I'm testing multicast imaging with ZENworks Configuration Management 10.1. The environment consists of the imaging server on a 1 Gb/s link and the PCs are on 100 Mb/s links. I have found during testing of multicast imaging that it is much slower than unicast imaging. However, when moving the server to a 100 Mb/s link, the time it takes to image PCs via multicast imaging returns to an acceptable time.

I sniffed the data stream between the imaging server and the PCs. I have found that during multicast imaging, there is half second delay in the UDP stream every 5-15 minutes. My theory is that if the server is on a 1 Gb/s link to the switch and the PCs are on 100 Mb/s link, then the server is stopping to allow the PCs to catch up.

Can someone provide insight into this? Is this by design or an issue?