/en-us/library/windows/desktop/ms739174(v=vs.85).aspx
>
>
> Possible new super-terse syntax:
>
>     pgm://eth0;[ff08::1]@[2a03:2880:10:1f02:face:b00c::25],[ff08::1]@[2a03:2880:10:1f02:face:b00c::26];[ff08::2]

Interesting. Seems to be not to complex to add, yes.

I haven't used pgm yet; I remember the Oracle approach (rdp, IIRC).
How is the recovery implemented? I assume the sender buffers the last N 
datagrams sent, and on request either sends them again if possible or 
signals "datagram not available". Along these lines?

thanks, Joachim