I found the multicast registery here.
https://www.iana.org/assignments/multicast-addresses/multicast-addresses.xhtml
I already knew that addresses between 224.0.0.1 and 239.255.255.255 are reserved by multicast.
Obviously multicast could be immensely useful if used by the general public, it would obsolete much of facebook, youtube, nearly all CDNs (content delivery networks), would kill cloudflare and company’s business model and just re-arrange the internet with far reaching social implication.
So, why hasn’t all these multicast addresses been converted in usable private IPv4 unicast address space ?
I’m explaining what the technical problems are with your idea. It seems like you don’t fully understand the technical details of these networking protocols and that’s okay but I’ve summarized a few non trivial technical problems that aren’t just people keeping multicast from being used. I assure you if multicast worked, big tech would want to use it. For example, Netflix would want to use it to distribute content to their CDN boxes and save tons of bandwidth.
But it does work if you run it on a parallel network, if you side step all the ISP’s toll bridges.
What you can’t do is negotiate with every ISP on the internet between you and your end users, giving a 30% cut to every one of them along the way. Especially since most of these ISPs were cable TV distributors in their previous life. They made sure to break it, to break it so good it becomes unimaginable that it could ever have worked in the first place.
And I think that has turned out just fine for netflix, the enormous deployment costs for their CDN means they have a moat, no small operator is going to be eating their lunch. Add to that brand name and platform power, the lack of standardized “one-to-many” infrastructureless broadcasting method, like “email” for broadcasting.
We’ll be stuck using Zuck’s computer to talk to each other pretty much forever now …