All things related to multicast

We are just getting started with multicasting, wondering if anyone can see 
our multicast VBrick streams

MPEG2 at 233.88.214.138, port 4443
MPEG4 at 233.88.214.137, port 4444 for video and 4644 for audio

We are connecting to I2 through the Connecticut Education Network (CEN). Last 
spring we could see our SAPs and streams on CEN, but they were not making it 
to I2 for some reason.

Also, we set up a special subnet just for I2 activities. Just wondering if 
most institutions keep the firewall completely open to all ports for this, or 
whether there is a set of "mutlicast-activity" friendly ports suggested be 
kept open, to specific IPs on the subnet.

Thanks,

Frank Fulchiero
Digital Media Specialist
Connecticut College