MCastTest is a utility for testing IP multicast routing on your network. You can add multiple tranmitters and listeners on different IP multicast groups. By running this utility on multiple machines at different points in your network you can check that your multicast traffic is getting to where it is supposed to get to.
I started to write this utility several years ago but never finished it. It isn't even close to being finished. Lots of the controls on it are statements of intent at the moment (!). However the venerable "mcaster" utility that many network engineers used to use for multicast testing (it was even recommended by Cisco) appears to have vanished off the face of the earth and there is enough funtionality in my version - even in its current, unfinished form - to make it useful as a replacement.
The usual disclaimers apply: provided without warranty of any kind, use at your own risk etc. etc.