Using Iperf version 2.0.9 on Debian (Stretch) it’s possible to test networks using a multicast connection.
On the receiving end execute the command:
iperf -s -u -B 126.96.36.199 -i 1
On the sending end execute the command:
iperf -c 188.8.131.52 -u -T 3 -t 10 -i 1 -b 100M
This will run a bandwidth test using UDP traffic at 100Mbps.
Note, if your system is multi-homed you must make sure your multicast traffic is routed out of the correct interface. For example:
ip route add 184.108.40.206/4 dev eth0