UDP multicast is widely used by financial trading networks to distribute state-of-the-market updates. Getting those networks to work reliably (ie. right groups

UDP multicast is widely used by financial trading networks to distribute state-of-the-market updates. Getting those networks to work reliably (ie. right groups distributed to right places with minimal packet loss, reordering, latency and jitter) is orders of magnitude more difficult than getting unicast traffic working. I don't think it's going to happen. Our current networks can't even do unicast well (eg. bufferbloat, general ISP randomness). But I'd be keen to read the OP's rants if someone tried ...