ZeroMQ PUB/SUB filtering and performance
From the ØMQ guide:

From ZeroMQ v3.x, filtering happens at the publisher side when using a connected protocol (tcp:// or ipc://). Using the epgm:// protocol, filtering happens at the subscriber side. In ZeroMQ v2.x, all filtering happened at the subscriber side.
I am trying to implement a broker using zeromq PUB/SUB(python eventlets). zeromq 2.1 does not seem to implement filtering at publisher and all messages are broadcasted to all subscribers which inturn apply filter. Is there some kind of workaround to achieve filtering at publisher. If not how bad is the performance if there are ~25 publishers and 25 subscribers exchanging msgs @ max rate of 200 msgs per second where msg_size ~= 5K through the broker. 
Are there any opensource well-tested zero-mq broker implementations.??